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The products of photosynthesis are glucose and what else?

nitrogen

carbon

hydrogen

oxygen

The products of photosynthesis are glucose and oxygen.

In what way do bacteria reproduce?

cellular respiration

sexual reproduction

fragmentation

binary fission

Bacteria reproduce by binary fission, resulting in two daughter cells identical to the parent cell.

What type of fibers are made mostly of protein in living things?

connective tissue fibers

organ fibers

liver fibers

muscle fibers

Muscle fibers are made mostly of protein.

What force is responsible for erosion by flowing water and glaciers?

weight

kinetic

electromagnetic

gravity

Gravity is responsible for erosion by flowing water and glaciers. That’s because gravity pulls water and ice downhill. These are ways gravity causes erosion indirectly. But gravity also causes erosion directly. Gravity can pull soil, mud, and rocks down cliffs and hillsides. This type of erosion and deposition is called mass wasting . It may happen suddenly. Or it may occur very slowly, over many years.

Nearly all protists exist in some type of aquatic environment, including freshwater and marine environments, damp soil, and even snow. several protist species are parasites that infect animals or plants. a few protist species live on dead organisms or their wastes, and contribute to what?

spontaneous mutation

greenhouse gas

habitat loss

their decay

Habitats Nearly all protists exist in some type of aquatic environment, including freshwater and marine environments, damp soil, and even snow. Several protist species are parasites that infect animals or plants. A few protist species live on dead organisms or their wastes, and contribute to their decay.

What type of rocks form from cooled magma or lava?

metamorphic

granite

sedementary

igneous

Igneous rocks form from cooled magma or lava.

What kind of cells have positive cell potentials, and all the reduction reactions are reversible?

neutral cells

new cells

inhibited cells

galvanic cells

Galvanic cells have positive cell potentials, and all the reduction reactions are reversible. The reaction at the anode will be the half-reaction with the smaller or more negative standard reduction potential. Reversing the reaction at the anode (to show the oxidation) but not its standard reduction potential gives: Anode (oxidation):.

A fish's stream-lined body that reduces water resistance is an example of what kind of response to an aquatic lifestyle?

evolution

natural selection

retraction

adaptation

Many structures in fish are adaptations for their aquatic lifestyle. For example, fish have a stream-lined body that reduces water resistance while swimming.

Emissions of what gas into the atmosphere from fossil fuel burning have been rising for the past several decades?

neon

sulphur

oxygen

carbon dioxide

Carbon dioxide emissions into the atmosphere from fossil fuel burning have been rising for the past several decades.

Gymnosperms have seeds but do not have what?

roots

leaves

stems

flowers

Gymnosperms have seeds but do not have flowers.

Modern members of what broad animal group live in many different habitats and are found on every continent except antarctica?

parasites

arachnids

amphibians

reptiles

Modern reptiles live in many different habitats. They can be found on every continent except Antarctica.

The right ventricle pumps what type of blood toward the lungs?

oxygen-rich

plasma

oxygenated

oxygen-poor

The right ventricle pumps oxygen-poor blood toward the lungs, where it receives oxygen.

Some 96% of the dry mass consists of organic compounds produced by what?

reproduction

erosion

electrolysis

photosynthesis

What is it called when something is unable to move from place to place?

ovate

Undrate

obovate

sessile

Sponges come in a variety of shapes and sizes. For example, they may be shaped like tubes, fans, cones, or just blobs. They range in diameter from about a centimeter (0.4 inches) to over a meter (3.3 feet). Many species live in colonies that may be quite large. Adult sponges are sessile . This means they are unable to move from place to place. Root-like projections anchor them to solid surfaces such as rocks and reefs.

What waves are the broad range of electromagnetic waves with the longest wavelengths and lowest frequencies?

light

sound

microwaves

radio

Radio waves are the broad range of electromagnetic waves with the longest wavelengths and lowest frequencies. They are used for radio and television broadcasts, microwave ovens, cell phone transmissions, and radar.

What are the two main types of sedimentary rocks?

basalt and dolomite

sandstone and shale

shale and limestone

clastic and chemical

There are two main types of sedimentary rocks: clastic and chemical. Clastic rocks are made of sediments, which are sometimes called clasts. Creating rocks from sediments is called lithification . Chemicals precipitate from liquid to form chemical sedimentary rocks.

Light waves which interfere with themselves after interaction with a small aperture or target are said to what?

reflect

refract

adduce

diffract

Waves are characterized by their ability to constructively and destructively interfere . Light waves which interfere with themselves after interaction with a small aperture or target are said to diffract .

