Answer: 700 nm

Context: The onset of infrared is defined (according to different standards) at various values typically between 700 nm and 800 nm, but the boundary between visible and infrared light is not precisely defined. The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources. However, particularly intense near-IR light (e.g., from IR lasers, IR LED sources, or from bright daylight with the visible light removed by colored gels) can be detected up to approximately 780 nm, and will be perceived as red light. Sources providing wavelengths as long as 1050 nm can be seen as a dull red glow in intense sources, causing some difficulty in near-IR illumination of scenes in the dark (usually this practical problem is solved by indirect illumination). Leaves are particularly bright in the near IR, and if all visible light leaks from around an IR-filter are blocked, and the eye is given a moment to adjust to the extremely dim image coming through a visually opaque IR-passing photographic filter, it is possible to see the Wood effect that consists of IR-glowing foliage.

Question: At what wavelength does the human eye become significantly less sensitive to light?


Answer: near-IR

Question: What sort of light is generated by IR lasers?


Answer: 780 nm

Question: Up to what wavelength does the human eye perceive IR LED sources as red?


Answer: 1050 nm

Question: Up to what wavelength does the human eye perceive certain intense lights as being dull red in color?


Answer: Leaves

Question: What objects are notably bright in near IR?


Answer: emissivity

Context: The concept of emissivity is important in understanding the infrared emissions of objects. This is a property of a surface that describes how its thermal emissions deviate from the ideal of a black body. To further explain, two objects at the same physical temperature will not show the same infrared image if they have differing emissivity. For example, for any pre-set emissivity value, objects with higher emissivity will appear hotter, and those with a lower emissivity will appear cooler. For that reason, incorrect selection of emissivity will give inaccurate results when using infrared cameras and pyrometers.

Question: What is the term for the property that describes how a surface's thermal emissions deviate from the ideal of a black body?


Answer: hotter

Question: How will the infrared image of an object with a higher emissivity appear in relation to one with lower emissivity?


Answer: infrared cameras

Question: Along with pyrometers, what devices can receive inaccurate results if emissivity is not set correctly?


Answer: Infrared vibrational spectroscopy

Context: Infrared vibrational spectroscopy (see also near-infrared spectroscopy) is a technique that can be used to identify molecules by analysis of their constituent bonds. Each chemical bond in a molecule vibrates at a frequency characteristic of that bond. A group of atoms in a molecule (e.g., CH2) may have multiple modes of oscillation caused by the stretching and bending motions of the group as a whole. If an oscillation leads to a change in dipole in the molecule then it will absorb a photon that has the same frequency. The vibrational frequencies of most molecules correspond to the frequencies of infrared light. Typically, the technique is used to study organic compounds using light radiation from 4000–400 cm−1, the mid-infrared. A spectrum of all the frequencies of absorption in a sample is recorded. This can be used to gain information about the sample composition in terms of chemical groups present and also its purity (for example, a wet sample will show a broad O-H absorption around 3200 cm−1).

Question: What is the technique that analyzes the constituent bonds of molecules to identify them?


Answer: it will absorb a photon that has the same frequency

Question: What happens to a molecule if an oscillation results in a dipole being changed?


Answer: the frequencies of infrared light

Question: What do the vibrational frequencies of molecules usually correspond to?


Answer: the mid-infrared

Question: What is the term for light radiation in the 4000–400 cm−1 spectrum?


Answer: infrared filters

Context: In infrared photography, infrared filters are used to capture the near-infrared spectrum. Digital cameras often use infrared blockers. Cheaper digital cameras and camera phones have less effective filters and can "see" intense near-infrared, appearing as a bright purple-white color. This is especially pronounced when taking pictures of subjects near IR-bright areas (such as near a lamp), where the resulting infrared interference can wash out the image. There is also a technique called 'T-ray' imaging, which is imaging using far-infrared or terahertz radiation. Lack of bright sources can make terahertz photography more challenging than most other infrared imaging techniques. Recently T-ray imaging has been of considerable interest due to a number of new developments such as terahertz time-domain spectroscopy.

Question: What is used in infrared photography to capture the near-infrared spectrum?


Answer: Digital cameras

Question: What devices are often equipped with infrared blockers?


Answer: 'T-ray' imaging

Question: What is the technique that involves imaging with terahertz radiation?


Answer: far-infrared

Question: What is another name for terahertz radiation?


Answer: terahertz time-domain spectroscopy

Question: What is a notable recent development in T-ray imaging?


Answer: Infrared reflectography

Context: Infrared reflectography (fr; it; es), as called by art conservators, can be applied to paintings to reveal underlying layers in a completely non-destructive manner, in particular the underdrawing or outline drawn by the artist as a guide. This often reveals the artist's use of carbon black, which shows up well in reflectograms, as long as it has not also been used in the ground underlying the whole painting. Art conservators are looking to see whether the visible layers of paint differ from the underdrawing or layers in between – such alterations are called pentimenti when made by the original artist. This is very useful information in deciding whether a painting is the prime version by the original artist or a copy, and whether it has been altered by over-enthusiastic restoration work. In general, the more pentimenti the more likely a painting is to be the prime version. It also gives useful insights into working practices.

Question: What technique is used in art to examine underlying layers of a painting without damaging it?


Answer: carbon black

Question: What shows up particularly well in reflectograms?


Answer: pentimenti

Question: What is the term for differences in the painting and underdrawing made by the original artist?


Answer: William Herschel

Context: The discovery of infrared radiation is ascribed to William Herschel, the astronomer, in the early 19th century. Herschel published his results in 1800 before the Royal Society of London. Herschel used a prism to refract light from the sun and detected the infrared, beyond the red part of the spectrum, through an increase in the temperature recorded on a thermometer. He was surprised at the result and called them "Calorific Rays". The term 'Infrared' did not appear until late in the 19th century.

Question: Who discovered infrared radiation?


Answer: the Royal Society of London

Question: To whom did Herschel present his work on infrared radiation?


Answer: 1800

Question: In what year did Herschel publish his work on infrared radiation?


Answer: a prism

Question: What device did Herschel use to discover the infrared?


Answer: Calorific Rays

Question: What did Herschel call the infrared spectrum?


Answer: heat radiation

Context: Infrared radiation is popularly known as "heat radiation"[citation needed], but light and electromagnetic waves of any frequency will heat surfaces that absorb them. Infrared light from the Sun accounts for 49% of the heating of Earth, with the rest being caused by visible light that is absorbed then re-radiated at longer wavelengths. Visible light or ultraviolet-emitting lasers can char paper and incandescently hot objects emit visible radiation. Objects at room temperature will emit radiation concentrated mostly in the 8 to 25 µm band, but this is not distinct from the emission of visible light by incandescent objects and ultraviolet by even hotter objects (see black body and Wien's displacement law).

Question: What is a commonly used term for infrared radiation?


Answer: 49%

Question: What percentage of the Earth's heat is derived from the Sun's infrared light?


Answer: 8 to 25

Question: What is the common range of emitted radiation of room temperature objects, in micrometers?


Answer: visible

Question: Other than infrared light, what type of light is responsible for heating the Earth?


Answer: Infrared tracking

Context: Infrared tracking, also known as infrared homing, refers to a passive missile guidance system, which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track it. Missiles that use infrared seeking are often referred to as "heat-seekers", since infrared (IR) is just below the visible spectrum of light in frequency and is radiated strongly by hot bodies. Many objects such as people, vehicle engines, and aircraft generate and retain heat, and as such, are especially visible in the infrared wavelengths of light compared to objects in the background.

Question: What is another term for infrared homing?


Answer: Missiles

Question: What devices make use of infrared homing?


Answer: heat-seekers

Question: What is a common name for missiles that make use of infrared seeking?


Answer: vehicle engines

Question: Along with aircraft and people, what objects notably create and retain heat?


Answer: infrared

Question: What does IR stand for?


Answer: Cumulonimbus

Context: High, cold ice clouds such as Cirrus or Cumulonimbus show up bright white, lower warmer clouds such as Stratus or Stratocumulus show up as grey with intermediate clouds shaded accordingly. Hot land surfaces will show up as dark-grey or black. One disadvantage of infrared imagery is that low cloud such as stratus or fog can be a similar temperature to the surrounding land or sea surface and does not show up. However, using the difference in brightness of the IR4 channel (10.3–11.5 µm) and the near-infrared channel (1.58–1.64 µm), low cloud can be distinguished, producing a fog satellite picture. The main advantage of infrared is that images can be produced at night, allowing a continuous sequence of weather to be studied.

Question: Along with Cirrus, what types of clouds are cold and high?


Answer: white

Question: What color do Cirrus clouds appear in infrared?


Answer: Stratocumulus

Question: Along with Stratus, what clouds are lower and warmer?


Answer: grey

Question: What color are Strarus clouds in infrared?


Answer: 1.58–1.64

Question: What is the range of the near-infrared channel in micrometers?


Answer: water vapor in the atmosphere

Context: The sensitivity of Earth-based infrared telescopes is significantly limited by water vapor in the atmosphere, which absorbs a portion of the infrared radiation arriving from space outside of selected atmospheric windows. This limitation can be partially alleviated by placing the telescope observatory at a high altitude, or by carrying the telescope aloft with a balloon or an aircraft. Space telescopes do not suffer from this handicap, and so outer space is considered the ideal location for infrared astronomy.

Question: What limits the sensitivity of infrared telescopes on Earth?


Answer: at a high altitude

Question: To somewhat avoid the water vapor in the atmosphere, where can an observatory be sited?


Answer: balloon

Question: Along with aircraft, what object can be used to carry a telescope aloft?


Answer: Space telescopes

Question: What sorts of telescopes completely avoid water vapor in Earth's atmosphere?


