Discover Biology 6th Edition By Anu Singh-Cundy - Test Bank

Discover Biology 6th Edition By Anu Singh-Cundy – Test Bank

 

Instant Download – Complete Test Bank With Answers

 

 

Sample Questions Are Posted Below

 

Chapter 05: Energy, Metabolism, and Enzymes

 

MULTIPLE CHOICE

 

1. The energy required for life processes must be extracted from an organism’s

a.	nucleus.	c.	predators.
b.	environment.	d.	biosynthesis.

 

 

ANS:  B                    DIF:    Easy               REF:   5.1                 OBJ:   5.1 | 5.2

MSC:  Remembering

 

2. A spherical rock rests at the top of a steep hill. The rock has________ energy.

a.	potential	c.	kinetic
b.	chemical	d.	no

 

 

ANS:  A                    DIF:    Easy               REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

3. Imagine a mousetrap with the spring arm set and latched, and with the level of potential energy high. This potential energy was added to the mousetrap

a.	when it was first constructed.
b.	as kinetic energy when the arm was pulled back and latched.
c.	when the latch was released and the arm sprang forward.
d.	when the various materials used to construct the mousetrap were selected.

 

 

ANS:  B                    DIF:    Moderate       REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

4. The second law of thermodynamics states that

a.	metabolic reactions must be balanced.
b.	the flow of energy connects living things to their environment.
c.	energy can be created but not destroyed.
d.	systems tend to become more disorderly.

 

 

ANS:  D                    DIF:    Easy               REF:   5.1                 OBJ:   5.1

MSC:  Remembering

 

5. Living systems must work to remain ordered; they pass off their disorder to the universe in the form of

a.	light.	c.	metabolic heat.
b.	sound.	d.	water.

 

 

ANS:  C                    DIF:    Easy               REF:   5.1                 OBJ:   5.1

MSC:  Understanding

 

6. The reuse of the same carbon molecules by plants, animals, and their environments over time is known as

a.	activation energy.	c.	carbon cycling.
b.	a consumption tree.	d.	the third law of thermodynamics.

 

 

ANS:  C                    DIF:    Easy               REF:   5.1                 OBJ:   5.2

MSC:  Applying

 

7. Photosynthetic organisms capture energy from sunlight and convert it into chemical bonds by forming

a.	sugars.	c.	work.
b.	enzymes.	d.	heat.

 

 

ANS:  A                    DIF:    Easy               REF:   5.1                 OBJ:   5.2

MSC:  Applying

 

8. During photosynthesis, light energy is converted into chemical energy, which is a type of

a.	potential energy.	c.	heat.
b.	kinetic energy.	d.	activation energy.

 

 

ANS:  A                    DIF:    Moderate       REF:   5.1                 OBJ:   5.1 | 5.2

MSC:  Remembering

 

9. In photosynthesis, the carbon used to make sugars is

a.	provided by enzymes.	c.	extracted from DNA.
b.	provided by carbon dioxide.	d.	oxidized.

 

 

ANS:  B                    DIF:    Moderate       REF:   5.1                 OBJ:   5.2

MSC:  Applying

 

10. When humans cut down trees for lumber to build permanent structures, what aspect of metabolic cycling is disrupted?

a.	The oxidation of wood products increases the amount of photosynthesis that can occur.
b.	The biosynthetic reactions that happen in the lumber cause too much catabolism to occur.
c.	Carbon and other atoms tied up in wooden structures are not being recycled into other living organisms.
d.	The DNA in the wood is unable to obey the first law of thermodynamics.

 

 

ANS:  C                    DIF:    Difficult         REF:   5.1                 OBJ:   5.2

MSC:  Applying

 

11. Plants and animals use different energy storage molecules, yet they both use the same mechanism to burn their stored energy. How can plants and animals both be successful, even though they burn different energy storage molecules?

a.	The internal components of plant and animal cells are identical.
b.	The second law of thermodynamics states that all cells have the same energy transfer system.
c.	Breaking the chemical bonds of a storage molecule transfers energy, no matter what molecule is stored.
d.	All organisms have the same enzymes to catalyze their energy-producing reactions.