Distance traveled divided by time yields what measurement, which is another word used to describe the speed of a chemical reaction?

acceleration

flow

displacement

rate

Chemists need to be concerned with the rates at which chemical reactions occur. Rate is another word for speed. If a sprinter takes 11.0 s to run a 100 m dash, his rate or speed is given by the distance traveled divided by the time.

Beryllium, magnesium, calcium, strontium, and barium are classified as what type of metals?

alkaline support metals

alkaline aligned metals

acid earth metals

alkaline earth metals

The alkaline earth metals include beryllium, magnesium, calcium, strontium, and barium. Strontium and barium react with air and must be stored in oil.

Common among mammals and insects, pheromones are often related to what type of behavior?

cardiac

aggressive

immune

reproductive

Neutron stars are the corpses of left over what?

stellar explosions

planet explosions

gravitational explosions

supernova explosions

Neutron stars are the corpses of stars left over after supernova explosions. They are the size of a small city, but can spin several times per second. (Try to imagine this in your head. ) Consider a neutron star of radius 10 km that spins with a period of 0.8 seconds. Imagine a person is standing at the equator of this neutron star. Calculate the centripetal acceleration of this person and compare it to the acceleration due to gravity on Earth.

In recent years, however, researchers have discovered that microsporidia actually have tiny organelles derived from what?

plasma

proteins

carbohydrates

mitochondria

The negative logarithm of the hydroxide-ion concentration of a solution is called?

the piel

the hil

the hop

the poh

As with the hydrogen-ion concentration, the concentration of the hydroxide ion can be expressed logarithmically by the pOH. The pOH of a solution is the negative logarithm of the hydroxide-ion concentration.

What is the greatest contribution of arthropods to human food supply?

hibernation

vegetation

reproduction

pollination

The intentional cultivation of arthropods and other small animals for human food, referred to as minilivestock, is now emerging in animal husbandry as an ecologically sound concept. However, the greatest contribution of arthropods to human food supply is by pollination. Three-fourths of the world’s flowering plants and about 35% of the world’s food crops depend on animal pollinators to reproduce and increase crop yields. More than 3,500 species of native bees pollinate crops. Some scientists estimate that one out of every three bites of food we eat exists because of animal pollinators, including birds and bats and arthropods like bees, butterflies and moths, and beetles and other insects.

What kind of weather change do la nina years usually bring?

moisture

heat

Mass amounts of snow

drought

El Niño and La Niña bring about dramatic changes in climate for a year or two. In some locations, one brings rain and the other brings drought. In California, for example, El Niño years are full of snow and rain. La Niña years tend toward drought. These variations can bring tremendous changes to living creatures. Humans are also affected; for example, erosion from storms may be very high some years.

In physics, _______ is defined as the average kinetic energy of the particles in an object?

heat

climate

potential energy

temperature

No doubt you already have a good idea of what temperature is. You might define it as how hot or cold something feels. In physics, temperature is defined as the average kinetic energy of the particles in an object. When particles move more quickly, temperature is higher and an object feels warmer. When particles move more slowly, temperature is lower and an object feels cooler.

What are proteins encoded by?

codons

DNA

RNA

genes

In alcoholic fermentation , which acid changes to alcohol and carbon dioxide?

lipoic

rain

chloride

pyruvic

In alcoholic fermentation , pyruvic acid changes to alcohol and carbon dioxide. This is shown in Figure below . NAD + also forms from NADH, allowing glycolysis to continue making ATP. This type of fermentation is carried out by yeasts and some bacteria. It is used to make bread, wine, and biofuels.

What is another term for scale worms?

spirogyra

trichina

wormidanopis

halkieria

Halkieria, or scale worms, are an example of a fossil life from the Cambrian.

What type of device do scientist use to determine wind speed?

dynamometer

barometer

photometer

anemometer

Which constellation looks like a rectangle high in winter's south-southeastern sky?

Andromeda

Caelum

Apus

orion

The star constellation “Orion, The Hunter”. Orion is one of the most beautiful of all constellations, and one of the easiest to find. It looks like a large (slightly twisted) rectangle high in winter's south-southeastern sky. Two of the brightest stars in the evening sky lie at opposite corners of the rectangle: bright orange-red Betelgeuse at the northeastern corner (upper left in the photo) and even brighter Rigel at the southwest (lower right in the photo). Betelgeuse is at least 300 times the Sun's diameter, and perhaps much more. It puts out about 100,000 times more energy than the Sun does. When Betelgeuse dies, it will create a fireball that will briefly outshine billions of normal stars. Betelgeuse is a red giant and Rigel is a blue giant.