Answer: Near-infrared

Context: Near-infrared is the region closest in wavelength to the radiation detectable by the human eye, mid- and far-infrared are progressively further from the visible spectrum. Other definitions follow different physical mechanisms (emission peaks, vs. bands, water absorption) and the newest follow technical reasons (the common silicon detectors are sensitive to about 1,050 nm, while InGaAs's sensitivity starts around 950 nm and ends between 1,700 and 2,600 nm, depending on the specific configuration). Unfortunately, international standards for these specifications are not currently available.

Question: What is the nearest wavelength to the radiation that a human eye can see?


Answer: water absorption

Question: Along with the emission peaks and vs. bands mechanisms, what other physical mechanism is used to define near-infrared?


Answer: 1,050

Question: In micrometers, when do common silicon detectors cease to be sensitive?


Answer: 950

Question: What is the lowest level of sensitivity, in micrometers, for InGaAs?


Answer: Heat

Context: Heat is energy in transit that flows due to temperature difference. Unlike heat transmitted by thermal conduction or thermal convection, thermal radiation can propagate through a vacuum. Thermal radiation is characterized by a particular spectrum of many wavelengths that is associated with emission from an object, due to the vibration of its molecules at a given temperature. Thermal radiation can be emitted from objects at any wavelength, and at very high temperatures such radiations are associated with spectra far above the infrared, extending into visible, ultraviolet, and even X-ray regions (i.e., the solar corona). Thus, the popular association of infrared radiation with thermal radiation is only a coincidence based on typical (comparatively low) temperatures often found near the surface of planet Earth.

Question: What is the term for transit energy flowing as a result of differences in temperature?


Answer: thermal radiation

Question: What type of heat transmission can propagate through a vacuum?


Answer: the solar corona

Question: What object emits thermal radiation in the X-ray spectrum?


Answer: infrared

Question: The visible, ultraviolet and X-ray spectra are all above what spectrum?


Answer: 0.9–14

Context: Thermographic cameras detect radiation in the infrared range of the electromagnetic spectrum (roughly 900–14,000 nanometers or 0.9–14 μm) and produce images of that radiation. Since infrared radiation is emitted by all objects based on their temperatures, according to the black body radiation law, thermography makes it possible to "see" one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature, therefore thermography allows one to see variations in temperature (hence the name).

Question: What is the range of the electromagnetic spectrum in micrometers?


Answer: 900–14,000

Question: In nanometers, what is the electromagnetic spectrum's range?


Answer: the black body radiation law

Question: What law states that infrared radiation is emitted by objects based on temperature?


Answer: increases

Question: What happens to the amount of radiation an object emits as temperature increases?


Answer: Thermographic

Question: What type of cameras see infrared radiation?


Answer: imbedded stars

Context: The infrared portion of the spectrum has several useful benefits for astronomers. Cold, dark molecular clouds of gas and dust in our galaxy will glow with radiated heat as they are irradiated by imbedded stars. Infrared can also be used to detect protostars before they begin to emit visible light. Stars emit a smaller portion of their energy in the infrared spectrum, so nearby cool objects such as planets can be more readily detected. (In the visible light spectrum, the glare from the star will drown out the reflected light from a planet.)

Question: What irradiates clouds of gas in the galaxy and makes them glow?


Answer: protostars

Question: What can be detected via infrared prior to their emitting visible light?


Answer: Stars

Question: What objects emit less of their energy as infrared light versus visible light?


Answer: night vision

Context: Infrared is used in night vision equipment when there is insufficient visible light to see. Night vision devices operate through a process involving the conversion of ambient light photons into electrons that are then amplified by a chemical and electrical process and then converted back into visible light. Infrared light sources can be used to augment the available ambient light for conversion by night vision devices, increasing in-the-dark visibility without actually using a visible light source.

Question: What sort of equipment uses the infrared spectrum in the absence of sufficient visible light?


Answer: electrons

Question: What do night vision devices convert ambient light photons into?


Answer: electrical

Question: Along with a chemical process, what type of process is used by night vision devices to convert infrared into visible light?


Answer: the Infrared Data Association

Context: IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants. These devices usually conform to standards published by IrDA, the Infrared Data Association. Remote controls and IrDA devices use infrared light-emitting diodes (LEDs) to emit infrared radiation that is focused by a plastic lens into a narrow beam. The beam is modulated, i.e. switched on and off, to encode the data. The receiver uses a silicon photodiode to convert the infrared radiation to an electric current. It responds only to the rapidly pulsing signal created by the transmitter, and filters out slowly changing infrared radiation from ambient light. Infrared communications are useful for indoor use in areas of high population density. IR does not penetrate walls and so does not interfere with other devices in adjoining rooms. Infrared is the most common way for remote controls to command appliances. Infrared remote control protocols like RC-5, SIRC, are used to communicate with infrared.

Question: What is the IrDA?


Answer: light-emitting diodes

Question: What does the acronym LEDs stand for?


Answer: modulated

Question: What is a term for when something is switched on and off?


Answer: silicon photodiode

Question: What device is used to transform infrared radiation into an electric current?


Answer: IR does not penetrate walls

Question: Why does infrared not cause trouble for devices in adjacent rooms?


Answer: n

Context: In the semiconductor industry, infrared light can be used to characterize materials such as thin films and periodic trench structures. By measuring the reflectance of light from the surface of a semiconductor wafer, the index of refraction (n) and the extinction Coefficient (k) can be determined via the Forouhi-Bloomer dispersion equations. The reflectance from the infrared light can also be used to determine the critical dimension, depth, and sidewall angle of high aspect ratio trench structures.

Question: What letter represents the index of refraction?


Answer: k

Question: What letter represents the extinction Coefficient?


Answer: Forouhi-Bloomer dispersion

Question: What equations are used to figure out the index of refraction and extinction Coefficient?


Answer: sidewall angle

Question: Along with critical dimension and depth, what can the infrared light reflectance be used to determine in regard to high aspect ratio trench structures?


Answer: light

Question: What reflectance is measured from a semiconductor wafer's surface to determine the index of refraction?


Answer: Infrared cleaning

Context: Infrared cleaning is a technique used by some Motion picture film scanner, film scanners and flatbed scanners to reduce or remove the effect of dust and scratches upon the finished scan. It works by collecting an additional infrared channel from the scan at the same position and resolution as the three visible color channels (red, green, and blue). The infrared channel, in combination with the other channels, is used to detect the location of scratches and dust. Once located, those defects can be corrected by scaling or replaced by inpainting.

Question: What is the name of the technique used in scanners to minimize the effects of dust and scratches?


Answer: green

Question: Along with red and blue, what is the third visible color channel?


Answer: scaling

Question: Along with replacement via inpainting, what procedure is used in infrared cleaning to remove the effect of scratches and dust?


Answer: infrared

Question: Along with the visible light channels, what channel is used to locate scratches and dust in scanners?


Answer: clouds

Context: Earth's surface and the clouds absorb visible and invisible radiation from the sun and re-emit much of the energy as infrared back to atmosphere. Certain substances in the atmosphere, chiefly cloud droplets and water vapor, but also carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, and chlorofluorocarbons, absorb this infrared, and re-radiate it in all directions including back to Earth. Thus, the greenhouse effect keeps the atmosphere and surface much warmer than if the infrared absorbers were absent from the atmosphere.

Question: Along with the surface of the Earth, what objects absorb radiation from the sun?


Answer: infrared

Question: After Earth surface's absorbs radiation, in what spectrum is much of it re-emitted?


Answer: cloud droplets

Question: Along with water vapor, what atmospheric substance primarily absorbs the infrared emitted by the Earth?


Answer: greenhouse

Question: What notable warming effect does the presence of infrared absorbers contribute to?


Answer: Biodiversity

Context: Biodiversity, a contraction of "biological diversity," generally refers to the variety and variability of life on Earth. One of the most widely used definitions defines it in terms of the variability within species, between species, and between ecosystems. It is a measure of the variety of organisms present in different ecosystems. This can refer to genetic variation, ecosystem variation, or species variation (number of species) within an area, biome, or planet. Terrestrial biodiversity tends to be greater near the equator, which seems to be the result of the warm climate and high primary productivity. Biodiversity is not distributed evenly on Earth. It is richest in the tropics. Marine biodiversity tends to be highest along coasts in the Western Pacific, where sea surface temperature is highest and in the mid-latitudinal band in all oceans. There are latitudinal gradients in species diversity. Biodiversity generally tends to cluster in hotspots, and has been increasing through time, but will be likely to slow in the future.

Question: What term refers to the variety and variability of life on Earth?


Answer: genetic variation, ecosystem variation, or species variation

Question: What types of variations does Biodiversity refer to?


Answer: Terrestrial biodiversity

Question: What type of biodiversity happens near the equator?


Answer: It is richest in the tropics.

Question: Where on Earth is biodiversity the most abundnant?


Answer: along coasts in the Western Pacific

Question: Where is sea surface temperature the highest?


Answer: Bruce A. Wilcox

Context: This multilevel construct is consistent with Dasmann and Lovejoy. An explicit definition consistent with this interpretation was first given in a paper by Bruce A. Wilcox commissioned by the International Union for the Conservation of Nature and Natural Resources (IUCN) for the 1982 World National Parks Conference. Wilcox's definition was "Biological diversity is the variety of life forms...at all levels of biological systems (i.e., molecular, organismic, population, species and ecosystem)...". The 1992 United Nations Earth Summit defined "biological diversity" as "the variability among living organisms from all sources, including, 'inter alia', terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems". This definition is used in the United Nations Convention on Biological Diversity.