 

 

ANS:  C                    DIF:    Difficult         REF:   5.1                 OBJ:   5.2

MSC:  Understanding

 

12. The term thermal energy describes the

a.	orderly movement of electrons along a conductor (such as a wire).
b.	movement of photons as they travel through space.
c.	attractive power of two magnets toward each other.
d.	random movement or vibration of the molecules of any substance (for example, water molecules in a beaker).

 

 

ANS:  D                    DIF:    Easy               REF:   5.1                 OBJ:   5.1

MSC:  Remembering

 

We can predict the amount of energy that will be released during a chemical reaction (as shown in the illustration) because the ________ law of thermodynamics states that ________.

a.	first; energy and matter are equivalent
b.	second; any use of energy affects the entire universe
c.	first; the total amount of energy in a defined system remains constant
d.	second; energetic systems become less organized over time

 

 

ANS:  C                    DIF:    Difficult         REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

14. In accordance with the first law of thermodynamics, the energy in a gallon of gas consumed in a mileage test is equal to the

a.	amount of work performed (a calculation based on miles traveled and the weight of the vehicle).
b.	amount of work performed plus the heat created from the friction of moving parts.
c.	amount of work performed plus the heat from friction, plus the heat of the exhaust from the motor.
d.	amount of work performed plus heat from friction, plus heat from the exhaust, plus the potential energy of combustion products in the exhaust.

 

 

ANS:  D                    DIF:    Difficult         REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

Examine this illustration. Which of the following statements best describes why heat is flowing from the worker?

a.	The worker was exposed to the sun while working outside and simply got hot.
b.	The conversion of metabolic energy into muscle contraction is not 100 percent efficient, and some of the energy is lost as heat.
c.	Using a hammer, paintbrush, or any other tool generates friction and heat in the arm; this friction and heat must be released to maintain homeostasis.
d.	Energy and matter are equivalent; the conversion of the worker’s body mass to kinetic energy requires a reduction of body mass.

 

 

ANS:  B                    DIF:    Moderate       REF:   5.1                 OBJ:   5.1

MSC:  Understanding

 

Consider the change in the status of the polymers in the living cell and the dead cell, as shown in the illustration. Which of the following natural processes would best exemplify this change?

a.	the conversion of living tissue to rock during fossilization
b.	the decomposition of a fallen tree trunk on the forest floor
c.	the conversion of the wax in a burning candle to carbon dioxide and water
d.	the development of a fertilized egg into a large, multicellular, sexually reproducing organism

 

 

ANS:  B                    DIF:    Moderate       REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

17. All molecules have a combination of kinetic energy and potential energy. If an external heat source were used to increase the kinetic energy of a group of molecules, the group’s potential energy would

a.	decline, because the sum of kinetic energy and potential energy always equals 100 percent.
b.	be unaffected, because no changes in the bonding pattern of the molecules would take place.
c.	also increase, because potential energy and kinetic energy are directly proportional to each other.
d.	decrease, because the potential energy is inversely proportional to the kinetic energy.

 

 

ANS:  B                    DIF:    Difficult         REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

18. Organisms that maintain a constant body temperature rely on the heat produced by cells. Where does this heat come from?

a.	Cells have special metabolic pathways that are exclusively for the production of heat.
b.	Mitochondria produce heat in the form of ATP.
c.	Plants store heat as they perform photosynthesis; when an organism digests a plant, that heat is released.
d.	Heat is a natural by-product of most chemical reactions.

 

 

ANS:  D                    DIF:    Difficult         REF:   5.1                 OBJ:   5.1

MSC:  Understanding

 

19. The heat given off by living systems can increase the likelihood that a given chemical reaction will take place. Why?

a.	The enzymes that catalyze reactions in living systems increasingly work better as the temperature decreases.
b.	The heat lowers the internal cellular temperature, enabling reactions to proceed more quickly.
c.	The heat enables photosynthesis to happen more rapidly.
d.	The heat speeds molecular movement, increasing the likelihood of collisions between an enzyme and its substrate.

 

 

ANS:  D                    DIF:    Difficult         REF:   5.1 | 5.3          OBJ:   5.1 | 5.3

MSC:  Understanding

 

20. Heat speeds up chemical reactions by

a.	causing the cell to produce enzymes that lower the activation energy of the reactions.
b.	decreasing the amount of oxygen available for redox reactions.
c.	inhibiting catabolic reactions and promoting anabolic reactions.
d.	causing reactants to collide more often.