What mammal is often a pollinator of nocturnal flowers?

rabbits

sunbirds

hummingbirds

bat

Pollination by Bats In the tropics and deserts, bats are often the pollinators of nocturnal flowers such as agave, guava, and morning glory. The flowers are usually large and white or pale-colored; thus, they can be distinguished from the dark surroundings at night. The flowers have a strong, fruity, or musky fragrance and produce large amounts of nectar. They are naturally large and wide-mouthed to accommodate the head of the bat. As the bats seek the nectar, their faces and heads become covered with pollen, which is then transferred to the next flower.

What can reproduce by infecting the cell of a living host?

carcinogens

bacteria

mucus

virus

A virus cannot reproduce on its own. However, a virus can reproduce by infecting the cell of a living host. Inside the host cell, the virus uses the cell’s structures, materials, and energy to make copies of itself.

The theory that establishes the concepts of atoms and how they compose matter is called what?

contemporary atomic theory

modern particle theory

unified matter theory

modern atomic theory

The modern atomic theory establishes the concepts of atoms and how they compose matter.

How does the heart transport blood?

muscles

blood pellets

nerves

blood vessels

A screw is an inclined plane wrapped around a cylinder. When on a screw, inclined planes are called threads, which can be seen in the image above. The mechanical advantage of a screw increases with the density of the threads. The calculations to determine the IMA for a screw involve the circumference of the head of the screw and the thread width. When the screw is turned completely around one time, the screw penetrates by one thread width. So, if the circumference of the head of a screw is 3.0 cm and the thread width is 0.60 cm, then the IMA would be calculated by.

The gender of a baby is determined by what special pair of chromosomes?

reflection chromosomes

diploid chromosomes

sister chromatids

sex chromosomes

One of the exciting things about expecting a child is wondering if the baby will be a boy or a girl. There are many superstitions about how one might influence or predict the outcome. But what really determines if a baby is male or female? We now know that the gender of a baby is determined by a special pair of chromosomes known as the sex chromosomes.

What does the activity of an organism depend on the totality of?

chemical attraction

interdependence

adaptations

independent cells

the activity of an organism depends on the total activity of independent cells,.

What is solid water that forms when water vapor undergoes deposition?

dew

distillate

glacier

frost

Frost is solid water that forms when water vapor undergoes deposition.

What gets released into the atmosphere when fossil fuels are burned?

chemical dioxide

oxygen

hydrogen

carbon dioxide

Using fossil fuels and nuclear energy creates other problems as well. The burning of fossil fuels releases carbon dioxide into the atmosphere. This is one of the major greenhouse gases causing global climate change. Nuclear power creates another set of problems, including the disposal of radioactive waste.

What is the term for the measure of a fluid's thickness?

salinity

friction

elasticity

viscosity

Characteristics of Blood When you think about blood, the first characteristic that probably comes to mind is its color. Blood that has just taken up oxygen in the lungs is bright red, and blood that has released oxygen in the tissues is a more dusky red. This is because hemoglobin is a pigment that changes color, depending upon the degree of oxygen saturation. Blood is viscous and somewhat sticky to the touch. It has a viscosity approximately five times greater than water. Viscosity is a measure of a fluid’s thickness or resistance to flow, and is influenced by the presence of the plasma proteins and formed elements within the blood. The viscosity of blood has a dramatic impact on blood pressure and flow. Consider the difference in flow between water and honey. The more viscous honey would demonstrate a greater resistance to flow than the less viscous water. The same principle applies to blood. The normal temperature of blood is slightly higher than normal body temperature—about 38 °C (or 100.4 °F), compared to 37 °C (or 98.6 °F) for an internal body temperature reading, although daily variations of 0.5 °C are normal. Although.

Plant cells have structures that animal cells?

eat

have

drink

lack

Plant cells have structures that animal cells lack. What important process takes place in plant cells but not in animal cells that might explain their differences?.

What reduces the need for pesticides and other toxic chemicals?

yeast

pollen

helium

fungi

Harmless fungi can be used to control pathogenic bacteria and insect pasts on crops. Fungi compete with bacteria for nutrients and space, and they parasitize insects that eat plants. Fungi reduce the need for pesticides and other toxic chemicals.

