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What is the term for a random change in allele frequencies that occurs in a small population? | mutation | evolution | speciation | genetic drift | Genetic drift is a random change in allele frequencies that occurs in a small population. When a small number of parents produce just a few offspring, allele frequencies in the offspring may differ, by chance, from allele frequencies in the parents. |
Aerobic exercise helps improve the cardiovascular system, while what exercise causes muscles to get bigger and stronger? | enzymatic | endurance | skeletal | anaerobic | Aerobic exercise helps improve the cardiovascular system, while anaerobic exercise causes muscles to get bigger and stronger. |
An excessive posterior curvature of the thoracic region is also known as what? | osmosis | lordosis | babesiosis | kyphosis | Vertebral Column Developmental anomalies, pathological changes, or obesity can enhance the normal vertebral column curves, resulting in the development of abnormal or excessive curvatures (Figure 7.21). Kyphosis, also referred to as humpback or hunchback, is an excessive posterior curvature of the thoracic region. This can develop when osteoporosis causes weakening and erosion of the anterior portions of the upper thoracic vertebrae, resulting in their gradual collapse (Figure 7.22). Lordosis, or swayback, is an excessive anterior curvature of the lumbar region and is most commonly associated with obesity or late pregnancy. The accumulation of body weight in the abdominal region results an anterior shift in the line of gravity that carries the weight of the body. This causes in an anterior tilt of the pelvis and a pronounced enhancement of the lumbar curve. Scoliosis is an abnormal, lateral curvature, accompanied by twisting of the vertebral column. Compensatory curves may also develop in other areas of the vertebral column to help maintain the head positioned over the feet. Scoliosis is the most common vertebral abnormality among girls. The cause is usually unknown, but it may result from weakness of the back muscles, defects such as differential growth rates in the right and left sides of the vertebral column, or differences in the length of the lower limbs. When present, scoliosis tends to get worse during adolescent growth spurts. Although most individuals do not require treatment, a back brace may be recommended for growing children. In extreme cases, surgery may be required. Excessive vertebral curves can be identified while an individual stands in the anatomical position. Observe the vertebral profile from the side and then from behind to check for kyphosis or lordosis. Then have the person bend forward. If scoliosis is present, an individual will have difficulty in bending directly forward, and the right and left sides of the back will not be level with each other in the bent position. |
What are the two main divisions of the human nervous system? | left and right | somatic and autonomic | central and identical | central and peripheral | The two main divisions of the human nervous system are the central nervous system and the peripheral nervous system. The peripheral nervous system has additional divisions. |
What is composed of two strands of nucleotides in a double-helical structure? | bacteria | molecule | RNA | dna | DNA Double-Helical Structure DNA has a double-helical structure (Figure 2.23). It is composed of two strands, or polymers, of nucleotides. The strands are formed with bonds between phosphate and sugar groups of adjacent nucleotides. The strands are bonded to each other at their bases with hydrogen bonds, and the strands coil about each other along their length, hence the “double helix” description, which means a double spiral. |
The body is made up of how many types of tissue? | six | five | seven | four | As for all animals, your body is made of four types of tissue: epidermal, muscle, nerve, and connective tissues. Plants, too, are built of tissues, but not surprisingly, their very different lifestyles derive from different kinds of tissues. All three types of plant cells are found in most plant tissues. Three major types of plant tissues are dermal, ground, and vascular tissues. |
The great astronomer edwin hubble discovered that all distant galaxies are receding from our milky way galaxy with velocities proportional to their what? | dimensions | masses | paths | distances | (a) A jet airplane flying from Darwin, Australia, has an air speed of 260 m/s in a direction 5.0º south of west. It is in the jet stream, which is blowing at 35.0 m/s in a direction 15º south of east. What is the velocity of the airplane relative to the Earth? (b) Discuss whether your answers are consistent with your expectations for the effect of the wind on the plane’s path. (a) In what direction would the ship in Exercise 3.57 have to travel in order to have a velocity straight north relative to the Earth, assuming its speed relative to the water remains 7.00 m/s ? (b) What would its speed be relative to the Earth? 60. (a) Another airplane is flying in a jet stream that is blowing at 45.0 m/s in a direction 20º south of east (as in Exercise 3.58). Its direction of motion relative to the Earth is 45.0º south of west, while its direction of travel relative to the air is 5.00º south of west. What is the airplane’s speed relative to the air mass? (b) What is the airplane’s speed relative to the Earth? 61. A sandal is dropped from the top of a 15.0-m-high mast on a ship moving at 1.75 m/s due south. Calculate the velocity of the sandal when it hits the deck of the ship: (a) relative to the ship and (b) relative to a stationary observer on shore. (c) Discuss how the answers give a consistent result for the position at which the sandal hits the deck. The velocity of the wind relative to the water is crucial to sailboats. Suppose a sailboat is in an ocean current that has a velocity of 2.20 m/s in a direction 30.0º east of north relative to the Earth. It encounters a wind that has a velocity of 4.50 m/s in a direction of 50.0º south of west relative to the Earth. What is the velocity of the wind relative to the water? 63. The great astronomer Edwin Hubble discovered that all distant galaxies are receding from our Milky Way Galaxy with velocities proportional to their distances. It appears to an observer on the Earth that we are at the center of an expanding universe. Figure 3.64 illustrates this for five galaxies lying along a straight line, with the Milky Way Galaxy at the center. Using the data from the figure, calculate the velocities: (a) relative to galaxy 2 and (b) relative to galaxy 5. The results mean that observers on all galaxies will see themselves at the center of the expanding universe, and they would likely be aware of relative velocities, concluding that it is not possible to locate the center of expansion with the given information. |