 

 

ANS:  D                    DIF:    Moderate       REF:   5.1 | 5.3 | 5.5   OBJ:   5.1

MSC:  Applying

 

21. Complex molecules are built from smaller organic compounds by using energy to drive ________ reactions.

a.	catabolic	c.	hydrolysis
b.	anabolic	d.	redox

 

 

ANS:  B                    DIF:    Easy               REF:   5.2                 OBJ:   5.2 | 5.3 | 5.5

MSC:  Remembering

 

22. In the chemical reaction C₆H₁₂O₆ + 6 O₂ ® 6 CO₂ + 6 H₂O, the 6 CO₂ molecules are some of the

a.	substrates.	c.	enzymes.
b.	products.	d.	reactants.

 

 

ANS:  B                    DIF:    Easy               REF:   5.2                 OBJ:   5.3 | 5.5

MSC:  Applying

 

This graph depicts the energy flow over the course of a chemical reaction. The graph indicates that

a.	the products of this reaction have more energy than the substrates.
b.	this reaction requires an input of energy to convert glucose and O2 into H2O and CO2.
c.	this reaction can run in only one direction (from left to right in the graph).
d.	this reaction occurs only in the presence of an enzyme.

 

 

ANS:  B                    DIF:    Moderate       REF:   5.2                 OBJ:   5.3 | 5.5

MSC:  Applying

 

24. A decrease in potential energy between reactants and products is typical for which of the following types of chemical reactions?

a.	anabolic reactions
b.	catabolic reactions
c.	the formation of peptide bonds
d.	reactions that happen without the aid of an enzyme

 

 

ANS:  B                    DIF:    Moderate       REF:   5.2                 OBJ:   5.5

MSC:  Applying

 

25. A molecule of sugar slowly burns in a cell. Compared with the original sugar molecules, the products of these catabolic reactions are ________ and have ________.

a.	less stable; more energy	c.	more stable; less energy
b.	more stable; more energy	d.	less stable; less energy

 

 

ANS:  C                    DIF:    Difficult         REF:   5.2                 OBJ:   5.5

MSC:  Applying

 

26. The metabolism of living organisms comprises a series of catabolic reactions and anabolic reactions; both types of reactions are very carefully controlled, enabling the organism to

a.	minimize the release of carbon dioxide into the atmosphere.
b.	assess its metabolic state and respond appropriately.
c.	avoid consuming its food resources too quickly.
d.	capture as much of the released energy as possible.

 

 

ANS:  D                    DIF:    Difficult         REF:   5.2                 OBJ:   5.3 | 5.4 | 5.5 | 5.8

MSC:  Applying

 

27. Which of the following substances is either consumed or synthesized in a large number of cellular reactions?

a.	sugars	c.	DNA
b.	enzymes	d.	ATP

 

 

ANS:  D                    DIF:    Easy               REF:   5.2                 OBJ:   5.3 | 5.5

MSC:  Remembering

 

28. When ATP breaks down into ADP and a free phosphate group, which of the following processes occurs?

a.	ADP absorbs energy and transfers it to enzymes.
b.	Energy is released and can be used to power cellular activities.
c.	ADP becomes the active site in an enzyme.
d.	The energy in the broken bond is transferred to the phosphate group.

 

 

ANS:  B                    DIF:    Easy               REF:   5.2                 OBJ:   5.3 | 5.4

MSC:  Understanding

 

29. Which of the following compounds is the LEAST oxidized?

a.	C6H12O6	c.	CH4
b.	CO2	d.	HCOOH

 

 

ANS:  C                    DIF:    Difficult         REF:   5.2                 OBJ:   5.3 | 5.4 | 5.5

MSC:  Applying

 

30. In the chemical reaction CH₂O + O₂ ® CO₂ + H₂O, which of the following results occurs?

a.	Carbon is reduced and hydrogen is oxidized.
b.	Carbon is oxidized and oxygen is reduced.
c.	Carbon and hydrogen are reduced.
d.	Carbon and oxygen are oxidized.