Question: Who is the author of the biodiversity research paper?


Answer: International Union for the Conservation of Nature and Natural Resources (IUCN)

Question: Who commissioned the biodiversity research paper?


Answer: 1982 World National Parks Conference

Question: At what event was the biodiversity research paper presented?


Answer: 1992

Question: What year did the United Nations Earth Summit define "biological diversity"?


Answer: the Phanerozoic

Context: On the other hand, changes through the Phanerozoic correlate much better with the hyperbolic model (widely used in population biology, demography and macrosociology, as well as fossil biodiversity) than with exponential and logistic models. The latter models imply that changes in diversity are guided by a first-order positive feedback (more ancestors, more descendants) and/or a negative feedback arising from resource limitation. Hyperbolic model implies a second-order positive feedback. The hyperbolic pattern of the world population growth arises from a second-order positive feedback between the population size and the rate of technological growth. The hyperbolic character of biodiversity growth can be similarly accounted for by a feedback between diversity and community structure complexity. The similarity between the curves of biodiversity and human population probably comes from the fact that both are derived from the interference of the hyperbolic trend with cyclical and stochastic dynamics.

Question: What model correlates much better than the hyperbolic model?


Answer: hyperbolic model

Question: What model is widely used in macrosociology?


Answer: exponential and logistic models

Question: What models imply that changes in diversity are guided by a first-order positive feedback?


Answer: Hyperbolic model

Question: What model implies a second-order positive feedback?


Answer: The hyperbolic character of biodiversity growth

Question: What can be accounted for by a feedback between diversity and community structure complexity?


Answer: Interspecific crop diversity

Context: Interspecific crop diversity is, in part, responsible for offering variety in what we eat. Intraspecific diversity, the variety of alleles within a single species, also offers us choice in our diets. If a crop fails in a monoculture, we rely on agricultural diversity to replant the land with something new. If a wheat crop is destroyed by a pest we may plant a hardier variety of wheat the next year, relying on intraspecific diversity. We may forgo wheat production in that area and plant a different species altogether, relying on interspecific diversity. Even an agricultural society which primarily grows monocultures, relies on biodiversity at some point.

Question: What has some responsibility for offering variety in what we eat?


Answer: Interspecific crop diversity

Question: What is the variety of alleles within a single species?


Answer: If a crop fails in a monoculture

Question: When do we rely on agricultural diversity to replant the land with something new?


Answer: a pest

Question: What can destroy a wheat crop?


Answer: agricultural society

Question: What type of a society primarily grows monocultures?


Answer: 52%

Context: In absolute terms, the planet has lost 52% of its biodiversity since 1970 according to a 2014 study by the World Wildlife Fund. The Living Planet Report 2014 claims that "the number of mammals, birds, reptiles, amphibians and fish across the globe is, on average, about half the size it was 40 years ago". Of that number, 39% accounts for the terrestrial wildlife gone, 39% for the marine wildlife gone, and 76% for the freshwater wildlife gone. Biodiversity took the biggest hit in Latin America, plummeting 83 percent. High-income countries showed a 10% increase in biodiversity, which was canceled out by a loss in low-income countries. This is despite the fact that high-income countries use five times the ecological resources of low-income countries, which was explained as a result of process whereby wealthy nations are outsourcing resource depletion to poorer nations, which are suffering the greatest ecosystem losses.

Question: What percentage of biodiversity has the planet lost since 1970


Answer: 2014

Question: What year was they study done by the World Wildlife Fund?


Answer: 39%

Question: What percentage accounts for the terrestrial wildlife gone?


Answer: 39%

Question: What percentage accounts for the marine wildlife gone?


Answer: 76%

Question: What percentage accounts for the freshwater wildlife gone?


Answer: 2007

Context: A 2007 study conducted by the National Science Foundation found that biodiversity and genetic diversity are codependent—that diversity among species requires diversity within a species, and vice versa. "If any one type is removed from the system, the cycle can break down, and the community becomes dominated by a single species." At present, the most threatened ecosystems are found in fresh water, according to the Millennium Ecosystem Assessment 2005, which was confirmed by the "Freshwater Animal Diversity Assessment", organised by the biodiversity platform, and the French Institut de recherche pour le développement (MNHNP).

Question: In which year was the study published that found biodiversity and genetic diversity are codependent?


Answer: National Science Foundation

Question: Who conducted the 2007 study?


Answer: If any one type is removed from the system

Question: What can cause a break down of a biodiversity system?


Answer: in fresh water

Question: Where are the most threatened ecosystems found?


Answer: an introduced species

Context: Finally, an introduced species may unintentionally injure a species that depends on the species it replaces. In Belgium, Prunus spinosa from Eastern Europe leafs much sooner than its West European counterparts, disrupting the feeding habits of the Thecla betulae butterfly (which feeds on the leaves). Introducing new species often leaves endemic and other local species unable to compete with the exotic species and unable to survive. The exotic organisms may be predators, parasites, or may simply outcompete indigenous species for nutrients, water and light.

Question: What may unintentionally injure a species that depends on the species it replaces?


Answer: In Belgium

Question: Where does the Prunus spinosa leaf much sooner?


Answer: leaves endemic and other local species unable to compete with the exotic species and unable to survive

Question: What animal can its feeding habits disturbed by the Prunus spinosa?


Answer: endemic and other local species

Question: What species struggle to with the introduction of new species?


Answer: The exotic organisms may be predators, parasites

Question: What types of new species can be introduced?


Answer: The forests

Context: The forests play a vital role in harbouring more than 45,000 floral and 81,000 faunal species of which 5150 floral and 1837 faunal species are endemic. Plant and animal species confined to a specific geographical area are called endemic species. In reserved forests, rights to activities like hunting and grazing are sometimes given to communities living on the fringes of the forest, who sustain their livelihood partially or wholly from forest resources or products. The unclassed forests covers 6.4 percent of the total forest area and they are marked by the following characteristics:

Question: What plays a vital role in harbouring floral and faunal species?


Answer: 5150

Question: How many endemic floral species do forests harbor?


Answer: 1837

Question: How many endemic faunal species do forests harbor?


Answer: endemic species

Question: What types of animals and plans are confined to a specific geographical area?


Answer: hunting and grazing

Question: What types of activities are granted rights in reserved forests?


Answer: the Convention on Biological Diversity

Context: Global agreements such as the Convention on Biological Diversity, give "sovereign national rights over biological resources" (not property). The agreements commit countries to "conserve biodiversity", "develop resources for sustainability" and "share the benefits" resulting from their use. Biodiverse countries that allow bioprospecting or collection of natural products, expect a share of the benefits rather than allowing the individual or institution that discovers/exploits the resource to capture them privately. Bioprospecting can become a type of biopiracy when such principles are not respected.[citation needed]

Question: What global agreement gives sovereign national rights over biological resources?


Answer: the Convention on Biological Diversity

Question: What agreement commits countries to conserve biodiversity?


Answer: the Convention on Biological Diversity

Question: What agreement commits countries to develop resources for sustainability?


Answer: bioprospecting

Question: What is the process of collecting natural products?


Answer: Rapid environmental changes

Context: Rapid environmental changes typically cause mass extinctions. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described. The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037, and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).

Question: What can typically cause mass extinctions?


Answer: More than 99 percent

Question: What percentage of species is estimated to be extinct?


Answer: over five billion species

Question: How many species have ever lived on earth?


Answer: Earth's current species range from 10 million to 14 million,

Question: How many species currently live on earth?


Answer: 50 billion tonnes

Question: What is the estimated weight of the total amount of related DNA base pairs on Earth?


Answer: the Cambrian explosion

Context: The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, invertebrate diversity showed little overall trend, and vertebrate diversity shows an overall exponential trend. This dramatic rise in diversity was marked by periodic, massive losses of diversity classified as mass extinction events. A significant loss occurred when rainforests collapsed in the carboniferous. The worst was the Permian-Triassic extinction event, 251 million years ago. Vertebrates took 30 million years to recover from this event.

Question: Which era included a rapid growth period?


Answer: the last 540 million years

Question: The Phanerozoic era covers what time period?


Answer: the Cambrian explosion

Question: In which era, did the first phylum of multicellular organisms appear?


Answer: vertebrate diversity

Question: What type of diversity showed an overall exponential trend?


Answer: the Permian-Triassic extinction event

Question: In which event did the rainforests collapsed in the carboniferous?


Answer: Jared Diamond

Context: Jared Diamond describes an "Evil Quartet" of habitat destruction, overkill, introduced species, and secondary extinctions. Edward O. Wilson prefers the acronym HIPPO, standing for Habitat destruction, Invasive species, Pollution, human over-Population, and Over-harvesting. The most authoritative classification in use today is IUCN's Classification of Direct Threats which has been adopted by major international conservation organizations such as the US Nature Conservancy, the World Wildlife Fund, Conservation International, and BirdLife International.

Question: Who describes the "Evil Quartet"?


Answer: Evil Quartet

Question: What describes habitat destruction, overkill, introduced species, and secondary extinctions?


Answer: HIPPO

Question: What describes Habitat destruction, Invasive species, Pollution, human over-Population, and Over-harvesting?


Answer: IUCN's Classification of Direct Threats

Question: What is the most authoritative classification in use today?


Answer: the World Wildlife Fund

Question: What funding organization uses the IUCN's Classification of Direct Threats?


Answer: genetic pollution

Context: Endemic species can be threatened with extinction through the process of genetic pollution, i.e. uncontrolled hybridization, introgression and genetic swamping. Genetic pollution leads to homogenization or replacement of local genomes as a result of either a numerical and/or fitness advantage of an introduced species. Hybridization and introgression are side-effects of introduction and invasion. These phenomena can be especially detrimental to rare species that come into contact with more abundant ones. The abundant species can interbreed with the rare species, swamping its gene pool. This problem is not always apparent from morphological (outward appearance) observations alone. Some degree of gene flow is normal adaptation, and not all gene and genotype constellations can be preserved. However, hybridization with or without introgression may, nevertheless, threaten a rare species' existence.