What is friction that acts on objects while it is rolling over a surface called? | surface friction | blowing friction | opposing friction | rolling friction | Rolling friction is friction that acts on objects when they are rolling over a surface. Rolling friction is much weaker than sliding friction or static friction. This explains why most forms of ground transportation use wheels, including bicycles, cars, 4-wheelers, roller skates, scooters, and skateboards. Ball bearings are another use of rolling friction. You can see what they look like in the Figure below . They let parts of a wheel or other machine roll rather than slide over on another. |
Traditionally, mammals were divided into groups based on what? | their behaviors | their sizes | their colors | their characteristics | Traditionally, mammals were divided into groups based on their characteristics. Scientists took into consideration their anatomy (body structure), their habitats, and their feeding habits. Mammals are divided into three subclasses and about 26 orders. Some of the groups of mammals include:. |
What type of bonds do alkanes only contain? | hydrogen-carbon bonds | hydrogen bonds | carbon-hydrogen bonds | carbon-carbon single bonds | Alkanes contain only carbon-carbon single bonds. |
Which part of the wave helps make the wave bend and cause refraction? | bright part | dense part | heavy part | shallow part | Lymph that collects in tissues slowly passes into tiny lymph vessels. Lymph then travels from smaller to larger lymph vessels. Muscles around the lymph vessels contract and squeeze the lymph through the vessels. The lymph vessels also contract to help move the lymph along. Eventually, lymph reaches the main lymph vessels, which are located in the chest. From these vessels, lymph drains into two large veins of the cardiovascular system. This is how lymph returns to the blood. |
What are passed from one generation to the next so species can survive? | fluctuations | selections | mutations | adaptatioins | |
What kind of lines does a diffraction grating produce? | randomly spaced lines | nearly spaced lines | properly spaced lines | evenly spaced lines | 27.5 Single Slit Diffraction Light passing through a single slit forms a diffraction pattern somewhat different from those formed by double slits or diffraction gratings. Figure 27.21 shows a single slit diffraction pattern. Note that the central maximum is larger than those on either side, and that the intensity decreases rapidly on either side. In contrast, a diffraction grating produces evenly spaced lines that dim slowly on either side of center. |
Which type of ferns have yellow sporangia and no leaves? | Boston fern | Ostrich fern | Hothouse fern | whisk ferns | Forest and Kim Starr/Starr Environmental. Whisk ferns have yellow sporangia and no leaves . CC BY 3.0. |
Ice masses, acquifers, and the deep ocean are examples of water what? | fields | lakes | seas | reservoirs | The atmosphere is an exchange pool for water. Ice masses, aquifers, and the deep ocean are water reservoirs. |
This heat is used to convert water into steam, which is then used to turn a turbine, thus generating what? | heating power | solar power | radiation power | electrical power | The generation of electricity is critical for the operation of nearly all aspects of modern society. The following diagram illustrates the types of fuels used to generate electrical power in the Unites States. In 2009, almost 45% of the power generated in the U. S. was derived from coal, with natural gas making up another 23% of the total. The third primary source of electrical energy is nuclear power, which accounts for approximately 20% of the total amount generated. All of these fuels give off energy in the form of heat. This heat is used to convert water into steam, which is then used to turn a turbine, thus generating electrical power. |
What atmospheric layer lies above the highest altitude an airplane can go and below the lowest altitude a spacecraft can orbit? | thermosphere | stratosphere | troposphere | mesosphere | Not so fast. The mesosphere is the least known layer of the atmosphere. The mesosphere lies above the highest altitude an airplane can go. It lies below the lowest altitude a spacecraft can orbit. Maybe that's just as well. If you were in the mesosphere without a space suit, your blood would boil! This is because the pressure is so low that liquids would boil at normal body temperature. |
Where are sensors for thermoregulation concentrated in the brain? | medulla | thyroid | pituitary gland | the hypothalamus | |
What is the first step in the breakdown of glucose to extract energy for cellular metabolism? | photosynthesis | mutation | mitosis | glycolysis | 7.2 | Glycolysis By the end of this section, you will be able to: • Describe the overall result in terms of molecules produced in the breakdown of glucose by glycolysis • Compare the output of glycolysis in terms of ATP molecules and NADH molecules produced You have read that nearly all of the energy used by living cells comes to them in the bonds of the sugar, glucose. Glycolysis is the first step in the breakdown of glucose to extract energy for cellular metabolism. Nearly all living organisms carry out glycolysis as part of their metabolism. The process does not use oxygen and is therefore anaerobic. Glycolysis takes place in the cytoplasm of both prokaryotic and eukaryotic cells. Glucose enters heterotrophic cells in two ways. One method is through secondary active transport in which the transport takes place against the glucose concentration gradient. The other mechanism uses a group of integral proteins called GLUT proteins, also known as glucose transporter proteins. These transporters assist in the facilitated diffusion of glucose. Glycolysis begins with the six carbon ring-shaped structure of a single glucose molecule and ends with two molecules of a three-carbon sugar called pyruvate. Glycolysis consists of two distinct phases. The first part of the glycolysis pathway traps the glucose molecule in the cell and uses energy to modify it so that the six-carbon sugar molecule can be split evenly into the two three-carbon molecules. The second part of glycolysis extracts energy from the molecules and stores it in the form of ATP and NADH, the reduced form of NAD. |
What charge do atoms carry? | positive | negative | static | neutral | Atoms, which are always neutral in electric charge, contain electrons as well as protons and neutrons. An electron has an electrical charge of -1. If an atom has three electrons, infer how many protons it has. |
The pleura that surrounds the lungs consists of how many layers? | three | one | four | two | The pleura that surrounds the lungs consists of two layers, the ________. visceral and parietal pleurae. mediastinum and parietal pleurae. visceral and mediastinum pleurae. none of the above 14. Which of the following processes does atmospheric pressure play a role in? a. pulmonary ventilation b. production of pulmonary surfactant c. resistance d. surface tension 15. A decrease in volume leads to a(n) ________ pressure. |
Organisms that obtain food from outside themselves (i.e. they don't make their own food) are known as what? | fungi | autotrophs | zygotes | heterotrophs | Fungi are heterotrophs, meaning they obtain food from outside themselves. |