Matter can be described with what two encompassing types of properties?

color and distance

velocity and energy

thermal and magnetic

physical and chemical

Matter can be described with both physical properties and chemical properties.

When the number of active receptors falls below that threshold, what happens to the cellular response?

it stabilizes

it responds

it increases

it ceases

Types of neurons include sensory neurons, motor neurons, and?

synapses

histones

anions

interneurons

Types of neurons include sensory neurons, motor neurons, and interneurons.

Active and passive forms of what enable the body to resist damage from pathogens?

autonomy

potential

stem cells

immunity

Active versus Passive Immunity Immunity to pathogens, and the ability to control pathogen growth so that damage to the tissues of the body is limited, can be acquired by (1) the active development of an immune response in the infected individual or (2) the passive transfer of immune components from an immune individual to a nonimmune one. Both active and passive immunity have examples in the natural world and as part of medicine. Active immunity is the resistance to pathogens acquired during an adaptive immune response within an individual (Table 21.6). Naturally acquired active immunity, the response to a pathogen, is the focus of this chapter. Artificially acquired active immunity involves the use of vaccines. A vaccine is a killed or weakened pathogen or its components that, when administered to a healthy individual, leads to the development of immunological memory (a weakened primary immune response) without causing much in the way of symptoms. Thus, with the use of vaccines, one can avoid the damage from disease that results from the first exposure to the pathogen, yet reap the benefits of protection from immunological memory. The advent of vaccines was one of the major medical advances of the twentieth century and led to the eradication of smallpox and the control of many infectious diseases, including polio, measles, and whooping cough.

What is the energy of motion called?

mixed energy

binary energy

potential energy

kinetic energy

What is the term for an infection caused by a fungal parasite?

acrobasis

mydriasis

mitosis

mycosis

What do you call the ability to sense sound energy and perceive sound?

echolocation

tuning

sensory deprivation

hearing

Hearing is the ability to sense sound energy and perceive sound. The ear is the organ that senses sound and allows us to hear. Damage to structures of the ear may cause hearing loss. Total hearing loss is called deafness.

Some plants can detect increased levels of what when reflected from leaves of encroaching neighbors?

air

water

oxygen

light

What are the high points of a transverse wave called?

ridges

peaks

troughs

crests

A transverse wave can be characterized by the high and low points reached by particles of the medium as the wave passes through. This is illustrated in Figure below . The high points are called crests, and the low points are called troughs.

What is the transfer of heat by a current?

diffusion

radiation

combustion

convection

Convection is the transfer of heat by a current. Convection happens in a liquid or a gas. Air near the ground is warmed by heat radiating from Earth's surface. The warm air is less dense, so it rises. As it rises, it cools. The cool air is dense, so it sinks to the surface. This creates a convection current, like the one in Figure below . Convection is the most important way that heat travels in the atmosphere.

When acellular slime molds swarm, they fuse together to form a single cell with many what?

lungs

digestive tracts

cytoplasm

nuclei

When acellular slime molds swarm, they fuse together to form a single cell with many nuclei.

Potential energy is not only associated with the location of matter, but also with the structure of matter. even a spring on the ground has potential energy if it is what?

coupled

ignored

watched

compressed

Potential energy is not only associated with the location of matter, but also with the structure of matter. Even a spring on the ground has potential energy if it is compressed; so does a rubber band that is pulled taut. On a molecular level, the bonds that hold the atoms of molecules together exist in a particular structure that has potential energy. Remember that anabolic cellular pathways require energy to synthesize complex molecules from simpler ones and catabolic pathways release energy when complex molecules are broken down. The fact that energy can be released by the breakdown of certain chemical bonds implies that those bonds have potential energy. In fact, there is potential energy stored within the bonds of all the food molecules we eat, which is eventually harnessed for use. This is because these bonds can release energy when broken. The type of potential energy that exists within chemical bonds, and is released when those bonds are broken, is called chemical energy. Chemical energy is responsible for providing living cells with energy from food. The release of energy occurs when the molecular bonds within food molecules are broken.

What is the name of film that polyester fibers form?

Softness

layers

fabric

mylar

Polyester molecules make excellent fibers and are used in many fabrics. A knitted polyester tube, which is biologically inert, can be used in surgery to repair or replace diseased sections of blood vessels. PET is used to make bottles for soda pop and other beverages. It is also formed into films called Mylar. When magnetically coated, Mylar tape is used in audio- and videocassettes. Synthetic arteries can be made from PET, polytetrafluoroethylene, and other polymers.

