Quizzes 1-3

Front 1

Which type of potential energy is stored in molecules of food and gasoline?LightIonicCovalentChemicalHeat

Back 1

Chemical

Front 2

Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example ofcompetitive inhibition.noncompetitive inhibition.feedback inhibition.positive feedback.irreversible inhibition.

Back 2

feedback inhibition.

Front 3

A child is brought to the hospital with a fever of 107°F. Doctors immediately order an ice bath to lower the child’s temperature. Which of the following statements offers the most logical explanation for this action?Elevated body temperature will increase reaction rates in the child’s cells and overload the limited number of enzymes found in the cell.Elevated body temperatures may denature enzymes. This would interfere with the cell’s abilities to catalyze various reactions.Elevated body temperatures will increase the energy of activation needed to start various chemical reactions in the body. This will interfere with the ability of enzymes to catalyze vital chemical reactions.Elevated body temperatures will have no effect on enzyme-mediated reactions.Elevated body temperatures cause molecules to vibrate more quickly and prevent enzymes from easily attaching to reactants. This would slow vital body reactions.

Back 3

Elevated body temperatures may denature enzymes. This would interfere with the cell’s abilities to catalyze various reactions.

Front 4

An enzyme is generally named by adding ______ to the end of the name of the ______."-ose," cell in which it is found"-ase," cell in which it is found"-ose," substrate"-ase," substrate"-ase," coenzyme

Back 4

"-ase," substrate

Front 5

Astrophysicists explain that eventually the sun will swell to become a red giant, engulf the earth and "burn out" with all forms of energy dispersing in a final "heat death." Compared with conditions today, the entropy of the universe then will _____.have increased greatly.have decreased greatly.remain the same because energy cannot be created or destroyed.have decreased minimally.not exist.

Back 5

have increased greatly.

Front 6

Most of a cell's enzymes are ________.lipidsproteinsamino acidsnucleic acidscarbohydrates

Back 6

proteins

Front 7

Which one of the following is true about the ATP molecule?It contains two phosphate groups.Extremely stable bonds link the second and third phosphate groups.It contains the six-carbon sugar hexose.It contains a nitrogenous base molecule called adenine.None of the choices are correct.

Back 7

It contains a nitrogenous base molecule called adenine.

Front 8

The term "phosphorylation" refers to theuse of an enzyme to break down ATP.transfer of a phosphate to a substrate - like ADP.taking away of phosphate molecules from enzymes.second law of thermodynamics relating to phosphorous function.subtraction of a phosphate from a substrate.

Back 8

transfer of a phosphate to a substrate - like ADP.

Front 9

Two basic kinds of enzyme inhibitors are properly called ________.in-play and out-of-playallosteric and functionally activecompetitive and noncompetitiveinduced fit and active sitecofactors and induced fit models

Back 9

competitive and noncompetitive

Front 10

The active site of an enzymeis where the coenzyme is located.is a specific bulge or protuberance on an enzyme.is a groove or crevice on the structure of the enzyme.will react with only one substrate no matter how many molecules may resemble the shape of the substrate.rigidly resists any alteration of its shape.

Back 10

is a groove or crevice on the structure of the enzyme.

Front 11

The processes of photosynthesis and cellular respiration are complementary. During these energy conversions, some energy islost in the form of heat.created in the form of heat.used to create light.All of the choices are correct.None of the choices are correct.

Back 11

lost in the form of heat.

Front 12

Which of the following is a coenzyme?zincVitamin B6ironiodinehydrogen ions

Back 12

Vitamin B6

Front 13

Which one of the following processes is endergonic?the burning of woodthe release of heat from the breakdown of glucosethe synthesis of glucose from carbon dioxide and waterthe breakdown of glucosecellular respiration

Back 13

the synthesis of glucose from carbon dioxide and water

Front 14

Which of the following organelles produces ATP?A. Golgi apparatusB. MitochondriaC. LysosomeD. RibosomeE. Both b and c are correct.

Back 14

Mitochondria

Front 15

Which of the following is consistent with the laws of physics governing energy?When a liter of gasoline is burned in a car engine, 100% of its energy goes into moving the car along the road.You eat a "quarter-pounder" hamburger and assemble exactly a quarter-pound of additional body weight on your body.Eventually sunlight that is absorbed on the earth returns to space as dispersed heat.A calorie of sunlight becomes a calorie of plant tissue that, eaten by you, becomes a calorie of heat lost in muscle "power."Chemical bonds are a case of converting energy to matter; breaking the bonds converts matter to energy.