Question: What can threaten endemic species with extinction?


Answer: uncontrolled hybridization, introgression and genetic swamping

Question: What are another names for genetic pollution?


Answer: either a numerical and/or fitness advantage of an introduced species

Question: What causes genetic pollution?


Answer: Hybridization and introgression

Question: What are are side-effects of introduction and invasion?


Answer: The abundant species can interbreed with the rare species

Question: What behavior causes swamping of a gene pool?


Answer: about 4.54 billion years old

Context: The age of the Earth is about 4.54 billion years old. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, during the Eoarchean Era after a geological crust started to solidify following the earlier molten Hadean Eon. There are microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia. Other early physical evidence of a biogenic substance is graphite in 3.7 billion-year-old metasedimentary rocks discovered in Western Greenland. More recently, in 2015, "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. According to one of the researchers, "If life arose relatively quickly on Earth ... then it could be common in the universe."

Question: What is the estimate age of the Earth?


Answer: the Eoarchean Era

Question: What era contains the earliest undisputed evidence of life on Earth?


Answer: Hadean Eon

Question: What is the name of the era that predated life on Earth?


Answer: Western Australia

Question: Where were the billion year old microbial mat fossils found?


Answer: Western Greenland

Question: Where were the 3.7 billion-year-old metasedimentary rocks discovered?


Answer: The fossil record

Context: The fossil record suggests that the last few million years featured the greatest biodiversity in history. However, not all scientists support this view, since there is uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections. Some scientists believe that corrected for sampling artifacts, modern biodiversity may not be much different from biodiversity 300 million years ago., whereas others consider the fossil record reasonably reflective of the diversification of life. Estimates of the present global macroscopic species diversity vary from 2 million to 100 million, with a best estimate of somewhere near 9 million, the vast majority arthropods. Diversity appears to increase continually in the absence of natural selection.

Question: What suggests that the last few million years featured the greatest biodiversity in history?


Answer: how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections.

Question: Why are some scientists uncertain about the fossil record?


Answer: from 2 million to 100 million

Question: What is the estimate variation of the present global macroscopic species diversity?


Answer: Diversity

Question: What appears increase continually in the absence of natural selection?


Answer: ‘planned’ diversity or ‘associated’ diversity

Context: Agricultural diversity can also be divided by whether it is ‘planned’ diversity or ‘associated’ diversity. This is a functional classification that we impose and not an intrinsic feature of life or diversity. Planned diversity includes the crops which a farmer has encouraged, planted or raised (e.g.: crops, covers, symbionts and livestock, among others), which can be contrasted with the associated diversity that arrives among the crops, uninvited (e.g.: herbivores, weed species and pathogens, among others).

Question: What are two types of Agricultural diversity?


Answer: Planned diversity

Question: What type of diversity includes the crops which a farmer has encouraged, planted or raised?


Answer: associated diversity

Question: What type of diversity arrives uninvited?


Answer: associated diversity

Question: What type of diversity includes herbivores and pathogens?


Answer: Biodiversity's relevance to human health

Context: Biodiversity's relevance to human health is becoming an international political issue, as scientific evidence builds on the global health implications of biodiversity loss. This issue is closely linked with the issue of climate change, as many of the anticipated health risks of climate change are associated with changes in biodiversity (e.g. changes in populations and distribution of disease vectors, scarcity of fresh water, impacts on agricultural biodiversity and food resources etc.) This is because the species most likely to disappear are those that buffer against infectious disease transmission, while surviving species tend to be the ones that increase disease transmission, such as that of West Nile Virus, Lyme disease and Hantavirus, according to a study done co-authored by Felicia Keesing, an ecologist at Bard College, and Drew Harvell, associate director for Environment of the Atkinson Center for a Sustainable Future (ACSF) at Cornell University.

Question: What is becoming an international political issue?


Answer: climate change

Question: What issue is closely linked with changes in biodiversity?


Answer: changes in populations and distribution of disease vectors, scarcity of fresh water, impacts on agricultural biodiversity and food resources

Question: What changes in biodiversity have an effect on the climate?


Answer: those that buffer against infectious disease transmission

Question: What types of species disappear when a new disease is introduced?


Answer: five major mass extinctions

Context: Since life began on Earth, five major mass extinctions and several minor events have led to large and sudden drops in biodiversity. The Phanerozoic eon (the last 540 million years) marked a rapid growth in biodiversity via the Cambrian explosion—a period during which the majority of multicellular phyla first appeared. The next 400 million years included repeated, massive biodiversity losses classified as mass extinction events. In the Carboniferous, rainforest collapse led to a great loss of plant and animal life. The Permian–Triassic extinction event, 251 million years ago, was the worst; vertebrate recovery took 30 million years. The most recent, the Cretaceous–Paleogene extinction event, occurred 65 million years ago and has often attracted more attention than others because it resulted in the extinction of the dinosaurs.

Question: How many mass extinctions have happened since Life began on Earth?


Answer: the Cambrian explosion

Question: When was the period where the majority of multicellular phyla first appeared?


Answer: rainforest collapse led to a great loss of plant and animal life.

Question: What happened in the Carboniferous?


Answer: 251 million years ago

Question: When was the Permian–Triassic extinction event?


Answer: 30 million years

Question: How long did vertebrate recovery take?


Answer: 1900s

Context: The number of species invasions has been on the rise at least since the beginning of the 1900s. Species are increasingly being moved by humans (on purpose and accidentally). In some cases the invaders are causing drastic changes and damage to their new habitats (e.g.: zebra mussels and the emerald ash borer in the Great Lakes region and the lion fish along the North American Atlantic coast). Some evidence suggests that invasive species are competitive in their new habitats because they are subject to less pathogen disturbance. Others report confounding evidence that occasionally suggest that species-rich communities harbor many native and exotic species simultaneously while some say that diverse ecosystems are more resilient and resist invasive plants and animals. An important question is, "do invasive species cause extinctions?" Many studies cite effects of invasive species on natives, but not extinctions. Invasive species seem to increase local (i.e.: alpha diversity) diversity, which decreases turnover of diversity (i.e.: beta diversity). Overall gamma diversity may be lowered because species are going extinct because of other causes, but even some of the most insidious invaders (e.g.: Dutch elm disease, emerald ash borer, chestnut blight in North America) have not caused their host species to become extinct. Extirpation, population decline, and homogenization of regional biodiversity are much more common. Human activities have frequently been the cause of invasive species circumventing their barriers, by introducing them for food and other purposes. Human activities therefore allow species to migrate to new areas (and thus become invasive) occurred on time scales much shorter than historically have been required for a species to extend its range.

Question: What century started the increase of species invasions?


Answer: humans

Question: Who intentionally and unintentionally moves species around?


Answer: zebra mussels and the emerald ash borer

Question: What invaders are causing changes in the Great Lakes region?


Answer: lion fish

Question: What invaders are causing changes along the North American Atlantic coast?


Answer: 20,000 plant species

Context: Brazil's Atlantic Forest is considered one such hotspot, containing roughly 20,000 plant species, 1,350 vertebrates, and millions of insects, about half of which occur nowhere else.[citation needed] The island of Madagascar and India are also particularly notable. Colombia is characterized by high biodiversity, with the highest rate of species by area unit worldwide and it has the largest number of endemics (species that are not found naturally anywhere else) of any country. About 10% of the species of the Earth can be found in Colombia, including over 1,900 species of bird, more than in Europe and North America combined, Colombia has 10% of the world’s mammals species, 14% of the amphibian species, and 18% of the bird species of the world. Madagascar dry deciduous forests and lowland rainforests possess a high ratio of endemism.[citation needed] Since the island separated from mainland Africa 66 million years ago, many species and ecosystems have evolved independently.[citation needed] Indonesia's 17,000 islands cover 735,355 square miles (1,904,560 km2) and contain 10% of the world's flowering plants, 12% of mammals, and 17% of reptiles, amphibians and birds—along with nearly 240 million people. Many regions of high biodiversity and/or endemism arise from specialized habitats which require unusual adaptations, for example, alpine environments in high mountains, or Northern European peat bogs.[citation needed]

Question: How many plant species does Brazil's Atlantic Forest contain?


Answer: 1,350 vertebrates

Question: How many vertebrates does Brazil's Atlantic Forest contain?


Answer: Colombia

Question: Which country has the highest rate of species by area unit worldwide?


Answer: Colombia

Question: Which country has about 10% of the species on Earth?


Answer: Madagascar

Question: What island separated from mainland Africa 66 million years ago?


Answer: global carrying capacity

Context: The existence of a "global carrying capacity", limiting the amount of life that can live at once, is debated, as is the question of whether such a limit would also cap the number of species. While records of life in the sea shows a logistic pattern of growth, life on land (insects, plants and tetrapods)shows an exponential rise in diversity. As one author states, "Tetrapods have not yet invaded 64 per cent of potentially habitable modes, and it could be that without human influence the ecological and taxonomic diversity of tetrapods would continue to increase in an exponential fashion until most or all of the available ecospace is filled."

Question: What limits the amount of life that can live at once on Earth?


Answer: life in the sea

Question: What type of animal shows a logistic pattern of growth?


Answer: life on land

Question: What type of animal shows an exponential rise in diversity?


Answer: 64 per cent

Question: What percentage of potentially habitable modes have Tetrapods not yet invaded?