In scientific investigations, descriptive statistics are useful for summarizing the characteristics of large what? | tissues | organisms | questions | samples | The girls in the picture above make up a small sample—there are only four of them. In scientific investigations, samples may include hundreds or even thousands of people or other objects of study. Especially when samples are very large, it’s important to be able to summarize their overall characteristics with a few numbers. That’s where descriptive statistics come in. Descriptive statistics are measures that show the central tendency, or center, of a sample or the variation in a sample. |
The process of the cytoplasm splitting apart and the cell pinching in two is known as what? | budding | mitosis | electrolysis | cytokinesis | The cell wall grows toward the center of the cell. The cytoplasm splits apart, and the cell pinches in two. This is called cytokinesis . |
What kind of mountainous formation can often be found near trenches? | craters | earthquakes | caves | volcanoes | deep sea trenches : Trenches are found in the sea. Some are near the edges of continents. Trenches are found near chains of active volcanoes. An example is the line of the very deepest blue, off of western South America. |
Because it can be controlled intentionally, skeletal muscle is also called what type of muscle? | involuntary | automatic | necessary | voluntary | Skeletal muscle tissue forms skeletal muscles, which attach to bones and sometimes the skin and control locomotion and any other movement that can be consciously controlled. Because it can be controlled intentionally, skeletal muscle is also called voluntary muscle. When viewed under a microscope, skeletal muscle tissue has a striped or striated appearance. This appearance results from the arrangement of the proteins inside the cell that are responsible for contraction. The cells of skeletal muscle are long and tapered and have multiple nuclei on the periphery of each cell. Smooth muscle tissue occurs in the walls of hollow organs such as the intestines, stomach, and urinary bladder, and around passages such as in the respiratory tract and blood vessels. Smooth muscle has no striations, is not under voluntary control, and is called involuntary muscle. Smooth muscle cells have a single nucleus. Cardiac muscle tissue is only found in the heart. The contractions of cardiac muscle tissue pump blood throughout the body and maintain blood pressure. Like skeletal muscle, cardiac muscle is striated, but unlike skeletal muscle, cardiac muscle cannot be consciously controlled and is called involuntary muscle. The cells of cardiac muscle tissue are connected to each other through intercalated disks and usually have just one nucleus per cell. |
What effect in the atmosphere ensures that the earth maintains the correct temperature to support life? | smog effect | coriolis effect | ozone effect | greenhouse effect | When sunlight heats Earth’s surface, some of the heat radiates back into the atmosphere. Some of this heat is absorbed by gases in the atmosphere. This is the greenhouse effect , and it helps to keep Earth warm. The greenhouse effect allows Earth to have temperatures that can support life. |
Felsic, intermediate, mafic, and ultramafic are types of composition of what rock group? | metamorphic | Sedimentary | asteroids | igneous | Igneous rocks are classified by composition and texture. The composition can be felsic, intermediate, mafic, or ultramafic. The composition depends on the minerals the rock includes. A felsic rock will contain felsic minerals. |
What is the base of nearly all food chains on earth? | synthesis | glycolysis | atherosclerosis | photosynthesis | Photosynthesis is the base of nearly all food chains on Earth. This is true of marine food chains, too. |
The skull is a part of a vertebrate endoskeleton that encloses and protects what organ? | heart | nervous system | lung | brain | part of a vertebrate endoskeleton that encloses and protects the brain; also called the skull. |
The global pattern of precipitation is influenced by movements of what? | clouds | pollution masses | air valleys | air masses | The global pattern of precipitation is influenced by movements of air masses. For example, there is a global belt of dry air masses and low precipitation at about 30° N and 30° S latitude. |
What is the name of the region of a magnet that has the most pull? | tail | center | grid | pole | Imagine a huge bar magnet passing through Earth’s axis, as in the Figure below . This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts the most force. |
How many major forces of elevation cause allele frequencies to change? | three | one | five | four | There are four major forces of evolution that cause allele frequencies to change. They are mutation, gene flow, genetic drift, and natural selection. |
Where in the atom is a neutron found? | orbit | electron | proton | the nucleus | A neutron is one of three main particles that make up the atom. It is found in the nucleus and is neutral in electric charge. It has about the same mass and diameter as a proton. Neutrons are found in all atoms except for most atoms of hydrogen. |
In physics, what is defined as the average kinetic energy of the particles of matter? | magnetism | density | friction | temperature | No doubt you already have a good idea of what temperature is. You might say that it’s how warm or cool something feels. In physics, temperature is defined as the average kinetic energy of the particles of matter. When particles of matter move more quickly, they have more kinetic energy, so their temperature is higher. With a higher temperature, matter feels warmer. When particles move more slowly, they have less kinetic energy on average, so their temperature is lower. With a lower temperature, matter feels cooler. |
What organelles are known as the "power plants" of the cell? | golgi body | plastid | flagella | mitochondria | They have lots of mitochondria. Mitochondria are called the power plants of the cell, as these organelles are where most of the cell's energy is produced. Cells that need lots of energy have lots of mitochondria. |