Back 15

Eventually sunlight that is absorbed on the earth returns to space as dispersed heat.

Front 16

ATP is considered a high-energy compound because under cellular conditions, 7.3 kcal per mole of energy is released when a bond is broken between ______.the base adenine and the sugar ribose.the adenosine and the phosphate groups.the base adenine and the phosphate groups.the adenosine diphosphate and the third phosphate.All of the above bonds release energy as ATP is completely broken down.

Back 16

the adenosine diphosphate and the third phosphate.

Front 17

Which statement describes the currently accepted theory of how an enzyme and its substrate fit together?As the product is released, the enzyme breaks down.The enzyme is like a key that fits into the substrate, which is like a lock.The active site is permanently changed by its interaction with the substrate.As the substrate binds to the enzyme, the shape of the active site changes to accommodate the reaction.None of the choices are correct.

Back 17

As the substrate binds to the enzyme, the shape of the active site changes to accommodate the reaction.

Front 18

ATP isthe energy currency of a cellproduced by the destruction of ADPexpended in the process of photosynthesisproduced during the phosphorylation of any organic compound

Back 18

the energy currency of a cell

Front 19

Life's primary source of energy is ____.foodwaterheatATPentropy

Back 19

ATP

Front 20

When an enzyme catalyzes a reaction,it lowers the activation energy of the reaction.it raises the activation energy of the reaction.it becomes a product.it acts as a reactant.None of the choices are correct.

Back 20

it lowers the activation energy of the reaction.

Front 21

Enzymes are _______.A. influenced by temperatureB. influenced by pHC. not influenced by salinityD. both a and bE. All of the choices are correct.

Back 21

both a and b

Front 22

Which statement about energy transformations is true?In energy transformations, energy is conserved or recycled.Living organisms decrease entropy in the universe as energy is transformed from light to chemical energy.Energy is constantly being created in the universe.Entropy is constantly increasing in the universe.Energy transformations decrease entropy in the universe.

Back 22

Entropy is constantly increasing in the universe.

Front 23

Kinetic energy differs from chemical energy in that ______.kinetic energy is stored energy that has the potential to do work, and chemical energy is the energy of movementkinetic energy depends on the movement of atoms, whereas chemical energy depends on the movement of moleculeskinetic energy can be converted into various forms of energy, whereas chemical energy can only be converted into heatkinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of moleculeschemical energy is a particular form of kinetic energy

Back 23

kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules

Front 24

According to __________, energy cannot be created or destroyed.Aristotle's first principlethe first law of thermodynamicsthe second law of thermodynamicsthe third law of thermodynamicsEinstein's law of relativity

Back 24

the first law of thermodynamics

Front 25

Anything that prevents ATP formation will most likelyresult in cell death.force the cell to rely on lipids for energy.result in the conversion of kinetic energy to potential energy.force the cell to rely on ADP for energy.have no effect on the cell.

Back 25

result in cell death

Front 26

Which of the following is true of an energy barrier?It is the amount of energy that must be produced by the reactants to end a chemical reaction.It is higher than the activation energy of a reaction.It prevents the spontaneous breakdown of molecules in the cell.It can only be overcome with the use of enzymes.It may place chemical groups of the active site in position to catalyze the reaction.

Back 26

It prevents the spontaneous breakdown of molecules in the cell.

Front 27

The second law of thermodynamics states that____________.energy can be transformed into matter and, because of this, we can get something for nothing.energy can be destroyed only during nuclear reactions, such as those that occur inside the sun.if energy is gained by one region of the universe, another place in the universe also must gain energy to maintain the balance of nature.energy tends to become increasingly dispersed and unusable.

Back 27

energy tends to become increasingly dispersed and unusable.

Front 28

Which one of the following is false?An enzyme's function depends on its three-dimensional shape.Enzymes are very specific for certain substrates.Enzymes are used up in chemical reactions.Enzymes emerge unchanged from the reactions they catalyze.An enzyme binds to its substrate at the enzyme's active site.

Back 28

Enzymes are used up in chemical reactions.

Front 29

Coupling occurs when the energy released by an exergonic reaction is ______.used to drive another exergonic reaction.used to drive an endergonic reaction.lost as nonusable heat to the environment.used to decrease the entropy of the universe.All of the choices are correct.