Answer: world population increased from 2.5 billion to 7 billion

Context: From 1950 to 2011, world population increased from 2.5 billion to 7 billion and is forecast to reach a plateau of more than 9 billion during the 21st century. Sir David King, former chief scientific adviser to the UK government, told a parliamentary inquiry: "It is self-evident that the massive growth in the human population through the 20th century has had more impact on biodiversity than any other single factor." At least until the middle of the 21st century, worldwide losses of pristine biodiverse land will probably depend much on the worldwide human birth rate.

Question: What was the increase in population from 1950 to 2011?


Answer: From 1950

Question: What year started the increase of population to 7 billion?


Answer: more than 9 billion

Question: What is the forecast plateau that the population will reach during the 21st century?


Answer: Sir David King

Question: Who is the former chief scientific adviser to the UK government?


Answer: monoculture farms

Context: The control of associated biodiversity is one of the great agricultural challenges that farmers face. On monoculture farms, the approach is generally to eradicate associated diversity using a suite of biologically destructive pesticides, mechanized tools and transgenic engineering techniques, then to rotate crops. Although some polyculture farmers use the same techniques, they also employ integrated pest management strategies as well as strategies that are more labor-intensive, but generally less dependent on capital, biotechnology and energy.

Question: What farms use biologically destructive pesticides


Answer: The control of associated biodiversity

Question: What is one of the great agricultural challenges that farmers face?


Answer: polyculture farmers

Question: What farmers use integrated pest management strategies?


Answer: polyculture farmers

Question: What farmers are generally less dependent on capital, biotechnology and energy?


Answer: National park and nature reserve

Context: National park and nature reserve is the area selected by governments or private organizations for special protection against damage or degradation with the objective of biodiversity and landscape conservation. National parks are usually owned and managed by national or state governments. A limit is placed on the number of visitors permitted to enter certain fragile areas. Designated trails or roads are created. The visitors are allowed to enter only for study, cultural and recreation purposes. Forestry operations, grazing of animals and hunting of animals are prohibited. Exploitation of habitat or wildlife is banned.

Question: What types of parks receive special protection against damage or degradation?


Answer: governments or private organizations

Question: Who selects National parks?


Answer: with the objective of biodiversity and landscape conservation

Question: What is the goal of protecting National Parks from damage?


Answer: national or state governments

Question: Who usually owns and manages National parks?


Answer: Forestry operations, grazing of animals and hunting of animals

Question: What activities are prohibited in national parks?


Answer: Sigmar Gabriel

Context: During the last century, decreases in biodiversity have been increasingly observed. In 2007, German Federal Environment Minister Sigmar Gabriel cited estimates that up to 30% of all species will be extinct by 2050. Of these, about one eighth of known plant species are threatened with extinction. Estimates reach as high as 140,000 species per year (based on Species-area theory). This figure indicates unsustainable ecological practices, because few species emerge each year.[citation needed] Almost all scientists acknowledge that the rate of species loss is greater now than at any time in human history, with extinctions occurring at rates hundreds of times higher than background extinction rates. As of 2012, some studies suggest that 25% of all mammal species could be extinct in 20 years.

Question: Who is the German Federal Environment Minister?


Answer: 2050

Question: What year did Gabriel estimate 30% of of all species will be extinct by?


Answer: about one eighth

Question: How many plant species are close to extinction?


Answer: 25%

Question: 2012 studies estimated what percentage of mammals could be extinct in 20 years?


Answer: Habitat size

Context: Habitat size and numbers of species are systematically related. Physically larger species and those living at lower latitudes or in forests or oceans are more sensitive to reduction in habitat area. Conversion to "trivial" standardized ecosystems (e.g., monoculture following deforestation) effectively destroys habitat for the more diverse species that preceded the conversion. In some countries lack of property rights or lax law/regulatory enforcement necessarily leads to biodiversity loss (degradation costs having to be supported by the community).[citation needed]

Question: What is systematically related to the numbers of species?


Answer: Physically larger species and those living at lower latitudes or in forests or oceans

Question: What animals are more sensitive to reduction in habitat area?


Answer: monoculture following deforestation

Question: How is a standardized ecosystem formed?


Answer: lack of property rights or lax law/regulatory enforcement

Question: What leads to biodiversity loss is some countries?


Answer: the zebra mussel

Context: Not all introduced species are invasive, nor all invasive species deliberately introduced. In cases such as the zebra mussel, invasion of US waterways was unintentional. In other cases, such as mongooses in Hawaii, the introduction is deliberate but ineffective (nocturnal rats were not vulnerable to the diurnal mongoose). In other cases, such as oil palms in Indonesia and Malaysia, the introduction produces substantial economic benefits, but the benefits are accompanied by costly unintended consequences.

Question: What animal unintentionally invaded the US waterways?


Answer: mongooses

Question: What animal intentionally invaded Hawaii?


Answer: nocturnal rats

Question: What animals were not vulnerable to the mongoose?


Answer: Indonesia and Malaysia,

Question: What countries experienced unintended consequences from species invasion?


Answer: Contemporary biodiversity physics

Context: Less than 1% of all species that have been described have been studied beyond simply noting their existence. The vast majority of Earth's species are microbial. Contemporary biodiversity physics is "firmly fixated on the visible [macroscopic] world". For example, microbial life is metabolically and environmentally more diverse than multicellular life (see e.g., extremophile). "On the tree of life, based on analyses of small-subunit ribosomal RNA, visible life consists of barely noticeable twigs. The inverse relationship of size and population recurs higher on the evolutionary ladder—"to a first approximation, all multicellular species on Earth are insects". Insect extinction rates are high—supporting the Holocene extinction hypothesis.

Question: What type of science is firmly fixated on the visible world?


Answer: microbial life

Question: What type of life is more metabolically diverse than multicellular life?


Answer: microbial life

Question: What type of life is more enviromentally diverse than multicellular life?


Answer: Insect extinction rates

Question: What rate supports the Holocene extinction hypothesis?


Answer: biodiversity

Context: The number and variety of plants, animals and other organisms that exist is known as biodiversity. It is an essential component of nature and it ensures the survival of human species by providing food, fuel, shelter, medicines and other resources to mankind. The richness of biodiversity depends on the climatic conditions and area of the region. All species of plants taken together are known as flora and about 70,000 species of plants are known till date. All species of animals taken together are known as fauna which includes birds, mammals, fish, reptiles, insects, crustaceans, molluscs, etc.

Question: What term describes the number and variety of plants, animals and other organisms in existence?


Answer: biodiversity

Question: What ensures the survival of human species by providing food, shelter, other resources to mankind?


Answer: the climatic conditions and area of the region

Question: What influences richness of biodiversity?


Answer: flora

Question: What term describes all the species of plants in existence?


Answer: Raymond F. Dasmann

Context: The term biological diversity was used first by wildlife scientist and conservationist Raymond F. Dasmann in the year 1968 lay book A Different Kind of Country advocating conservation. The term was widely adopted only after more than a decade, when in the 1980s it came into common usage in science and environmental policy. Thomas Lovejoy, in the foreword to the book Conservation Biology, introduced the term to the scientific community. Until then the term "natural diversity" was common, introduced by The Science Division of The Nature Conservancy in an important 1975 study, "The Preservation of Natural Diversity." By the early 1980s TNC's Science program and its head, Robert E. Jenkins, Lovejoy and other leading conservation scientists at the time in America advocated the use of the term "biological diversity".

Question: Which scientist first used the term biological diversity?


Answer: A Different Kind of Country

Question: What book first contained the term biological diversity?


Answer: the 1980s

Question: What decade did the term biological diversity become common usage in science and economics?


Answer: Thomas Lovejoy

Question: Who introduced the term biological diversity to the scientific community?


Answer: "natural diversity"

Question: What term was common before biological diversity?


Answer: Biodiversity

Context: Biodiversity provides critical support for drug discovery and the availability of medicinal resources. A significant proportion of drugs are derived, directly or indirectly, from biological sources: at least 50% of the pharmaceutical compounds on the US market are derived from plants, animals, and micro-organisms, while about 80% of the world population depends on medicines from nature (used in either modern or traditional medical practice) for primary healthcare. Only a tiny fraction of wild species has been investigated for medical potential. Biodiversity has been critical to advances throughout the field of bionics. Evidence from market analysis and biodiversity science indicates that the decline in output from the pharmaceutical sector since the mid-1980s can be attributed to a move away from natural product exploration ("bioprospecting") in favor of genomics and synthetic chemistry, indeed claims about the value of undiscovered pharmaceuticals may not provide enough incentive for companies in free markets to search for them because of the high cost of development; meanwhile, natural products have a long history of supporting significant economic and health innovation. Marine ecosystems are particularly important, although inappropriate bioprospecting can increase biodiversity loss, as well as violating the laws of the communities and states from which the resources are taken.

Question: What provides critical support for drug discovery and the availability of medicinal resources?


Answer: at least 50%

Question: What percentage of US drugs are derived from plants, animals, and micro-organisms?


Answer: bionics

Question: What field has biodiversity made critical advances in?


Answer: about 80%

Question: What percentage of worldwide drugs are derived from nature?


Answer: the Green Revolution

Context: In agriculture and animal husbandry, the Green Revolution popularized the use of conventional hybridization to increase yield. Often hybridized breeds originated in developed countries and were further hybridized with local varieties in the developing world to create high yield strains resistant to local climate and diseases. Local governments and industry have been pushing hybridization. Formerly huge gene pools of various wild and indigenous breeds have collapsed causing widespread genetic erosion and genetic pollution. This has resulted in loss of genetic diversity and biodiversity as a whole.

Question: What popularized the use of conventional hybridization to increase yield?