Dalton's law and henry's law both describe aspects of what type of exchange? | liquid | energy | electron | gas | 22.4 Gas Exchange The behavior of gases can be explained by the principles of Dalton’s law and Henry’s law, both of which describe aspects of gas exchange. Dalton’s law states that each specific gas in a mixture of gases exerts force (its partial pressure) independently of the other gases in the mixture. Henry’s law states that the amount of a specific gas that dissolves in a liquid is a function of its partial pressure. The greater the partial pressure of a gas, the more of that gas will dissolve in a liquid, as the gas moves toward equilibrium. Gas molecules move down a pressure gradient; in other words, gas moves from a region of high pressure to a region of low pressure. The partial pressure of oxygen is high in the alveoli and low in the blood of the pulmonary capillaries. As a result, oxygen diffuses across the respiratory membrane from the alveoli into the blood. In contrast, the partial pressure of carbon dioxide is high in the pulmonary capillaries and low in the alveoli. Therefore, carbon dioxide diffuses across the respiratory membrane from the blood into the alveoli. The amount of oxygen and carbon dioxide that diffuses across the respiratory membrane is similar. Ventilation is the process that moves air into and out of the alveoli, and perfusion affects the flow of blood in the capillaries. Both are important in gas exchange, as ventilation must be sufficient to create a high partial pressure of oxygen in the alveoli. If ventilation is insufficient and the partial pressure of oxygen drops in the alveolar air, the capillary is constricted and blood flow is redirected to alveoli with sufficient ventilation. External respiration refers to gas exchange that occurs in the alveoli, whereas internal respiration refers to gas exchange that occurs in the tissue. Both are driven by partial pressure differences. |
What vesicles store neurotransmitters? | Golgi apparatus | hydrophobic | dendritic | synaptic | Secretory Vesicles contain materials that are to be excreted from the cell, such as wastes or hormones . Secretory vesicles include synaptic vesicles and vesicles in endocrine tissues. Synaptic vesicles store neurotransmitters. They are located at presynaptic terminals in neurons. When a signal reaches the end of an axon, the synaptic vesicles fuse with the cell membrane and release the neurotransmitter. The neurotransmitter crosses the synaptic junction, and binds to a receptor on the next cell. Some cells also produce molecules, such as hormones produced by endocrine tissues, needed by other cells. These molecules are stored in secretory vesicles and released when needed. Secretory vesicles also hold enzymes needed to make extracellular structures, such as the extracellular matrix of animal cells. |
What temperature scale is obtained by adding 273 degrees from the corresponding celsius temperature? | ph scale | whittle scale | seismic scale | kelvin scale | The Celsius scale is the standard SI temperature scale. It is equal to the Kelvin scale if you minus 273 from the Celsius reading. Water has a boiling point of and a freezing point of . |
Hemoglobin is a large molecule made up of proteins and iron. it consists of four folded chains of a protein called this? | insulin | peptide | histone | globin | Hemoglobin Hemoglobin is a large molecule made up of proteins and iron. It consists of four folded chains of a protein called globin, designated alpha 1 and 2, and beta 1 and 2 (Figure 18.7a). Each of these globin molecules is bound to a red pigment molecule called heme, which contains an ion of iron (Fe2+) (Figure 18.7b). |
A new species is said to have evolved if separated members of a species evolve genetic differences that prevent what from occurring with the original members?? | re-population | extinction | evolution | interbreeding | Assume that some members of a species become geographically separated from the rest of the species. If they remain separated long enough, they may evolve genetic differences. If the differences prevent them from interbreeding with members of the original species, they have evolved into a new species. Speciation that occurs in this way is called allopatric speciation . An example is described in the Figure below . |
What term describes the orientation of a body lying face-down? | Supine | Under | Diagnal | prone | A body that is lying down is described as either prone or supine. Prone describes a face-down orientation, and supine describes a face up orientation. These terms are sometimes used in describing the position of the body during specific physical examinations or surgical procedures. |
What happens to energy when an atom gains an electron? | it increases | it is folded | it is used | it is released | A: Energy is released when an atom gains an electron. Halogens release the most energy when they form ions. As a result, they are very reactive elements. |
What is the name of the second most electronegative element? | carbon | nitrogen | Hydrogen | oxygen | Oxygen has an oxidation state of -2 in most of its compounds. Oxygen is the second most electronegative element, so it also tends to be assigned all shared electrons. Exceptions include O 2 (oxidation state = 0), peroxides, in which two oxygen atoms are connected by a single bond (oxidation state usually = -1), and any compound in which oxygen is bonded to fluorine (pretty rare and reactive). |
What is the term for species evolving together? | specmutation | conjuration | interconnection | coevolution | Coevolution occurs when species evolve together. This often happens in species that have symbiotic relationships. Examples include flowering plants and their pollinators. |
Where do the eggs develop? | the follicles | the uterus | the glands | the ovaries | |
What's the other term for your wind pipe? | esophagus | cornea | cochlea | trachea | The trachea , or wind pipe, is a long tube that leads down to the chest. |
When food is scarce, starving cells secrete a molecule that stimulates neighboring cells to do what? | die off | compete | hoard energy | aggregate | |
What do cells secrete that binds to receptors? | proteins | stress | endorphans | factor | |
What is the term for the tube that carries sound waves into the ear? | tone canal | sound canal | flap canal | ear canal | The ear canal is a tube that carries sound waves into the ear. The sound waves travel through the air inside the ear canal to the eardrum. |
In the cardiovascular system, what blood vessels carry blood away from the heart? | cilia | veins | capillaries | arteries | The blood vessels are an important part of the cardiovascular system. They connect the heart to every cell in the body. Arteries carry blood away from the heart, while veins return blood to the heart ( Figure below ). |
Molecules in the gas phase can collide with the liquid surface and reenter the liquid via what? | liquidation | fermentation | combustion | condensation | pressure above the liquid. Molecules in the gas phase can collide with the liquid surface and reenter the liquid via condensation. Eventually, a steady state is reached in which the number of molecules evaporating and condensing per unit time is the same, and the system is in a state of dynamic equilibrium. Under these conditions, a liquid exhibits a characteristic equilibrium vapor pressure that depends only on the temperature. We can express the nonlinear relationship between vapor pressure and temperature as a linear relationship using the Clausius–Clapeyron equation. This equation can be used to calculate the enthalpy of vaporization of a liquid from its measured vapor pressure at two or more temperatures. Volatile liquids are liquids with high vapor pressures, which tend to evaporate readily from an open container; nonvolatile liquids have low vapor pressures. When the vapor pressure equals the external pressure, bubbles of vapor form within the liquid, and it boils. The temperature at which a substance boils at a pressure of 1 atm is its normal boiling point. |