 

 

ANS:  B                    DIF:    Difficult         REF:   5.2                 OBJ:   5.3 | 5.5

MSC:  Applying

 

31. Biosynthetic reactions require many things, including ________ and ________.

a.	carbon dioxide; water	c.	enzymes; ATP
b.	glucose; water	d.	sunlight; CTP

 

 

ANS:  C                    DIF:    Moderate       REF:   5.2                 OBJ:   5.3 | 5.4 | 5.5 | 5.6 | 5.8

MSC:  Understanding

 

32. Some kinds of drain cleaners use enzymes rather than strong, more dangerous chemicals. These enzymes are most likely able to

a.	catalyze a catabolic reaction.
b.	raise the activation energy of the reaction that clears the clog.
c.	create energy that can be used to break up the clog.
d.	let excess heat be passed off into the environment.

 

 

ANS:  A                    DIF:    Difficult         REF:   5.2 | 5.3          OBJ:   5.5 | 5.6

MSC:  Applying

 

33. Which of the following statements about enzymes is true?

a.	In a human cell, one enzyme usually catalyzes no more than five different chemical reactions.
b.	In a human cell, nearly all chemical reactions are catalyzed by enzymes.
c.	In a human cell, enzymes must be constantly replaced as they are used up in the reactions they catalyze.
d.	In a human cell, some enzymes are specialized to store activation energy.

 

 

ANS:  B                    DIF:    Easy               REF:   5.3                 OBJ:   5.4 | 5.6 | 5.8

MSC:  Remembering

 

34. Most enzymes are members of a special class of

a.	proteins.	c.	chemical bonds.
b.	nucleotides.	d.	hormones.

 

 

ANS:  A                    DIF:    Easy               REF:   5.3                 OBJ:   5.4 | 5.6 | 5.8

MSC:  Remembering

 

35. What do catalysts and enzymes have in common?

a.	They both decrease the number of collisions between substrate molecules during a reaction.
b.	They both increase the amount of activation energy required for a reaction to occur.
c.	They both increase the amount of substrate available for a reaction.
d.	They both decrease the amount of activation energy required for a reaction to occur.

 

 

ANS:  D                    DIF:    Easy               REF:   5.3                 OBJ:   5.4 | 5.6 | 5.8

MSC:  Understanding

 

36. Imagine a chemical reaction during which a solution turns from red to green very slowly. If a small piece of platinum is placed in the solution, the change occurs much more rapidly, yet the platinum remains unchanged; this result happens because the platinum

a.	provides activation energy.	c.	is a catalyst.
b.	is an enzyme.	d.	is an oxidizing agent.

 

 

ANS:  C                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6

MSC:  Applying

 

37. Which of the following statements about the role of enzymes in chemical reactions is true?

a.	An enzyme can be used for many different kinds of chemical reactions.
b.	An enzyme is permanently changed during a chemical reaction.
c.	An enzyme has a special site where the products bind before the reaction begins.
d.	An enzyme lowers the activation energy of a particular reaction.

 

 

ANS:  D                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6

MSC:  Applying

 

38. In the chemical reaction H₂O + CO₂ + carbonic anhydrase ® H⁺ + HCO₃^– + carbonic anhydrase, the carbonic anhydrase is a(n)

a.	reactant.	c.	enzyme.
b.	product.	d.	active site.

 

 

ANS:  C                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6

MSC:  Applying

 

39. An enzyme and its substrate find each other by

a.	chance encounter.	c.	catalysis.
b.	magnetic attraction.	d.	oxidative reactions.

 

 

ANS:  A                    DIF:    Easy               REF:   5.3                 OBJ:   5.6

MSC:  Remembering

 

40. Enzymes can catalyze a chemical reaction only if

a.	they encounter a molecule of ATP.
b.	their active site is sufficiently oxidized.
c.	they have both products in their active site at the same time.
d.	they encounter a substrate that fits their active site.

 

 

ANS:  D                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6

MSC:  Applying

 

This illustration diagrams the action of an enzyme. Notice that the enzyme is more tightly wrapped around the substrates in Step 2 than it is in Step 1. Why?

a.	When a substrate locks into an enzyme’s active site, the enzyme changes shape to mold itself around the substrates.
b.	Generally, the size of a substrate is larger than the size of the active site into which it must fit. When the substrate enters the active site, the active site must stretch to fit around it.
c.	Before catalysis can occur, a substrate must change its shape so that it fits into the enzyme’s active site more precisely.
d.	Most active sites are designed to hold only one substrate. In this diagram, two substrates enter the active site, creating a tighter fit.