Answer: local climate and diseases

Question: What did the high yield strains become resistant to?


Answer: Local governments and industry

Question: Who has been pushing for hybridization?


Answer: Formerly huge gene pools of various wild and indigenous breeds have collapsed causing widespread genetic erosion

Question: What caused the loss of biodiversity?


Answer: English alphabet

Context: Originally based on the English alphabet, ASCII encodes 128 specified characters into seven-bit integers as shown by the ASCII chart on the right. The characters encoded are numbers 0 to 9, lowercase letters a to z, uppercase letters A to Z, basic punctuation symbols, control codes that originated with Teletype machines, and a space. For example, lowercase j would become binary 1101010 and decimal 106. ASCII includes definitions for 128 characters: 33 are non-printing control characters (many now obsolete) that affect how text and space are processed and 95 printable characters, including the space (which is considered an invisible graphic:223).

Question: What is the ASCII based on?


Answer: 128 specified characters

Question: How many specific characters are there in the ASCII code?


Answer: 33 are non-printing control characters

Question: How many are non-printing control characters?


Answer: 95 printable characters

Question: How many characters are printable characters?


Answer: invisible graphic:223

Question: What is the space also known as what?


Answer: for ease of identification

Context: The code itself was patterned so that most control codes were together, and all graphic codes were together, for ease of identification. The first two columns (32 positions) were reserved for control characters.:220, 236 § 8,9) The "space" character had to come before graphics to make sorting easier, so it became position 20hex;:237 § 10 for the same reason, many special signs commonly used as separators were placed before digits. The committee decided it was important to support uppercase 64-character alphabets, and chose to pattern ASCII so it could be reduced easily to a usable 64-character set of graphic codes,:228, 237 § 14 as was done in the DEC SIXBIT code. Lowercase letters were therefore not interleaved with uppercase. To keep options available for lowercase letters and other graphics, the special and numeric codes were arranged before the letters, and the letter A was placed in position 41hex to match the draft of the corresponding British standard.:238 § 18 The digits 0–9 were arranged so they correspond to values in binary prefixed with 011, making conversion with binary-coded decimal straightforward.

Question: Why was the code patterned so that most codes were together?


Answer: 32 positions

Question: How many positions are in the first two columns?


Answer: to support uppercase 64-character alphabets

Question: What did the committee decide was important?


Answer: 41hex

Question: Where was the letter A places in position?


Answer: Unicode

Context: ASCII was incorporated into the Unicode character set as the first 128 symbols, so the 7-bit ASCII characters have the same numeric codes in both sets. This allows UTF-8 to be backward compatible with 7-bit ASCII, as a UTF-8 file containing only ASCII characters is identical to an ASCII file containing the same sequence of characters. Even more importantly, forward compatibility is ensured as software that recognizes only 7-bit ASCII characters as special and does not alter bytes with the highest bit set (as is often done to support 8-bit ASCII extensions such as ISO-8859-1) will preserve UTF-8 data unchanged.

Question: ASCII was incorporated into what other character set?


Answer: 128 symbols

Question: How many of the symbols are the same in the beginning of the ASCII and Unicode?


Answer: UTF-8

Question: What set is backward compatible with 7-bit ASCII?


Answer: a Control-S

Context: When a Teletype 33 ASR equipped with the automatic paper tape reader received a Control-S (XOFF, an abbreviation for transmit off), it caused the tape reader to stop; receiving Control-Q (XON, "transmit on") caused the tape reader to resume. This technique became adopted by several early computer operating systems as a "handshaking" signal warning a sender to stop transmission because of impending overflow; it persists to this day in many systems as a manual output control technique. On some systems Control-S retains its meaning but Control-Q is replaced by a second Control-S to resume output. The 33 ASR also could be configured to employ Control-R (DC2) and Control-T (DC4) to start and stop the tape punch; on some units equipped with this function, the corresponding control character lettering on the keycap above the letter was TAPE and TAPE respectively.

Question: What casued the automatic paper tape reader to stop?


Answer: Control-Q

Question: What caused the automatic paper tape reader to start again?


Answer: handshaking

Question: What was the warning signal called that warned the sender that there was impending overflow?


Answer: Control-R (DC2) and Control-T (DC4)

Question: What two controls can be configured with 33 ASR?


Answer: CRTs or terminals

Context: DEC operating systems (OS/8, RT-11, RSX-11, RSTS, TOPS-10, etc.) used both characters to mark the end of a line so that the console device (originally Teletype machines) would work. By the time so-called "glass TTYs" (later called CRTs or terminals) came along, the convention was so well established that backward compatibility necessitated continuing the convention. When Gary Kildall cloned RT-11 to create CP/M he followed established DEC convention. Until the introduction of PC DOS in 1981, IBM had no hand in this because their 1970s operating systems used EBCDIC instead of ASCII and they were oriented toward punch-card input and line printer output on which the concept of carriage return was meaningless. IBM's PC DOS (also marketed as MS-DOS by Microsoft) inherited the convention by virtue of being a clone of CP/M, and Windows inherited it from MS-DOS.

Question: What are glass TTYs also known as?


Answer: RT-11

Question: What did Gary Kildall clone to create CP/M?


Answer: 1981

Question: When was the introduction of PC DOS?


Answer: EBCDIC

Question: What programming did IBM use in the 1970s?


Answer: MS-DOS

Question: What was IBM's PC DOS marketed as by Microsoft?


Answer: C trigraphs

Context: C trigraphs were created to solve this problem for ANSI C, although their late introduction and inconsistent implementation in compilers limited their use. Many programmers kept their computers on US-ASCII, so plain-text in Swedish, German etc. (for example, in e-mail or Usenet) contained "{, }" and similar variants in the middle of words, something those programmers got used to. For example, a Swedish programmer mailing another programmer asking if they should go for lunch, could get "N{ jag har sm|rg}sar." as the answer, which should be "Nä jag har smörgåsar." meaning "No I've got sandwiches."

Question: What was created to solve the problem for ANSI C?


Answer: their late introduction and inconsistent implementation in compilers

Question: Why was their use limited?


Answer: US-ASCII

Question: What did many programmers keep their computers on?


Answer: contained "{, }" and similar variants in the middle of words

Question: What what happening to the words that were sent from programmers?


Answer: teleprinter encoding systems

Context: The X3.2 subcommittee designed ASCII based on the earlier teleprinter encoding systems. Like other character encodings, ASCII specifies a correspondence between digital bit patterns and character symbols (i.e. graphemes and control characters). This allows digital devices to communicate with each other and to process, store, and communicate character-oriented information such as written language. Before ASCII was developed, the encodings in use included 26 alphabetic characters, 10 numerical digits, and from 11 to 25 special graphic symbols. To include all these, and control characters compatible with the Comité Consultatif International Téléphonique et Télégraphique (CCITT) International Telegraph Alphabet No. 2 (ITA2) standard, Fieldata, and early EBCDIC, more than 64 codes were required for ASCII.

Question: What was ASCII based on?


Answer: digital bit patterns and character symbols

Question: ASCII specifies correspondence between what?


Answer: communicate with each other and to process, store, and communicate character-oriented information

Question: What does ASCII correspondence allow digital devices to do?


Answer: 11 to 25 special graphic symbols

Question: How many graphic symbols were used before ASCII?


Answer: more than 64 codes

Question: How many codes were required for ASCII?


Answer: 1963

Context: ASCII itself was first used commercially during 1963 as a seven-bit teleprinter code for American Telephone & Telegraph's TWX (TeletypeWriter eXchange) network. TWX originally used the earlier five-bit ITA2, which was also used by the competing Telex teleprinter system. Bob Bemer introduced features such as the escape sequence. His British colleague Hugh McGregor Ross helped to popularize this work – according to Bemer, "so much so that the code that was to become ASCII was first called the Bemer-Ross Code in Europe". Because of his extensive work on ASCII, Bemer has been called "the father of ASCII."

Question: When was ASCII first commercially used?


Answer: a seven-bit teleprinter code for American Telephone & Telegraph's TWX (TeletypeWriter eXchange) network

Question: What was it used for?


Answer: five-bit ITA2

Question: What did TWX use before ASCII?


Answer: Bob Bemer

Question: Who is the father of ASCII?


Answer: Bemer-Ross Code

Question: What was the code first called in Europe?


Answer: causes a printer to advance its paper

Context: For example, character 10 represents the "line feed" function (which causes a printer to advance its paper), and character 8 represents "backspace". RFC 2822 refers to control characters that do not include carriage return, line feed or white space as non-whitespace control characters. Except for the control characters that prescribe elementary line-oriented formatting, ASCII does not define any mechanism for describing the structure or appearance of text within a document. Other schemes, such as markup languages, address page and document layout and formatting.

Question: What does the "line feed" function do?


Answer: character 10

Question: What character represents the "line feed" function?


Answer: backspace

Question: What does character 8 represent?


Answer: control characters that do not include carriage return, line feed or white space as non-whitespace control characters

Question: What does RFC 2822 refers to what kind of control characters?


Answer: assigned special meanings

Context: Some software assigned special meanings to ASCII characters sent to the software from the terminal. Operating systems from Digital Equipment Corporation, for example, interpreted DEL as an input character as meaning "remove previously-typed input character", and this interpretation also became common in Unix systems. Most other systems used BS for that meaning and used DEL to mean "remove the character at the cursor".[citation needed] That latter interpretation is the most common now.[citation needed]

Question: What did some software do to the ASCII characters?


Answer: interpreted DEL as an input character as meaning "remove previously-typed input character"

Question: What interpretation became common in Unix systmes?


Answer: remove the character at the cursor

Question: What do most other systmes use the DEL to mean?