What guards the opening between the right atrium and the right ventricle? | aorta | superior vena cava | brachiocephalic trunk | tricuspid valve | Right Atrium The right atrium serves as the receiving chamber for blood returning to the heart from the systemic circulation. The two major systemic veins, the superior and inferior venae cavae, and the large coronary vein called the coronary sinus that drains the heart myocardium empty into the right atrium. The superior vena cava drains blood from regions superior to the diaphragm: the head, neck, upper limbs, and the thoracic region. It empties into the superior and posterior portions of the right atrium. The inferior vena cava drains blood from areas inferior to the diaphragm: the lower limbs and abdominopelvic region of the body. It, too, empties into the posterior portion of the atria, but inferior to the opening of the superior vena cava. Immediately superior and slightly medial to the opening of the inferior vena cava on the posterior surface of the atrium is the opening of the coronary sinus. This thin-walled vessel drains most of the coronary veins that return systemic blood from the heart. The majority of the internal heart structures discussed in this and subsequent sections are illustrated in Figure 19.9. While the bulk of the internal surface of the right atrium is smooth, the depression of the fossa ovalis is medial, and the anterior surface demonstrates prominent ridges of muscle called the pectinate muscles. The right auricle also has pectinate muscles. The left atrium does not have pectinate muscles except in the auricle. The atria receive venous blood on a nearly continuous basis, preventing venous flow from stopping while the ventricles are contracting. While most ventricular filling occurs while the atria are relaxed, they do demonstrate a contractile phase and actively pump blood into the ventricles just prior to ventricular contraction. The opening between the atrium and ventricle is guarded by the tricuspid valve. |
The water cycle involves movement of water between air and what? | air | tree | animals | land | |
When we consider a chemical reaction, we need to take into account both the system and what? | time | date | fluctuations | sorroundings | When we consider a chemical reaction, we need to take into account both the system and the surroundings. The system includes the components involved in the chemical reaction itself. These will often take place in a flask, a beaker, a test tube, or some other container. The surroundings include everything that is not part of the system. When potassium reacts with water, part of the heat energy generated in the reaction is released into the surroundings. The boundary between system and surroundings is arbitrary, and it is generally chosen in a way that makes observations and calculations easier. |
What is a layer of tissue that lies between the shell and the body? | node | stem | silt | mantle | Two unique features of mollusks are the mantle and radula (see Figure above ). The mantle is a layer of tissue that lies between the shell and the body. It secretes calcium carbonate to form the shell. It forms a cavity, called the mantle cavity, between the mantle and the body. The mantle cavity pumps water for filter feeding. The radula is a feeding organ with teeth made of chitin. It is located in front of the mouth in the head region. Herbivorous mollusks use the radula to scrape food such as algae off rocks. Predatory mollusks use the radula to drill holes in the shells of their prey. |
In what country can some of the largest natural crystals be found? | canada | spain | germany | mexico | Some of the largest, and most beautiful, natural crystals can be found in the Naica mine, in Mexico. These gypsum crystals were formed over thousands of years. Groundwater that is rich in calcium and sulfur flowed through an underground cave. Check it out:. |
What are the primary producers in terrestrial biomes? | animals | soil | gases | plants | Plants are the primary producers in terrestrial biomes. They make food for themselves and other organisms by photosynthesis. The major plants in a given biome, in turn, help determine the types of animals and other organisms that can live there. |
Where are aerofoils found? | birds and cars | airplanes and plants | birds and busses | birds and airplanes | Birds also have wings that function as an aerofoil . The surface of the aerofoil is curved to help the bird control and use the air currents to fly. Aerofoils are also found on the wings of airplanes. |
What is the si unit for pressure? | le | watt | laurent | pascal | Summary Four quantities must be known for a complete physical description of a sample of a gas: temperature, volume, amount, and pressure. Pressure is force per unit area of surface; the SI unit for pressure is the pascal (Pa), defined as 1 newton per square meter (N/m2). The pressure exerted by an object is proportional to the force it exerts and inversely proportional to the area on which the force is exerted. The pressure exerted by Earth’s atmosphere, called atmospheric pressure, is about 101 kPa or 14.7 lb/in.2 at sea level. Atmospheric pressure can be measured with abarometer, a closed, inverted tube filled with mercury. The height of the mercury column is proportional to atmospheric pressure, which is often reported in units ofmillimeters of mercury (mmHg), also called torr. Standard atmospheric pressure, the pressure required to support a column of mercury 760 mm tall, is yet. |
Marine fishes take in divalent ions by incessantly drinking what? | algae | sand | oxygen | seawater | |
The simplest and smallest particle of matter that still has chemical properties of the element is called? | an isotope | a molecule | a nucleus | an atom | Inside of elements, you will find identical atoms. An atom is the simplest and smallest particle of matter that still has chemical properties of the element. Atoms are the building block of all of the elements that make up the matter in your body or any other living or non-living thing. Atoms are so small that only the most powerful microscopes can see them. |
Frequency and intensity are two measurable properties of what? | troughs | heat | lines | wave | All waves can be defined in terms of their frequency and intensity. |
While most mammals give birth to live young, monotremes can do what? | steal eggs | reproduce asexually | adopt offspring | lay eggs | Monotremes can lay eggs, but most mammals give birth to live young. |
What happens to old oceanic crust at convergent boundaries? | emerges | created | dissolves | destroyed | It’s much easier to precisely make mirrors than to precisely make glass lenses. For that reason, reflectors can be made larger than refractors. Larger telescopes can collect more light. This means that they can study dimmer or more distant objects. The largest optical telescopes in the world today are reflectors. Telescopes can also be made to use both lenses and mirrors. |