 

 

ANS:  A                    DIF:    Difficult         REF:   5.3                 OBJ:   5.5

MSC:  Understanding

 

42. Sometimes enzymes need particular ions or small molecules to reach their highest activity; these ions or small molecules are called

a.	inhibitors.	c.	activators.
b.	cofactors.	d.	polyfactorials.

 

 

ANS:  B                    DIF:    Easy               REF:   5.3                 OBJ:   5.6

MSC:  Remembering

 

43. Which of the following conditions does NOT disrupt the three-dimensional shape of enzymes or alter their ability to bind to their substrates?

a.	cold temperatures	c.	very high salt concentrations
b.	high acidity	d.	high alkalinity

 

 

ANS:  A                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6

MSC:  Understanding

 

44. Which of the following statements best describes how extremes of pH often disrupt the function of enzymes?

a.	They alter the monosaccharides associated with the enzyme.
b.	They alter the chemistry of the enzyme’s active site.
c.	They destroy the substrate of the reaction.
d.	They destroy the products of the reaction.

 

 

ANS:  B                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6 | 5.7

MSC:  Understanding

 

45. Which of the following conditions destroys the three-dimensional structure of proteins?

a.	cold temperatures	c.	the presence of cofactors
b.	freezing the substrate	d.	very high salt concentrations

 

 

ANS:  D                    DIF:    Easy               REF:   5.3                 OBJ:   5.6 | 5.7

MSC:  Understanding

 

46. Which of the following strategies is NOT used by cells to help enzymes and substrates find each other?

a.	locating enzymes that are used in the same biochemical pathway close to each other in the cell
b.	having certain reactions occur within a specific organelle
c.	embedding enzymes in a membrane in a precise order
d.	producing heat to increase the frequency of molecular collisions

 

 

ANS:  D                    DIF:    Difficult         REF:   5.4                 OBJ:   5.4 | 5.6 | 5.8

MSC:  Understanding

 

47. In many organelles, groups of different enzymes are located on membranes in close proximity to each other. Why?

a.	Attaching enzymes to the membrane prevents the cell from losing them to the surrounding environment.
b.	When enzymes are in close proximity, each one can catalyze more than one type of reaction.
c.	These enzymes are involved in the same metabolic pathway; keeping them closer together increases the pathway’s efficiency.
d.	All enzymes must act in groups to sufficiently reduce the amount of activation energy needed for a reaction to occur.

 

 

ANS:  C                    DIF:    Moderate       REF:   5.4                 OBJ:   5.4 | 5.6 | 5.8

MSC:  Understanding

 

48. The sequential reaction pathway A ® B ® C ® D is dependent on enzymes for each separate step. If the pathway starts with A, how many different enzymes would be needed to produce D?

a.	just one, used over and over for each step
b.	two: one for the conversion of A to B and one for the conversion of C to D
c.	three
d.	four

 

 

ANS:  C                    DIF:    Moderate       REF:   5.4                 OBJ:   5.4 | 5.8

MSC:  Understanding

 

In this figure, E1, E2, and E3 represent three enzymes in the membrane of a mitochondrion. Based on the information in the figure, which of the following statements is true?

a.	B is the product of the activity of E2 and the substrate of E3.
b.	If E2 does not function properly, A will not be produced.
c.	E2 is the product of E1 and the substrate of E3.
d.	C is the substrate of E1.

 

 

ANS:  A                    DIF:    Moderate       REF:   5.4                 OBJ:   5.4 | 5.8

MSC:  Applying

 

50. Comparative studies have repeatedly shown that smaller animals have faster metabolic rates than larger animals. However, human males are larger than human females, yet men have a higher average basal metabolic rate (BMR) than women. Which of the following statements explains this variation in the pattern?

a.	Men typically weigh more than women; when standardized for body weight, the average BMR is identical for both genders.
b.	The large average body size of men reduces the ratio of surface area to volume; body systems elevate their metabolic rates to compensate for the change.
c.	Different tissues have different metabolic rates; the male body has a higher percentage of energy-consuming muscle than the female body.
d.	Compared with women, men have larger digestive systems, ingest more food per meal, and metabolize food at a higher rate to maintain body weight homeostasis.