Answer: BS

Question: What did other systmes us for "remove previously-typed input character"?


Answer: CR-LF

Context: Computers attached to the ARPANET included machines running operating systems such as TOPS-10 and TENEX using CR-LF line endings, machines running operating systems such as Multics using LF line endings, and machines running operating systems such as OS/360 that represented lines as a character count followed by the characters of the line and that used EBCDIC rather than ASCII. The Telnet protocol defined an ASCII "Network Virtual Terminal" (NVT), so that connections between hosts with different line-ending conventions and character sets could be supported by transmitting a standard text format over the network. Telnet used ASCII along with CR-LF line endings, and software using other conventions would translate between the local conventions and the NVT. The File Transfer Protocol adopted the Telnet protocol, including use of the Network Virtual Terminal, for use when transmitting commands and transferring data in the default ASCII mode. This adds complexity to implementations of those protocols, and to other network protocols, such as those used for E-mail and the World Wide Web, on systems not using the NVT's CR-LF line-ending convention.

Question: What do computers attached to the ARPANET use for line endings?


Answer: by transmitting a standard text format over the network

Question: How were the connections supported?


Answer: The File Transfer Protocol

Question: Who else adopted this practice from Telnet?


Answer: so that connections between hosts with different line-ending conventions and character sets could be supported

Question: Why did Telnet define an ASCII as a Network Virtual Terminal?


Answer: LF

Question: What do computers using operating systems use for line endings?


Answer: 1972

Context: From early in its development, ASCII was intended to be just one of several national variants of an international character code standard, ultimately published as ISO/IEC 646 (1972), which would share most characters in common but assign other locally useful characters to several code points reserved for "national use." However, the four years that elapsed between the publication of ASCII-1963 and ISO's first acceptance of an international recommendation during 1967 caused ASCII's choices for the national use characters to seem to be de facto standards for the world, causing confusion and incompatibility once other countries did begin to make their own assignments to these code points.

Question: When was ISO/IEC 646 published?


Answer: one of several national variants of an international character code standard

Question: What was ASCII inteded to be?


Answer: 1967

Question: When was ISO's first acceptance of an international recommendation?


Answer: ASCII's choices for the national use characters to seem to be de facto standards for the world

Question: What was causing the confusion and incompatibility of the code points?


Answer: their own 8-bit character sets

Context: Most early home computer systems developed their own 8-bit character sets containing line-drawing and game glyphs, and often filled in some or all of the control characters from 0–31 with more graphics. Kaypro CP/M computers used the "upper" 128 characters for the Greek alphabet. The IBM PC defined code page 437, which replaced the control-characters with graphic symbols such as smiley faces, and mapped additional graphic characters to the upper 128 positions. Operating systems such as DOS supported these code pages, and manufacturers of IBM PCs supported them in hardware. Digital Equipment Corporation developed the Multinational Character Set (DEC-MCS) for use in the popular VT220 terminal as one of the first extensions designed more for international languages than for block graphics. The Macintosh defined Mac OS Roman and Postscript also defined a set, both of these contained both international letters and typographic punctuation marks instead of graphics, more like modern character sets.

Question: What did most early home computers develop?


Answer: the "upper" 128 characters for the Greek alphabet

Question: What did Kaypro CP/M computers use?


Answer: graphic symbols such as smiley faces

Question: What did IBM PC replace the control-characters with?


Answer: Multinational Character Set (DEC-MCS)

Question: What did Digital Equipment Corporation develop?


Answer: typographic punctuation marks

Question: What did Macintosh use instead of graphics?


Answer: UTF-8

Context: ASCII (i/ˈæski/ ASS-kee), abbreviated from American Standard Code for Information Interchange, is a character-encoding scheme (the IANA prefers the name US-ASCII). ASCII codes represent text in computers, communications equipment, and other devices that use text. Most modern character-encoding schemes are based on ASCII, though they support many additional characters. ASCII was the most common character encoding on the World Wide Web until December 2007, when it was surpassed by UTF-8, which is fully backward compatibe to ASCII.

Question: Who surpassed ASCII?


Answer: December 2007

Question: ASCI was the most common character encoding on the world wide web until when?


Answer: is a character-encoding scheme

Question: What is the definition of ASCII?


Answer: text in computers, communications equipment, and other devices that use text

Question: What does ASCII code represent?


Answer: American Standard Code for Information Interchange

Question: What does ASCII stand for?


Answer: ASCII required at least a seven-bit code

Context: The committee debated the possibility of a shift function (like in ITA2), which would allow more than 64 codes to be represented by a six-bit code. In a shifted code, some character codes determine choices between options for the following character codes. It allows compact encoding, but is less reliable for data transmission as an error in transmitting the shift code typically makes a long part of the transmission unreadable. The standards committee decided against shifting, and so ASCII required at least a seven-bit code.:215, 236 § 4

Question: What happened after they decided agasint shifting?


Answer: would allow more than 64 codes to be represented by a six-bit code

Question: Why did the committee debate adding a shift function?


Answer: some character codes determine choices between options for the following character codes

Question: What is different in a shifted code?


Answer: less reliable for data transmission as an error in transmitting the shift code typically makes a long part of the transmission unreadable

Question: Why did they decide against shifting code?


Answer: to allow sending other control characters as literals instead of invoking their meaning

Context: Many more of the control codes have been given meanings quite different from their original ones. The "escape" character (ESC, code 27), for example, was intended originally to allow sending other control characters as literals instead of invoking their meaning. This is the same meaning of "escape" encountered in URL encodings, C language strings, and other systems where certain characters have a reserved meaning. Over time this meaning has been co-opted and has eventually been changed. In modern use, an ESC sent to the terminal usually indicates the start of a command sequence, usually in the form of a so-called "ANSI escape code" (or, more properly, a "Control Sequence Introducer") beginning with ESC followed by a "[" (left-bracket) character. An ESC sent from the terminal is most often used as an out-of-band character used to terminate an operation, as in the TECO and vi text editors. In graphical user interface (GUI) and windowing systems, ESC generally causes an application to abort its current operation or to exit (terminate) altogether.

Question: What was the "escape" character originally intended for?


Answer: most often used as an out-of-band character used to terminate an operation

Question: What does modern ESC code do?


Answer: an application to abort its current operation or to exit (terminate) altogether

Question: What does ESC generally mean for graphical user interfaces and windowing systems?


Answer: end-of-file

Context: Older operating systems such as TOPS-10, along with CP/M, tracked file length only in units of disk blocks and used Control-Z (SUB) to mark the end of the actual text in the file. For this reason, EOF, or end-of-file, was used colloquially and conventionally as a three-letter acronym for Control-Z instead of SUBstitute. The end-of-text code (ETX), also known as Control-C, was inappropriate for a variety of reasons, while using Z as the control code to end a file is analogous to it ending the alphabet and serves as a very convenient mnemonic aid. A historically common and still prevalent convention uses the ETX code convention to interrupt and halt a program via an input data stream, usually from a keyboard.

Question: What does EOF stand for?


Answer: to interrupt and halt a program via an input data stream, usually from a keyboard

Question: What is still the conventional use of the ETX code?


Answer: Control-Z (SUB)

Question: What did older operating systems use to mark the end of the text?


Answer: Control-C

Question: What else is the end-of-text code known as?


Answer: telegraphic codes

Context: ASCII developed from telegraphic codes. Its first commercial use was as a seven-bit teleprinter code promoted by Bell data services. Work on the ASCII standard began on October 6, 1960, with the first meeting of the American Standards Association's (ASA) X3.2 subcommittee. The first edition of the standard was published during 1963, underwent a major revision during 1967, and experienced its most recent update during 1986. Compared to earlier telegraph codes, the proposed Bell code and ASCII were both ordered for more convenient sorting (i.e., alphabetization) of lists, and added features for devices other than teleprinters.

Question: What was ASCII developed from?


Answer: a seven-bit teleprinter code promoted by Bell data services

Question: What was the first commercial use of ASCII?


Answer: October 6, 1960

Question: When did work on the ASCII standard begin?


Answer: 1963

Question: When was the first edition of the standard published?


Answer: 1967

Question: When was the first major revision of the code done?


Answer: eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal

Context: The committee considered an eight-bit code, since eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal. However, it would require all data transmission to send eight bits when seven could suffice. The committee voted to use a seven-bit code to minimize costs associated with data transmission. Since perforated tape at the time could record eight bits in one position, it also allowed for a parity bit for error checking if desired.:217, 236 § 5 Eight-bit machines (with octets as the native data type) that did not use parity checking typically set the eighth bit to 0.

Question: Why did the committee consider a 8 bit code?


Answer: minimize costs associated with data transmission

Question: Why did the committee decide on 7bit instead?


Answer: perforated tape at the time could record eight bits in one position

Question: What allowed for a parity bit for error chicking if needed?


Answer: ASA X3.4-1963

Context: With the other special characters and control codes filled in, ASCII was published as ASA X3.4-1963, leaving 28 code positions without any assigned meaning, reserved for future standardization, and one unassigned control code.:66, 245 There was some debate at the time whether there should be more control characters rather than the lowercase alphabet.:435 The indecision did not last long: during May 1963 the CCITT Working Party on the New Telegraph Alphabet proposed to assign lowercase characters to columns 6 and 7, and International Organization for Standardization TC 97 SC 2 voted during October to incorporate the change into its draft standard. The X3.2.4 task group voted its approval for the change to ASCII at its May 1963 meeting. Locating the lowercase letters in columns 6 and 7 caused the characters to differ in bit pattern from the upper case by a single bit, which simplified case-insensitive character matching and the construction of keyboards and printers.

Question: What was ASCII published as and when?