Where do germline mutations occur in?

In blood cells

in aggregations

in spores

in gametes

Germline mutations occur in gametes. Somatic mutations occur in other body cells. Chromosomal alterations are mutations that change chromosome structure. Point mutations change a single nucleotide. Frameshift mutations are additions or deletions of nucleotides that cause a shift in the reading frame.

What a mixture of nitric acid and hydrochloric acid?

sulfate regia

crystal regia

acidus regia

aqua regia

Aqua regia, a mixture of nitric acid and hydrochloric acid, is one of the few materials that will dissolve gold. This material, translated to "royal water" in English, was named so because it could dissolve the royal metal gold. First noted in the fourteenth century, aqua regia could be used to help ascertain whether a particular material was actually gold or was some trickery of the alchemist. Nitric acid by itself will not dissolve gold, but will in combination with hydrochloric acid. The chemistry of the process is rather complex, with both acids reacting with the metal to form soluble gold compounds. The gold can be recovered from the solution, making the process useful for purification purposes.

Most members of what kingdom of spore-making organisms grow on the forest floor, where the dark and damp environment is rich?

bacteria

algae

moss

fungi

Habitats Although fungi are primarily associated with humid and cool environments that provide a supply of organic matter, they colonize a surprising diversity of habitats, from seawater to human skin and mucous membranes. Chytrids are found primarily in aquatic environments. Other fungi, such as Coccidioides immitis, which causes pneumonia when its spores are inhaled, thrive in the dry and sandy soil of the southwestern United States. Fungi that parasitize coral reefs live in the ocean. However, most members of the Kingdom Fungi grow on the forest floor, where the dark and damp environment is rich.

What results when the water vapor from a hot shower contacts the cooler surface of a mirror?

cleaner mirror

the mirror breaks

mirror brightens

foggy mirror

If you take a hot shower in a closed bathroom, the mirror is likely to "fog" up. The "fog" consists of tiny droplets of water that form on the cool surface of the mirror. Why does this happen? Some of the hot water from the shower evaporates, so the air in the bathroom contains a lot of water vapor. When the water vapor contacts cooler surfaces, such as the mirror, it cools and loses energy. The cooler water particles no longer have enough energy to overcome the forces of attraction between them. They come together and form droplets of liquid water.

What type of vascular plants produce seeds in cones?

lipids

Proteins

angiosperms

gymnosperms

Gymnosperms are vascular plants that produce seeds in cones . Examples include conifers such as pine and spruce trees. The gymnosperm life cycle has a dominant sporophyte generation. Both gametophytes and the next generation’s new sporophytes develop on the sporophyte parent plant. Figure below is a diagram of a gymnosperm life cycle.

In fruit flies, all homeotic genes are found on one what?

site

genome

enzymes

chromosome

Certain medications can suppress the immune system. this is an intended effect of drugs given to people with what?

genetic disorders

benign tumors

infections

transplanted organs

Certain medications can suppress the immune system. This is an intended effect of drugs given to people with transplanted organs. In many cases, however, it is an unwanted side effect of drugs used to treat other diseases.

The geometry of the bf 3 molecule is called what?

distorted planar

fractal planar

spherical planar

trigonal planar

The geometry of the BF 3 molecule is called trigonal planar . The fluorine atoms are positioned at the vertices of an equilateral triangle. The F-B-F angle is 120°, and all four atoms lie in the same plane.

In multicellular organisms, mutations can be subdivided into germline mutations and?

resultant mutations

elective mutations

comparative mutations

somatic mutations

Once again, a mutation is the change in the DNA or RNA sequence. In multicellular organisms, mutations can be subdivided into germline mutations and somatic mutations. Germline mutations occur in the DNA of sex cells, or gametes, and are therefore potentially very serious. These mutations can be passed to the next generation. If the zygote contains the mutation, every cell in the resulting organism will have that mutation. If the mutation results in a disease phenotype, the mutation causes what is called a hereditary disease. Somatic mutations , which occur in somatic, or body, cells, cannot be passed to the next generation (offspring). Mutations present in a somatic cell of an organism will be present (by DNA replication and mitosis) in all descendants of that cell. If the mutation is present in a gene that is not used in that cell type, the mutation may have no effect. On the other hand, the mutation may lead to a serious medical condition such as cancer.