 

 

ANS:  C                    DIF:    Easy               REF:   Applying What We Learned

OBJ:   5.3                 MSC:  Applying

 

51. The application of modern biological research methods has shown that the most successful strategy for permanent weight loss almost always involves

a.	simply eating less and exercising more.
b.	consuming BMR activators (supplements that elevate the basal metabolic rate), such as caffeine.
c.	changes in body composition, particularly changing connective tissue to muscle.
d.	altering the body’s ratio of surface area to volume.

 

 

ANS:  A                    DIF:    Moderate       REF:   Applying What We Learned

OBJ:   5.3 | 5.5          MSC:  Applying

 

52. A calorie represents the

a.	number of grams of fat in a food product.
b.	number of times an enzyme can be reused before it must be replaced.
c.	amount of energy needed to raise the temperature of one liter of water by 1°C.
d.	temperature at which a gram of food is completely converted into carbon dioxide.

 

 

ANS:  C                    DIF:    Easy               REF:   Applying What We Learned

OBJ:   5.1                 MSC:  Remembering

 

53. In a research study, physiologists monitored the metabolite concentrations generated during exercise in three groups of participants (people with poor fitness, average fitness, and exceptional fitness). Which statement best summarizes this study’s findings?

a.	Exercise was beneficial to all three groups, but those benefits ended immediately after the exercise stopped; to have significant benefits, exercise must be done for a longer period of time.
b.	The least fit participants had extremely low metabolic responsiveness; therefore, people with poor fitness are unlikely to experience benefits from exercise for at least 30 days after starting an exercise program.
c.	In all three groups, exercise produced an almost immediate positive metabolic effect in which the strength of the effect was proportional to the participants’ fitness levels.
d.	Metabolites extracted from the blood of the least fit participants suppressed the metabolism level of cells growing in a tissue culture.

 

 

ANS:  C                    DIF:    Difficult         REF:   Applying What We Learned

OBJ:   5.3 | 5.4 | 5.8   MSC:  Applying

 

54. If provided with the proper conditions, enzymes that are recovered from living tissues can be used in cell-free industrial processes. Which of the following statements is an example of such a process?

a.	The addition of amylases, lipases, and proteases can improve a detergent’s ability to remove wrinkles from clothing.
b.	Cellulases and pectinases can digest the proteins in fruit juice, producing a clarified product that is more appealing to consumers.
c.	The proteases in pineapples and papayas can tenderize meat by digesting its large fibrous proteins, such as collagen.
d.	Rennin, an enzyme from the guts of cows and sheep, has been used for many years to make pasta.

 

 

ANS:  C                    DIF:    Easy               REF:   Biology Matters

OBJ:   5.4 | 5.6 | 5.8   MSC:  Remembering

 

55. Which of the following organisms is NOT an ectotherm?

a.	a snake	c.	most insects
b.	a lizard	d.	a skunk

 

 

ANS:  D                    DIF:    Difficult         REF:   Biology in the News

OBJ:   5.3                 MSC:  Understanding

 

COMPLETION

 

1. A rotted log exemplifies the operation of the ________ law of thermodynamics.

 

ANS:  second

 

DIF:    Moderate        REF:   5.1                 OBJ:   5.1                 MSC:  Applying

 

2. When chemical energy is converted into kinetic energy in a biological system, ________ of the available energy is converted.

 

ANS:  less than all

 

DIF:    Moderate        REF:   5.1                 OBJ:   5.1                 MSC:  Understanding

 

3. When a molecule of methane burns, it produces carbon dioxide, heat, light, and water. The direction of the event is dictated by the ________ law of thermodynamics.

 

ANS:  second

 

DIF:    Difficult         REF:   5.1                 OBJ:   5.1                 MSC:  Applying

 

4. The capture and use of energy by living organisms involves many chemical reactions. Collectively, these processes are known as ________.

 

ANS:  metabolism

 

DIF:    Easy               REF:   5.2                 OBJ:   5.3                 MSC:  Remembering

 

5. Carbon dioxide is one product of a metabolic process that occurs in both plants and animals; this process is called ________.