Answer: 28 code positions

Question: How many code positions were left unassigned for furture standardization?


Answer: May 1963

Question: When was the change to ASCII made official?


Answer: simplified case-insensitive character matching and the construction of keyboards and printers

Question: The lower case letters caused a differ in the patter, what did this cause?


Answer: ISO/IEC 646

Context: Other international standards bodies have ratified character encodings such as ISO/IEC 646 that are identical or nearly identical to ASCII, with extensions for characters outside the English alphabet and symbols used outside the United States, such as the symbol for the United Kingdom's pound sterling (£). Almost every country needed an adapted version of ASCII, since ASCII suited the needs of only the USA and a few other countries. For example, Canada had its own version that supported French characters. Other adapted encodings include ISCII (India), VISCII (Vietnam), and YUSCII (Yugoslavia). Although these encodings are sometimes referred to as ASCII, true ASCII is defined strictly only by the ANSI standard.

Question: What is a retified versionof ASCII?


Answer: extensions for characters outside the English alphabet and symbols used outside the United States

Question: What type of extensions do these other character encodings have?


Answer: ASCII suited the needs of only the USA and a few other countries

Question: Why did most countries need a adapted version of ASCII?


Answer: true ASCII is defined strictly only by the ANSI standard

Question: Why are the other versions of ASCII not true ASCII?


Answer: Teletype Model 33 ASR

Context: Probably the most influential single device on the interpretation of these characters was the Teletype Model 33 ASR, which was a printing terminal with an available paper tape reader/punch option. Paper tape was a very popular medium for long-term program storage until the 1980s, less costly and in some ways less fragile than magnetic tape. In particular, the Teletype Model 33 machine assignments for codes 17 (Control-Q, DC1, also known as XON), 19 (Control-S, DC3, also known as XOFF), and 127 (Delete) became de facto standards. The Model 33 was also notable for taking the description of Control-G (BEL, meaning audibly alert the operator) literally as the unit contained an actual bell which it rang when it received a BEL character. Because the keytop for the O key also showed a left-arrow symbol (from ASCII-1963, which had this character instead of underscore), a noncompliant use of code 15 (Control-O, Shift In) interpreted as "delete previous character" was also adopted by many early timesharing systems but eventually became neglected.

Question: What was the most influential device that interpretated the characters?


Answer: a printing terminal with an available paper tape reader/punch option

Question: What was the Teletype Model 33 ASR?


Answer: until the 1980s

Question: When was paper tape popular?


Answer: less costly and in some ways less fragile

Question: Why was paper tape better than magnetic tape?


Answer: code 15 (Control-O, Shift In)

Question: What code eventually became neglected?


Answer: The inherent ambiguity of many control characters, combined with their historical usage

Context: The inherent ambiguity of many control characters, combined with their historical usage, created problems when transferring "plain text" files between systems. The best example of this is the newline problem on various operating systems. Teletype machines required that a line of text be terminated with both "Carriage Return" (which moves the printhead to the beginning of the line) and "Line Feed" (which advances the paper one line without moving the printhead). The name "Carriage Return" comes from the fact that on a manual typewriter the carriage holding the paper moved while the position where the typebars struck the ribbon remained stationary. The entire carriage had to be pushed (returned) to the right in order to position the left margin of the paper for the next line.

Question: Why were problems created when transferring files between systems?


Answer: "Carriage Return" (which moves the printhead to the beginning of the line) and "Line Feed" (which advances the paper one line without moving the printhead)

Question: Teletype machines had to have two codes to termanate a line, what were they?


Answer: on a manual typewriter the carriage holding the paper moved while the position where the typebars struck the ribbon remained stationary

Question: Where does the name "Carriage Return" come from?


Answer: right

Question: What side does the carriage have to be pushed to when starting a new line?


Answer: 1878

Context: Many of the non-alphanumeric characters were positioned to correspond to their shifted position on typewriters; an important subtlety is that these were based on mechanical typewriters, not electric typewriters. Mechanical typewriters followed the standard set by the Remington No. 2 (1878), the first typewriter with a shift key, and the shifted values of 23456789- were "#$%_&'() – early typewriters omitted 0 and 1, using O (capital letter o) and l (lowercase letter L) instead, but 1! and 0) pairs became standard once 0 and 1 became common. Thus, in ASCII !"#$% were placed in second column, rows 1–5, corresponding to the digits 1–5 in the adjacent column. The parentheses could not correspond to 9 and 0, however, because the place corresponding to 0 was taken by the space character. This was accommodated by removing _ (underscore) from 6 and shifting the remaining characters left, which corresponded to many European typewriters that placed the parentheses with 8 and 9. This discrepancy from typewriters led to bit-paired keyboards, notably the Teletype Model 33, which used the left-shifted layout corresponding to ASCII, not to traditional mechanical typewriters. Electric typewriters, notably the more recently introduced IBM Selectric (1961), used a somewhat different layout that has become standard on computers—following the IBM PC (1981), especially Model M (1984)—and thus shift values for symbols on modern keyboards do not correspond as closely to the ASCII table as earlier keyboards did. The /? pair also dates to the No. 2, and the ,< .> pairs were used on some keyboards (others, including the No. 2, did not shift , (comma) or . (full stop) so they could be used in uppercase without unshifting). However, ASCII split the ;: pair (dating to No. 2), and rearranged mathematical symbols (varied conventions, commonly -* =+) to :* ;+ -=.

Question: When was the first typewritter with a shift key created?


Answer: using O (capital letter o) and l (lowercase letter L) instead

Question: What were used instead of 0 and 1?


Answer: which used the left-shifted layout corresponding to ASCII

Question: What layout did the Teletype Model 33 use?


Answer: do not correspond as closely

Question: Do shift values for symbols on modern keyboards correspond closely to the ASCII table?


Answer: delete

Context: Code 127 is officially named "delete" but the Teletype label was "rubout". Since the original standard did not give detailed interpretation for most control codes, interpretations of this code varied. The original Teletype meaning, and the intent of the standard, was to make it an ignored character, the same as NUL (all zeroes). This was useful specifically for paper tape, because punching the all-ones bit pattern on top of an existing mark would obliterate it. Tapes designed to be "hand edited" could even be produced with spaces of extra NULs (blank tape) so that a block of characters could be "rubbed out" and then replacements put into the empty space.

Question: What is the official name of code 127?


Answer: rubout

Question: What was code 127 labeled as for the Teletype?


Answer: to make it an ignored character

Question: Why did Teletype have the code for "rubout"?


Answer: introduces unnecessary complexity and questions as to how to interpret each character when encountered alone

Context: Unfortunately, requiring two characters to mark the end of a line introduces unnecessary complexity and questions as to how to interpret each character when encountered alone. To simplify matters plain text data streams, including files, on Multics used line feed (LF) alone as a line terminator. Unix and Unix-like systems, and Amiga systems, adopted this convention from Multics. The original Macintosh OS, Apple DOS, and ProDOS, on the other hand, used carriage return (CR) alone as a line terminator; however, since Apple replaced these operating systems with the Unix-based OS X operating system, they now use line feed (LF) as well.

Question: Why is adding two characters at the ned of a line problemsome?


Answer: line feed (LF) alone as a line terminator

Question: What id Multics use to simplify plain text data?


Answer: Macintosh OS, Apple DOS, and ProDOS

Question: What used carriage return(CR) alone as a line terminator?


Answer: Unix and Unix-like systems, and Amiga systems

Question: Who adopted this practice from Multics?


Answer: since Apple replaced these operating systems with the Unix-based OS X operating system

Question: When did Apple replace their CR with line feed (LF)?


Answer: the action of mastication (chewing)

Context: In the human digestive system, food enters the mouth and mechanical digestion of the food starts by the action of mastication (chewing), a form of mechanical digestion, and the wetting contact of saliva. Saliva, a liquid secreted by the salivary glands, contains salivary amylase, an enzyme which starts the digestion of starch in the food; the saliva also contains mucus, which lubricates the food, and hydrogen carbonate, which provides the ideal conditions of pH (alkaline) for amylase to work. After undergoing mastication and starch digestion, the food will be in the form of a small, round slurry mass called a bolus. It will then travel down the esophagus and into the stomach by the action of peristalsis. Gastric juice in the stomach starts protein digestion. Gastric juice mainly contains hydrochloric acid and pepsin. As these two chemicals may damage the stomach wall, mucus is secreted by the stomach, providing a slimy layer that acts as a shield against the damaging effects of the chemicals. At the same time protein digestion is occurring, mechanical mixing occurs by peristalsis, which is waves of muscular contractions that move along the stomach wall. This allows the mass of food to further mix with the digestive enzymes.

Question: What is the first step in the human digestive system?


Answer: a liquid secreted by the salivary glands

Question: What is saliva?


Answer: salivary amylase

Question: What is in saliva that starts to digest the starches?


Answer: a small, round slurry mass

Question: What is the definition of bolus?


Answer: peristalsis

Question: What is the action of the food morving down the esophagus into the stomach called?


Answer: eating specialised faeces in order to re-digest food

Context: Other animals, such as rabbits and rodents, practise coprophagia behaviours - eating specialised faeces in order to re-digest food, especially in the case of roughage. Capybara, rabbits, hamsters and other related species do not have a complex digestive system as do, for example, ruminants. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft faecal pellets of partially digested food are excreted and generally consumed immediately. They also produce normal droppings, which are not eaten.

Question: What is the practive of coprophagia behaviours?


Answer: extract more nutrition

Question: Why do some animals pass food through their gut twice?


Answer: excreted and generally consumed immediately

Question: What happens with these soft feacal pellets?


Answer: not eaten

Question: Are normal droppings also eaten?