Back 29

used to drive an endergonic reaction

Front 30

A coenzyme is ____.an ionic cofactor that interacts with an enzyme to allow it to work.a protein cofactor that interacts with an enzyme to allow it to work.a nonprotein organic cofactor that interacts with an enzyme to allow it to work.an ionic cofactor that interacts with an enzyme to inhibit it.a protein cofactor that interacts with an enzyme to inhibit it.

Back 30

a nonprotein organic cofactor that interacts with an enzyme to allow it to work.

Front 31

If you were to transfer a saltwater, single-celled protist to fresh water, which of the following is likely to happen?

Back 31

The cell will swell and burst

Front 32

Light microscopes

Back 32

use light and glass lenses to magnify an image.

Front 33

Long fibers of DNA and protein are called a

Back 33

chromatin.

Front 34

Osmosis can be defined as

Back 34

the diffusion of water across a membrane.

Front 35

Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of

Back 35

passive transport.

Front 36

The membranous compartmentalization of a cell

Back 36

allows different metabolic processes to occur simultaneously.

Front 37

Which of the following statements is consistent with the Cell Theory?

Back 37

The cell is the basic structural and functional unity of life.

Front 38

Membrane phospholipidsa. have hydrophobic heads that face the center of the membrane and are shielded from waterb. have hydrophilic tails that face outward and are exposed to waterc. often have kinks in their tails caused by the presence of a singe rather than double bound d. remain fluid because they are tightly packed against one another. e. none of the choices are correct

Back 38

None of the choices are correct

Front 39

Cilia differ from flagella in that

Back 39

cilia are typically more numerous and shorter than flagella.

Front 40

A scanning electron microscope is used to study __________, whereas a transmission electron microscope is used to study __________.a. live cells .... dead cellsb. cell surfaces .... internal cell structuresc. dead cells..... live cellsd. internal cell structures.... cell surfaces

Back 40

cell surfaces . . . internal cell structures

Front 41

The Golgi apparatus

Back 41

stores, modifies, and packages proteins.

Front 42

If you were to transfer a freshwater, single-celled protist to saltwater, which of the following is likely to happen?

Back 42

The cell will shrink.

Front 43

Smooth endoplasmic reticulum

Back 43

stores calcium ions in muscle cells.

Front 44

Active transporta. uses ATP as an energy sourceb. can move solutes of a concentration gradientc. requires the cell to expend energyd. is necessary to allow nerves to function properlye. all of the above

Back 44

All of the choices are correct.

Front 45

If a biologist said that eukaryotic cells get their power from bacteria, they would be referring to

Back 45

the mitochondria in our cells that may have originated as endosymbiotic bacteria.

Front 46

Contractile vacuoles

Back 46

prevent cells from bursting as a result of the influx of excess water.

Front 47

Which of the following cell structures is not associated with the breakdown of harmful substances or substances that are no longer needed by the cell?a. lysosomesb. mitochondriac. peroxisomesd. vacuolese. all of the choices play a role

Back 47

mitochondria

Front 48

The act of a white blood cell engulfing a bacterium is

Back 48

phagocytosis

Front 49

As cell size increases, the

Back 49

volume increases faster than the surface area.

Front 50

Which of the following statements is true?cells placed in an isotonic solution will swellcells placed in an hypotonic solution will swellcells placed in a hypotonic solution will shrinkcells placed in a hypotonic solution will remain the same size

Back 50

Cells placed in a hypotonic solution will swell.

Front 51

Which one of the following is not a function of membrain proteins? Membrane proteinsserve as enzymesattach the membrane to the cytoskeletonprovide cellulare identification tagsform junctions between cellsall of the choices are membrane protein functions

Back 51

All of the choices are membrane protein functions.

Front 52

A cell that has neither a net gain nor a net lose of water when it is immersed in a solution is

Back 52

isotonic to its environment.

Front 53

Cells that lack a membrane-bound nucleus are __________ cells.

Back 53

prokaryotic

Front 54

Secretory proteins are

Back 54

released from the cell through the plasma membrane.

Front 55

Large, round cells can overcome surface area to volume problems by

Back 55

becoming smaller, narrower or flatter.

Front 56

Phagocytosis is to eating as pinocytosis is to

Back 56

drinking.

Front 57

We can characterize the fluid mosaic model of a membrane as ____________ floating in a sea of ___________

Back 57

proteins; lipid

Front 58

Small, nonpolar, hydrophobic molecules such as fatty acids

Back 58

easily pass through a membrane's lipid bilayer.