When electrons are shared between two atoms, they make a bond called a what? | hydrogen bond | metallic bond | ionic bond | covalent bond | Ionic bonding typically occurs when it is easy for one atom to lose one or more electrons and another atom to gain one or more electrons. However, some atoms won’t give up or gain electrons easily. Yet they still participate in compound formation. How? There is another mechanism for obtaining a complete valence shell: sharing electrons. When electrons are shared between two atoms, they make a bond called a covalent bond. Let us illustrate a covalent bond by using H atoms, with the understanding that H atoms need only two electrons to fill the 1s subshell. Each H atom starts with a single electron in its valence shell:. |
What happens to the temperature of matter as light is absorbed? | it drops | it stays the same | it triples | it increases | http://www. chem. ufl. edu/~itl/2045/lectures/lec_d. html. |
By shocking ocean water, earthquakes can cause what deadly ocean waves? | typhoons | deep currents | ebb tides | tsunamis | Earthquakes can cause tsunamis . These deadly ocean waves may result from any shock to ocean water. A shock could be a meteorite impact, landslide, or a nuclear explosion. But most come from large underwater earthquakes. |
Where are the desmosome found in a cell? | coating | epithelial | neuron | epithelium | A desmosome is a cell junction specialized for cell-to-cell adhesion. They are found in simple and stratified squamous epithelium, and in muscle tissue where they bind muscle cells to one another. These junctions are composed of complexes of cell surface adhesion proteins and linking proteins. These proteins have both an intracellular and extracellular region. Inside the cell, they attach to intracellular filaments of the cytoskeleton. Outside the cell, they attach to other adhesion proteins. |
An action potential that starts at the axon hillock moves along the axon only toward what? | polar synapses | nerve endings | ionic pathways | the synaptic terminals | |
Fission is a type of radioactivity in which large nuclei spontaneously break apart into what? | active nuclei | faster nuclei | light nuclei | smaller nuclei | Fission is a type of radioactivity in which large nuclei spontaneously break apart into smaller nuclei. |
Bones are the main organs of what system, which also includes cartilage and ligaments? | endocrine system | lymphatic system | digestive system | skeletal system | Bones are the main organs of the skeletal system. The skeletal system also includes cartilage and ligaments. |
Most waves strike the shore at an angle. this causes what? | fontaine drift | erosion | tide | longshore drift | Below the topsoil is the “B“ horizon. This is also called the subsoil . Soluble minerals and clays accumulate in the subsoil. Because it has less organic material, this layer is lighter brown in color than topsoil. It also holds more water due to the presence of iron and clay. There is less organic material in this layer. |
What is the difference between the daily high and the daily low? | sunrise and sunset | weather forecast | margin of error | tidal change | The difference between the daily high and the daily low is the tidal range. |
Spermatogonia are the stem cells of what male sex organs? | ovaries | Epididymis | Prostate | testes | Germ Cells The least mature cells, the spermatogonia (singular = spermatogonium), line the basement membrane inside the tubule. Spermatogonia are the stem cells of the testis, which means that they are still able to differentiate into a variety of different cell types throughout adulthood. Spermatogonia divide to produce primary and secondary spermatocytes, then spermatids, which finally produce formed sperm. The process that begins with spermatogonia and concludes with the production of sperm is called spermatogenesis. |
Sensory neurons transmit nerve impulses from sense organs and internal organs to the brain via the? | spinal column | nervous system | nerve endings | spinal cord | Sensory neurons transmit nerve impulses from sense organs and internal organs to the brain via the spinal cord. In other words, they carry information about the inside and outside environment to the brain. |
Sexually reproducing organisms alternate between which stages? | diploid and traploid | binary and diploid | binary and haploid | haploid and diploid | CHAPTER SUMMARY 7.1 Sexual Reproduction Nearly all eukaryotes undergo sexual reproduction. The variation introduced into the reproductive cells by meiosis appears to be one of the advantages of sexual reproduction that has made it so successful. Meiosis and fertilization alternate in sexual life cycles. The process of meiosis produces genetically unique reproductive cells called gametes, which have half the number of chromosomes as the parent cell. Fertilization, the fusion of haploid gametes from two individuals, restores the diploid condition. Thus, sexually reproducing organisms alternate between haploid and diploid stages. However, the ways in which reproductive cells are produced and the timing between meiosis and fertilization vary greatly. There are three main categories of life cycles: diploid-dominant, demonstrated by most animals; haploid-dominant, demonstrated by all fungi and some algae; and alternation of generations, demonstrated by plants and some algae. |
Acids turn blue litmus paper which color? | purple | grey | white | red | Certain indicator compounds, such as litmus, can be used to detect acids. Acids turn blue litmus paper red. |
The development of a head region is called what? | cocklebur | trichina | spore | cephalization | Most flatworms have a distinct head region that includes nerve cells and sensory organs, such as eyespots. The development of a head region, called cephalization , evolved at the same time as bilateral symmetry in animals. This process does not occur in cnidarians, which evolved prior to flatworms and have radial symmetry. |
Which hormone helps cells absorb sugar from the blood? | adrenaline | estrogen | cortisol | insulin | Endocrine system: A high concentration of sugar in the blood triggers secretion of insulin by an endocrine gland called the pancreas. Insulin is a hormone that helps cells absorb sugar from the blood. |
What is the number of electrons equal to in every electrically neutral atom? | nucleus | Electrons | molecules | protons | Electron Shells and the Bohr Model It should be stressed that there is a connection between the number of protons in an element, the atomic number that distinguishes one element from another, and the number of electrons it has. In all electrically neutral atoms, the number of electrons is the same as the number of protons. Thus, each element, at least when electrically neutral, has a characteristic number of electrons equal to its atomic number. An early model of the atom was developed in 1913 by Danish scientist Niels Bohr (1885–1962). The Bohr model shows the atom as a central nucleus containing protons and neutrons, with the electrons in circular orbitals at specific distances from the nucleus, as illustrated in Figure 2.6. These orbits form electron shells or energy levels, which are a way of visualizing the number of electrons in the outermost shells. These energy levels are designated by a number and the symbol “n. ” For example, 1n represents the first energy level located closest to the nucleus. |