What is the name for a biologist who studies fungi?

oncologists

egyptologists

musicologists

mycologists

Mycologist Mycologists are biologists who study fungi. Mycology is a branch of microbiology, and many mycologists start their careers with a degree in microbiology. To become a mycologist, a bachelor's degree in a biological science (preferably majoring in microbiology) and a master's degree in mycology are minimally necessary. Mycologists can specialize in taxonomy and fungal genomics, molecular and cellular biology, plant pathology, biotechnology, or biochemistry. Some medical microbiologists concentrate on the study of infectious diseases caused by fungi (mycoses). Mycologists collaborate with zoologists and plant pathologists to identify and control difficult fungal infections, such as the devastating chestnut blight, the mysterious decline in frog populations in many areas of the world, or the deadly epidemic called white nose syndrome, which is decimating bats in the Eastern United States. Government agencies hire mycologists as research scientists and technicians to monitor the health of crops, national parks, and national forests. Mycologists are also employed in the private sector by companies that develop chemical and biological control products or new agricultural products, and by companies that provide disease control services. Because of the key role played by fungi in the fermentation of alcohol and the preparation of many important foods, scientists with a good understanding of fungal physiology routinely work in the food technology industry. Oenology, the science of wine making, relies not only on the knowledge of grape varietals and soil composition, but also on a solid understanding of the characteristics of the wild yeasts that thrive in different wine-making regions. It is possible to purchase yeast strains isolated from specific grape-growing regions. The great French chemist and microbiologist, Louis Pasteur, made many of his essential discoveries working on the humble brewer’s yeast, thus discovering the process of fermentation.

How many different kinds of ions are produced when sodium chloride dissociates ?

three

five

one

two

The sodium chloride dissociates into two ions, while the glucose does not dissociate. Therefore, equal concentrations of each solution will result in twice as many dissolved particles in the case of the sodium chloride. The vapor pressure of the sodium chloride solution will be lowered twice the amount as the glucose solution.

What mineral is made of one silicon atom and two oxygen atoms?

cobalt

glass

pumice

quartz

5. Quartz is made of one silicon atom and two oxygen atoms. If you find a mineral and find that it is made of one silicon atom and one oxygen atom is it quartz?.

How many cycles do cells have?

seven

six

two

four

This diagram represents the cell cycle in eukaryotes. The cell cycle depicts the life of an eukaryotic cell. The cell cycle has four phases: the first growth or gap (G 1 ) phase, the synthesis (S) phase, the second growth or gap (G 2 ) phase and the mitotic (M) phase. The M phase includes mitosis and cytokinesis. The cell spends the majority of the cycle in the first three phases (G 1 , S, G 2 ) of the cycle, collectively known as interphase. After cytokinesis, two genetically identical daughter cells are formed.

Gas particles can move randomly in what directions?

some directions

one direction

few directions

all directions

Christopher Auyeung. Gas particles move randomly in all directions . CC BY-NC 3.0.

The total number of protons and neutorns in an atom is called what?

formation number

atom number

volume number

mass number

The mass number is defined as the total number of protons and neutrons in an atom.

All matter is composed of tiny indivisible particles called atoms. all atoms of an element are identical in mass and this?

electrical properties

acid properties

liquid properties

chemical properties

All matter is composed of tiny indivisible particles called atoms. All atoms of an element are identical in mass and chemical properties, whereas atoms of different elements differ in mass and fundamental chemical properties. A chemical compound is a substance that always contains the same atoms in the same ratio. In chemical reactions, atoms from one or more compounds or elements redistribute or rearrange in relation to other atoms to form one or more new compounds. Atoms themselves do not undergo a change of identity in chemical reactions. This last hypothesis suggested that the alchemists’ goal of transmuting other elements to gold was impossible, at least through chemical reactions. We now know that Dalton’s atomic theory is essentially correct, with four minor modifications:.

Where do lightnings build up?

troposphere

stratosphere

air

clouds

Lightning is the discharge of static electricity that has built up on clouds. Every year, the earth experiences an average of 25 million lightning strikes. Lightning bolts travel at speeds up to 60,000 miles per second, and can reach temperatures of 50,000°F, which is five times the temperature of the surface of the sun. The energy contained in a single lightning strike could light a 100 Watt light bulb 24 hours per day for 90 days.

What do we call zeros that appear after nonzero digits?

placeholders

left-end zeros

significant digits

right-end zeros

4. Zeros that appear after all nonzero digits are called right-end zeros. Right-end zeros in a number that lacks a decimal point are not significant. A. 140 has two significant figures.