Front 59

Plants with rigid cell walls are unable to do which process?diffusionosmosisactive transportphagoctyosis

Back 59

phagoctyosis

Front 60

Lysosomeshelp to digest worn-out or damaged organellesrecycle materials within the cellfuse with food vacuoles to expose nutrients to lysosomal enzymesdestroy harmful bacterial engulfed by white blood cellsall of the choices are correct

Back 60

All of the choices are correct.

Front 61

The nucleus of an atom containsprotons and neutrons.protons and electrons.only neutrons.only protons.only electrons.

Back 61

protons and neutrons.

Front 62

The tree in your backyard is home to two cardinals, a colony of ants, a wasp's nest (a colony of wasps), two squirrels, and millions of bacteria. Together, all of these organisms representa species.a community.a population.an ecosystem.the biosphere.

Back 62

a community.

Front 63

DNA differs from RNA because DNAcontains thymine in place of uracil.consists of a single rather than a double polynucleotide strand.contains the sugar ribose rather than the sugar deoxyribose.contains phosphate groups not found in RNA.All of the above choices are correct.

Back 63

contains thymine in place of uracil.

Front 64

A(n) __________ forms when two atoms share electrons.ionelementcovalent bondionic bond

Back 64

covalent bond

Front 65

A scientist examining a group of cells under the microscope notices the presence of nuclei within these cells. Chemical tests reveal that each cell is photosynthetic and is surrounded by a wall composed of cellulose. These cells must come from an organism that is a member of the KingdomMonera.Protista.Plantae.Fungi.Animalia.

Back 65

Plantae

Front 66

Many names for sugars end in the suffix-acid.-ose.-hyde.-ase.-ing.

Back 66

-ose.

Front 67

Compared to a solution of pH3, a solution of pH1 is100 times more acidic.10 times more acidic.neutral.10 times more basic.100 times more basic.

Back 67

100 times more acidic.

Front 68

The term biodiversity refers toall of the non-living components of any ecosystem.how evolution specifically works by natural selection.the tremendous variety of life all around us on Earth.the amount of food available in any specific habitat.the fact that producers always make enough food for all consumers.

Back 68

the tremendous variety of life all around us on Earth.

Front 69

In plants, the transport of water from roots to leaves against the force of gravity is possible due to this property of water:Water's versatility as a solvent.Cohesion.Adhesion.Evaporative cooling.All of the above.

Back 69

Cohesion

Front 70

As ice melts,hydrogen bonds are broken.water molecules become less tightly packed.the water becomes less dense.covalent bonds form.All of the choices are true.

Back 70

hydrogen bonds are broken.

Front 71

Nucleotidescontain nitrogenous bases.contain sugar molecules.contain phosphate groups.can be linked together to form nucleic acids.All of the choices are correct.

Back 71

All of the choices are correct.

Front 72

Sucrose is formedfrom two glucose molecules.from two monosaccharides by dehydration synthesis.when ionic bonds link two monosaccharides.when water molecules are added to two monosaccharides.when glucose and lactose are combined.

Back 72

from two monosaccharides by dehydration synthesis.

Front 73

Life is organized in a hierarchical fashion. Which one of the following sequences illustrates that hierarchy as it increases in complexity?
ecosystem → population → organ system → cell → community → molecule → organ → organism → tissue
cell → molecule → organ system → organ → population → tissue → organism → ecosystem → community
organism → organ system → tissue → population → organ → community → cell → ecosystem → molecule
molecule → cell → tissue → organ → organ system → organism → population → community → ecosystem

ecosystem → molecule → cell → tissue → organism → organ system → organ → community

Back 73

molecule → cell → tissue → organ → organ system → organism → population → community → ecosystem

Front 74

Carbon is able to form an immense diversity of

organic molecules because of carbon's

tendency to form covalent bonds.

ability to bond with up to four other atoms.

capacity to form single and double bonds.

ability to bond together to form extensive, branched, or unbranched carbon skeletons.

All of the choices are correct.

Back 74

All of the choices are correct.

Front 75

A diet high in animal products may increase the risk for atherosclerosis. This is because

most animal fats are unsaturated and most animal products contain high levels of steroids.

most animal fats are hydrogenated oils and most animal products contain high levels of phospholipids.

most animal fats are used for energy storage and most animal products contain high levels of unsaturated fats.

most animal fats are saturated and some animal products contain trans fats.

most animal products contain high levels of unsaturated oils and anabolic steroids.

Back 75

most animal fats are saturated and some animal products contain trans fats.

Front 76

Genetic information is encoded in

thequaternary structure of a protein.

sequence of nucleotides in DNA.

degree of saturation of fatty acids.

length of glycogen.

linear sequence of amino acids in a polypeptide.