Does climate change have a positive or negative effect on reproductive success? | both | neither | positive | negative | |
What is the most common form of dwarfism in humans? | malnutrition | anemia | alopecia | achondroplasia | It can be. Achondroplasia is the most common form of dwarfism in humans, and it is caused by a dominant mutation. The mutation can be passed from one generation to the next. Over 95% of unrelated individuals with Achondroplasia have the same mutation, making it one of the most common mutations in the human genome. Why?. |
What is the term for groups of three successive nucleotide bases in dna? | triple play | triads | tertiary bases | triplets | Overview of Transcription. Transcription uses the sequence of bases in a strand of DNA to make a complementary strand of mRNA. Triplets are groups of three successive nucleotide bases in DNA. Codons are complementary groups of bases in mRNA. |
The coccyx, or tailbone, results from the fusion of four small what? | alangulam vertebrae | rib vertebrae | arsine vertebrae | coccygeal vertebrae | Regions of the Vertebral Column The vertebral column originally develops as a series of 33 vertebrae, but this number is eventually reduced to 24 vertebrae, plus the sacrum and coccyx. The vertebral column is subdivided into five regions, with the vertebrae in each area named for that region and numbered in descending order. In the neck, there are seven cervical vertebrae, each designated with the letter “C” followed by its number. Superiorly, the C1 vertebra articulates (forms a joint) with the occipital condyles of the skull. Inferiorly, C1 articulates with the C2 vertebra, and so on. Below these are the 12 thoracic vertebrae, designated T1–T12. The lower back contains the L1–L5 lumbar vertebrae. The single sacrum, which is also part of the pelvis, is formed by the fusion of five sacral vertebrae. Similarly, the coccyx, or tailbone, results from the fusion of four small coccygeal vertebrae. However, the sacral and coccygeal fusions do not start until age 20 and are not completed until middle age. An interesting anatomical fact is that almost all mammals have seven cervical vertebrae, regardless of body size. This means that there are large variations in the size of cervical vertebrae, ranging from the very small cervical vertebrae of a shrew to the greatly elongated vertebrae in the neck of a giraffe. In a full-grown giraffe, each cervical vertebra is 11 inches tall. |
What is a pure substance that cannot be separated into any other substances called? | Spears | light | Cells | element | An element is a pure substance that cannot be separated into any other substances. There are 92 naturally occurring elements. |
How many different types of stresses are there? | three | five | seven | four | Stress is the force applied to a rock. There are four types of stresses:. |
A molecule has two structures that can be generated. what is this called? | ethnocentrism | resonance hybrids | congruence | isomerism | The cis isomer has the two single hydrogen atoms on the same side of the molecule, while the trans isomer has them on opposite sides of the molecule. In both molecules, the bonding order of the atoms is the same. In order for geometric isomers to exist, there must be a rigid structure in the molecule to prevent free rotation around a bond. If the double bond in an alkene was capable of rotating, the two geometric isomers above would not exist. In addition, the two carbon atoms must each have two different groups attached in order for there to be geometric isomers. Propene has no geometric isomers because one of the carbon atoms has two single hydrogens bonded to it. |
An antigen is a molecule that reacts with some component of the what response? | hormones | digestion | fight or flight | immune | Chapter 42 1 Figure 42.11 C 3 Figure 42.16 If the blood of the mother and fetus mixes, memory cells that recognize the Rh antigen can form late in the first pregnancy. During subsequent pregnancies, these memory cells launch an immune attack on the fetal blood cells. Injection of anti-Rh antibody during the first pregnancy prevents the immune response from occurring. 4 D 6 A 8 D 10 B 12 D 14 C 16 C 18 D 20 C 22 If the MHC I molecules expressed on donor cells differ from the MHC I molecules expressed on recipient cells, NK cells may identify the donor cells as “non-self” and produce perforin and granzymes to induce the donor cells to undergo apoptosis, which would destroy the transplanted organ. 24 An antigen is a molecule that reacts with some component of the immune response (antibody, B cell receptor, T cell receptor). An epitope is the region on the antigen through which binding with the immune component actually occurs. 26 The TH1 response involves the secretion of cytokines to stimulate macrophages and CTLs and improve their destruction of intracellular pathogens and tumor cells. It is associated with inflammation. The TH2 response is involved in the stimulation of B cells into plasma cells that synthesize and secrete antibodies. 28 T cells bind antigens that have been digested and embedded in MHC molecules by APCs. In contrast, B cells function themselves as APCs to bind intact, unprocessed antigens. 30 Cross reactivity of antibodies can be beneficial when it allows an individual's immune system to respond to an array of similar pathogens after being exposed to just one of them. A potential cost of cross reactivity is an antibody response to parts of the body (self) in addition to the appropriate antigen. |
What bodily system is primarily responsible for fighting pathogens in the body? | Muscular | digestion | Cardiovascular | immune | 21.5 | The Immune Response against Pathogens By the end of this section, you will be able to: • Explain the development of immunological competence • Describe the mucosal immune response • Discuss immune responses against bacterial, viral, fungal, and animal pathogens • Describe different ways pathogens evade immune responses Now that you understand the development of mature, naïve B cells and T cells, and some of their major functions, how do all of these various cells, proteins, and cytokines come together to actually resolve an infection? Ideally, the immune response will rid the body of a pathogen entirely. The adaptive immune response, with its rapid clonal expansion, is well suited to this purpose. Think of a primary infection as a race between the pathogen and the immune system. The pathogen bypasses barrier defenses and starts multiplying in the host’s body. During the first 4 to 5 days, the innate immune response will partially control, but not stop, pathogen growth. As the adaptive immune response gears up, however, it will begin to clear the pathogen from the body, while