What term is used to describe a bond formed by the overlap of orbitals in an end-to-end fashion, with the electron density concentrated between the nuclei of the bonding atoms?

rna bond

beta bond

lattice bond

sigma bond

It is necessary to distinguish between the two types of covalent bonds in a C 2 H 4 molecule. A sigma bond (σ bond) is a bond formed by the overlap of orbitals in an end-to-end fashion, with the electron density concentrated between the nuclei of the bonding atoms. A pi bond (π bond) is a bond formed by the overlap of orbitals in a side-by-side fashion, with the electron density concentrated above and below the plane of the nuclei of the bonding atoms. Figure below shows the two types of bonding in C 2 H 4 . The sp 2 hybrid orbitals are orange and the p z orbital is green. Three sigma bonds are formed by each carbon atom with its hybrid orbitals. The pi bond is the “second” bond of the double bond between the carbon atoms and is shown as an elongated blue lobe that extends both above and below the plane of the molecule, which contains the six atoms and all of the sigma bonds.

According to count rumford, which two are equivalent ways of transferring energy?

time and space

addition and multiplication

osmosis and heredity

heat and work

In the 1780s, an American scientist named Benjamin Thompson, also known as Count Rumford, was hired by the Elector of Bavaria to supervise the manufacture of cannons. During the manufacturing process, teams of horses harnessed to a large-toothed wheel supplied the power needed to drill a hole several inches in diameter straight down the center of a solid brass or bronze cylinder, which was cooled by water. Based on his observations, Rumford became convinced that heat and work are equivalent ways of transferring energy.

What type of radio waves exist in the 540 to 1600 khz frequency range?

fm radio waves

microwaves

sound waves

am radio waves

AM radio waves are used to carry commercial radio signals in the frequency range from 540 to 1600 kHz. The abbreviation AM stands for amplitude modulation, which is the method for placing information on these waves. (See Figure 24.12. ) A carrier wave having the basic frequency of the radio station, say 1530 kHz, is varied or modulated in amplitude by an audio signal. The resulting wave has a constant frequency, but a varying amplitude. A radio receiver tuned to have the same resonant frequency as the carrier wave can pick up the signal, while rejecting the many other frequencies impinging on its antenna. The receiver’s circuitry is designed to respond to variations in amplitude of the carrier wave to replicate the original audio signal. That audio signal is amplified to drive a speaker or perhaps to be recorded.

What type of cells make up about one quarter of all white blood cells?

tumors

Fat

erythrocytes

lymphocytes

Lymphocytes ( Figure below ), a type of white blood cell, are the key cells of an immune response. There are trillions of lymphocytes in the human body. They make up about one quarter of all white blood cells. Usually, fewer than half of the body’s lymphocytes are in the blood. The rest are in the lymph, lymph nodes, and lymph organs.

The mass of the objects and the distance between them affect the strength of what universal force?

motion

states of matter

weight

gravity

All objects in the universe have a gravitational attraction to each other ( Figure below ). The strength of the force of gravity depends on two things. They are the mass of the objects and the distance between them. The greater the objects’ mass, the greater the force of attraction. As the distance between the objects increases, the force of attraction decreases.

Without the dominant disturbance, the fire-adapted species are usually outcompeted and biodiversity is what?

increased

immaterial

unaffected

reduced

Constantly going through some form of growth and repair is a characteristic of all what?

mass

viruses

bacteria

living things

Positive charges move in the direction of the electric field and the same direction as what current?

relativity current

alternating current

direct current

conventional current

Figure 20.4 Current I is the rate at which charge moves through an area A , such as the cross-section of a wire. Conventional current is defined to move in the direction of the electric field. (a) Positive charges move in the direction of the electric field and the same direction as conventional current. (b) Negative charges move in the direction opposite to the electric field. Conventional current is in the direction opposite to the movement of negative charge. The flow of electrons is sometimes referred to as electronic flow.

Redox reactions, like other chemical reactions, begin with a product and end with what?

stimulant

plasma

decomposition

reactant

Learn to balanced simple redox reactions by inspection. Learn to balance complex redox reactions by the half reaction method. Use the solvent, or parts of it, as a reactant or a product in balancing a redox reaction. Balancing simple redox reactions can be a straightforward matter of going back and forth between products and reactants. For example, in the redox reaction of Na and Cl2:.