Back 76

sequence of nucleotides in DNA.

Front 77

Your instructor asks you to look into your microscope to see a prokaryotic cell. You will be looking for a cell thathas

a nucleus and a membrane.

has a membrane, but no nucleus.

makes up most of the tissues of your body.

is much larger than most cells in your body.

does not use DNA to code genetic information.

Back 77

has a membrane, but no nucleus.

Front 78

In conducting a proper scientific experiment, which of the following would you not do?

Conduct research into past experiments on the topic.

Change the data that you collect so that it matches how you thought the experiment would come out.

Formulate a hypothesis before you begin collecting data.

Include a control group in your experiment.Repeat the experiment a number of times and make sure you have a large sample size.

Back 78

Change the data that you collect so that it matches how you thought the experiment would come out.

Front 79

Which one of the following lists contains only polysaccharides?

sucrose, starch, and cellulose

starch, amino acids, and glycogen

cellulose, starch, and glycogen

nucleotides, glycogen, and cellulose

fructose, cellulose, and glucose

Back 79

cellulose, starch, and glycogen

Front 80

Which one of the following statements is not consistent with Darwin's mechanism of natural selection?

Individuals in a population exhibit variations, some of which are heritable.

Individual organisms exhibit genetic change during their life spans to better fit their environment.

Factors in the environment result in some organisms with better reproductive success than others.

Natural selection is based in part on the overproduction of offspring.

Natural selection can lead to the appearance of new species.

Back 80

Individual organisms exhibit genetic change during their life spans to better fit their environment.

Front 81

Glucose molecules are to starch as __________ are to proteins.

oils

amino acids

fatty acids

waxes

lards

Back 81

amino acids

Front 82

The formation of systems typically results in the appearance of novel characteristics called

emergent properties.

negentropic domains.

disengaged traits.

reoccurring phenomena.

renewed characteristics.

Back 82

emergent properties.

Front 83

A scientist performs a controlled experiment. This means thatthe experiment is

repeated many times to ensure that the results are accurate.

the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data.

two experiments are conducted, one differing from the other by only a single variable.

two experiments are conducted, one differing from the other by two or more variables.

one experiment is performed, but the scientist controls the variables.

Back 83

two experiments are conducted, one differing from the other by only a single variable.

Front 84

The smallest unit of an element is

an atom.

an electron.

a neutron.

a proton.

Back 84

an atom.

Front 85

The ultimate source of energy flowing into nearly all ecosystems is

wind.

sunlight.

electricity.

geothermal vents.

radioactivity.

Back 85

sunlight.

Front 86

The ability of water molecules to form hydrogen bonds with other water molecules is critical to

evaporative cooling of skin surfaces.

the movement of water from the roots of a tree to its leaves.

the milder temperatures of coastal regions compared to inland areas.

the ability of certain insects to walk on the surface of water.all of these factors.

Back 86

all of these factors.

Front 87

A solute is

the dissolving agent of a solution.

the liquid portion of a solution.

usually water in living cells.

the substance that is dissolved in solution.

the dissolving agent of a solution, which is usually oxygen in living cells.

Back 87

the substance that is dissolved in solution.

Front 88

A consumer eating a producer represents

a transfer of chemical nutrients and energy.

a transfer of chemical nutrients but not a transfer of energy.

a transfer of energy but not a transfer of chemical nutrients.

neither a transfer of chemical nutrients nor a transfer of energy.

Back 88

a transfer of chemical nutrients and energy.

Front 89

A hypothesis is

the same as a theory.

a tentative answer to some question.

an explanatory idea that is broad in scope and supported by a large body of evidence.

a widely accepted idea about a phenomenon.

a widely accepted theory that is broad in scope and supported by a large body of evidence.

Back 89

a tentative answer to some question.

Front 90

Which of the following statements about radioactive isotopes is/are true?

The nuclei of radioactive isotopes are unusually stable, but the atoms tend to lose electrons.

When given a choice between radioactive and nonradioactive isotopes of the same atom, living cells are more likely to incorporate the radioactive isotopes into their structures.

The tracers typically used for diagnosing medical problems remain radioactive in the body for a number of years, but give off very low levels of radioactive energy.

The energy emitted by radioactive isotopes can break chemical bonds and cause molecular damage in cells.

All of the choices are true.

Back 90

The energy emitted by radioactive isotopes can break chemical bonds and cause molecular damage in cells.