at the same time becoming stronger and stronger. When following antibody responses in patients with a particular disease such as a virus, this clearance is referred to as seroconversion (sero- = “serum”). Seroconversion is the reciprocal relationship between virus levels in the blood and antibody levels. As the antibody levels rise, the virus levels decline, and this is a sign that the immune response is being at least partially effective (partially, because in many diseases, seroconversion does not necessarily mean a patient is getting well). An excellent example of this is seroconversion during HIV disease (Figure 21.26). Notice that antibodies are made early in this disease, and the increase in anti-HIV antibodies correlates with a decrease in detectable virus in the blood. Although these antibodies are an important marker for diagnosing the disease, they are not sufficient to completely clear the virus. Several years later, the vast majority of these individuals, if untreated, will lose their entire adaptive immune response, including the ability to make antibodies, during the final stages of AIDS. |
Displacement, velocity, acceleration, and force are examples of what type of quantity that has magnitude and direction? | frequency | cycles | wave | vector | Vectors in Two Dimensions A vector is a quantity that has magnitude and direction. Displacement, velocity, acceleration, and force, for example, are all vectors. In one-dimensional, or straight-line, motion, the direction of a vector can be given simply by a plus or minus sign. In two dimensions (2-d), however, we specify the direction of a vector relative to some reference frame (i. , coordinate system), using an arrow having length proportional to the vector’s magnitude and pointing in the direction of the vector. Figure 3.9 shows such a graphical representation of a vector, using as an example the total displacement for the person walking in a city considered in Kinematics in Two Dimensions: An Introduction. We shall use the notation that a boldface symbol, such as D , stands for a vector. Its magnitude is represented by the symbol in italics, D , and its direction by θ . Vectors in this Text In this text, we will represent a vector with a boldface variable. For example, we will represent the quantity force with the vector F , which has both magnitude and direction. The magnitude of the vector will be represented by a variable in italics, such as. |
Gases such as co2 and methane can trap what energy in earth's atmosphere, before radiating it into space? | potential energy | mechanical energy | sunlight energy | thermal energy | Thermal energy can be trapped in Earth’s atmosphere by gases such as CO2, water vapor, methane, and chlorofluorocarbons before it can be radiated into space—like the effect of a greenhouse. It is not yet clear how large an increase in the temperature of Earth’s surface can be attributed to this phenomenon. Venus is an example of a planet that has a runaway greenhouse effect. The atmosphere of Venus is about 95 times denser than that of Earth and contains about 95% CO2. Because Venus is closer to the sun, it also receives more solar radiation than Earth does. The result of increased solar radiation and high CO2 levels is an average surface temperature of about 450°C, which is hot enough to melt lead. Data such as those in Figure 5.22 "Changes in Atmospheric CO" indicate that atmospheric levels of greenhouse gases have increased dramatically over the past 100 years, and it seems clear that the heavy use of fossil fuels by industry is largely responsible. It is not clear, however, how large an increase in temperature (global warming) may result from a continued increase in the levels of these gases. Estimates of the effects of doubling the preindustrial levels of CO2 range from a 0°C to a 4.5°C increase in the average temperature of Earth’s surface, which is currently about. |
What happens when heated water is released into a body of water? | geysers | crystalline pollution | gaseous pollution | thermal pollution | If heated water is released into a body of water, it may cause thermal pollution. Thermal pollution is a reduction in the quality of water because of an increase in water temperature. A common cause of thermal pollution is the use of water as a coolant by power plants and factories. This water is heated and then returned to the natural environment at a higher temperature. |
What term is used to describe a chemical released by an animal that affects the behavior or physiology of animals of the same species? | amino | enzyme | isolate | pheromone | The amount of material left over after a certain number of half-lives can be easily calculated. |
Producers at the base of ecological food webs are also known as? | mutualistic | endoscopic | symbiotic | autotrophic | |
What is the term for the gas in smog that can damage plants? | sulphur | dioxide | carbon | ozone | The ozone in smog may damage plants. The effects of ozone add up over time. Plants such as trees, which normally live a long time, are most affected. Entire forests may die out if ozone levels are very high. Other plants, including crop plants, may also be damaged by ozone. You can see evidence of ozone damage in Figure below . |
What must happen for two ions to form an ionic bond? | two ions need to have neutral charges | two ions need to have the same charge | Two ions need to be the same size | two ions need to have opposite charges | |
What is the study of the similarities and differences in the embryos of different species? | diversified embryology | example embryology | prenatal biology | comparative embryology | Comparative embryology is the study of the similarities and differences in the embryos of different species. Similarities in embryos are evidence of common ancestry. All vertebrate embryos, for example, have gill slits and tails. Most vertebrates, except for fish, lose their gill slits by adulthood. Some of them also lose their tail. In humans, the tail is reduced to the tail bone. Thus, similarities organisms share as embryos may be gone by adulthood. This is why it is valuable to compare organisms in the embryonic stage. See http://www. pbs. org/wgbh/evolution/library/04/2/pdf/l_042_03. pdf for additional information and a comparative diagram of human, monkey, pig, chicken and salamander embryos. |
What are the main organs of the respiratory system? | kidneys | ovaries | intestines | lungs | The lungs are the main organs of the respiratory system. This is where gases are exchanged between the air and the blood. Gases are also transported by the blood and exchanged between the blood and all the cells of the body. |
What do you call the traits that allow a plant, animal, or other organism to survive and reproduce in its environment? | settings | additions | advantages | adaptations | Every plant and animal depends on its traits to survive. Survival may include getting food, building homes, and attracting mates. Traits that allow a plant, animal, or other organism to survive and reproduce in its environment are called adaptations . |