How does alcohol expand over a wide range of temperatures?

erratically

variably

exponentially

uniformly

The red liquid in this thermometer is alcohol. Alcohol expands uniformly over a wide range of temperatures. This makes it ideal for use in thermometers.

How many years ago may the earliest fungi have evolved?

.250 million

.350 million

500 million

600 million

The earliest fungi may have evolved about 600 million years ago.

What are the bones in partly movable joints held in place by?

collagen

socket

tendons

cartilage

Partly movable joints allow only very limited movement. Bones at these joints are held in place by cartilage. The ribs and sternum are connected by partly movable joints.

Sepals, petals, stamens, and carpels are what kind of organs?

marine

animal

reproductive

floral

How do most growing plant cells expand?

through photosynthesis

through germination

through cell respiration

through water uptake

What is the common term for the chemical formula h 2 0?

oxygen

hydrogen

air

water

Water is an amazing molecule. It has a very simple chemical formula, H 2 O. It is made of just two hydrogen atoms bonded to one oxygen atom. Water is remarkable in terms of all the things it can do. Lots of things dissolve easily in water. Some types of rock can even completely dissolve in water! Other minerals change by adding water into their structure.

What kind of reaction is needed to prepare amides?

lipophilic acid reaction

amino acid reaction

oxidize acid reaction

carboxylic acid reaction

Amides are prepared by the reaction of a carboxylic acid with ammonia or an amine.

What is the process by which the egg is fertilized by the pollen of the same flower?

self condensation

self formation

self realization

self pollination

In self-pollination , the egg is fertilized by the pollen of the same flower.

In moss, what becomes elongated to elevate the capsule to enhance spore dispersal?

porta

sera

risa

seta

What is the base unit that frequency is typically measured in?

degrees

watt

volume

hertz

The frequency , , is the number of cycles an object goes through in 1 second. Frequency is measured in Hertz (Hz). 1 Hz = 1 cycle per sec.

Controlling muscles and maintaining balance are just two of the roles of what system?

bacterial system

electrical system

digestive system

nervous system

Controlling muscles and maintaining balance are just two of the roles of the nervous system. The nervous system also lets you:.

Displacement divided by time is equal to the average what?

acceleration

force

speed

velocity

Average velocity is displacement divided by time.

The complete hydrolysis of starch yields what?

sucrose

glutamate

insulin

glucose

Both amylopectin and glycogen contain branch points that are linked through α-1,6linkages. These branch points occur more often in glycogen. Dextrins are glucose polysaccharides of intermediate size. The shine and stiffness imparted to clothing by starch are due to the presence of dextrins formed when clothing is ironed. Because of their characteristic stickiness with wetting, dextrins are used as adhesives on stamps, envelopes, and labels; as binders to hold pills and tablets together; and as pastes. Dextrins are more easily digested than starch and are therefore used extensively in the commercial preparation of infant foods. The complete hydrolysis of starch yields, in successive stages, glucose:.

What term describes an imbalance of attractive forces between liquid molecules at the surface of a liquid?

obsolute tension

currents tension

molecular tension

surface tension

Surface tension is an imbalance of attractive forces between liquid molecules at the surface of a liquid.

In mammals, four specialized types of what serve to cut, tear, and grind food?

spines

scales

plates

teeth

Mammalian teeth are also important for digestion. The four types of teeth are specialized for different feeding functions, as shown in Figure below . Together, the four types of teeth can cut, tear, and grind food. This makes food easier and quicker to digest.

Atherosclerosis and coronary heart disease are examples of what type of body system disease?

excretory system

connective system

digestive system

cardiovascular system

Diseases of the cardiovascular system are common and may be life threatening. Examples include atherosclerosis and coronary heart disease. A healthy lifestyle can reduce the risk of such diseases developing. This includes avoiding smoking, getting regular physical activity, and maintaining a healthy percent of body fat.

When cats mark their territory by rubbing their face against an object, they deposit chemicals released by what structures?

taste buds

whiskers

pituitary glands

scent glands

Some animals deposit chemicals to mark the boundary of their territory. This is why dogs urinate on fire hydrants and other objects. Cats may also mark their territory by depositing chemicals. They have scent glands in their face. They deposit chemicals by rubbing their face against objects.

Like other bryophytes, moss plants spend most of their life cycle as?

bacteriophages

spores

copepods

gametophytes

Like other bryophytes, moss plants spend most of their life cycle as gametophytes. Find the sporophyte in the diagram. Do you see how it is growing on the gametophyte plant?.