 

ANS:  cellular respiration

 

DIF:    Easy               REF:   5.2                 OBJ:   5.2 | 5.3          MSC:  Remembering

 

6. Catabolic reactions are tightly coupled to reactions that require energy; those reactions are called ________ reactions.

 

ANS:

anabolic

biosynthetic

 

DIF:    Moderate        REF:   5.2                 OBJ:   5.3 | 5.5          MSC:  Remembering

 

7. The gain of electrons by one atom from another atom is referred to as ________.

 

ANS:  reduction

 

DIF:    Moderate        REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5   MSC:  Remembering

 

8. The energy input needed to start a chemical reaction is called the ________.

 

ANS:  activation energy

 

DIF:    Easy               REF:   5.3                 OBJ:   5.1 | 5.6          MSC:  Remembering

 

9. Almost all the chemical reactions that occur in cells are catalyzed by ________.

 

ANS:  enzymes

 

DIF:    Easy               REF:   5.3                 OBJ:   5.4 | 5.6 | 5.8   MSC:  Remembering

 

10. A catalyst is not changed during a chemical reaction, but it affects the ________ at which the reaction occurs.

 

ANS:

rate

speed

 

DIF:    Easy               REF:   5.3                 OBJ:   5.6                 MSC:  Remembering

 

11. In an enzyme, the area that has a specialized shape and/or set of chemical properties that enables the enzyme to bind to a particular substrate is called a(n) ________.

 

ANS:  active site

 

DIF:    Moderate        REF:   5.3                 OBJ:   5.6                 MSC:  Remembering

 

12. According to the ________ model, an enzyme’s active site will adjust its shape to mold around a substrate after binding to that substrate.

 

ANS:  induced fit

 

DIF:    Moderate        REF:   5.3                 OBJ:   5.6                 MSC:  Remembering

 

13. High temperatures generally cause the three-dimensional configuration of most enzymes to be destroyed. Enzymes that have been affected by high temperatures in this way have been ________.

 

ANS:  denatured

 

DIF:    Moderate        REF:   5.3                 OBJ:   5.6 | 5.7          MSC:  Remembering

 

14. Some enzymes need particular ions or small molecules to attain their highest activity; these enzyme “helpers” are known as ________.

 

ANS:  cofactors

 

DIF:    Moderate        REF:   5.3                 OBJ:   5.6 | 5.7          MSC:  Remembering

 

15. The enzyme maltase splits the disaccharide maltose into two sugar monomers. Maltose is maltase’s ________.

 

ANS:  substrate

 

DIF:    Moderate        REF:   5.3                 OBJ:   5.6                 MSC:  Applying

 

16. The organelles where the breakdown products of food are oxidized, generating most of a cell’s ATP, are called ________.

 

ANS:  mitochondria

 

DIF:    Easy               REF:   5.4                 OBJ:   5.3                 MSC:  Remembering

 

17. In a study, researchers put human participants on a treadmill for 10 minutes and then drew blood samples. They found that blood levels of certain “exercise metabolites” increased after the participants exercised. When the researchers added these “exercise metabolites” to mouse muscle cells cultured in a lab dish, the cells increased the rate at which they were burning ________.

 

ANS:  fat

 

DIF:    Moderate        REF:   Applying What We Learned            OBJ:   5.3

MSC:  Applying

 

18. Organisms that drop their basal metabolic rate (BMR) as cold weather arrives, enabling their body temperature to plummet, are called ________.

 

ANS:  hibernators

 

DIF:    Moderate        REF:   Biology in the News                        OBJ:   5.3

MSC:  Remembering

 

19. The tiny dwarf lemur balances its energy budget by ________ and ________ by burrowing underground.

 

ANS:

dropping its BMR, dropping its basal metabolic rate, minimizing heat loss

dropping its BMR, minimizing heat loss

dropping its basal metabolic rate, minimizing heat loss

minimizing heat loss, dropping its BMR

minimizing heat loss, dropping its basal metabolic rate

 

DIF:    Moderate        REF:   Biology in the News                        OBJ:   5.3

MSC:  Remembering

 

TRUE/FALSE

 

1. The first law of thermodynamics states that the total energy of a living system and its surroundings remains constant.

 

ANS:  T                    DIF:    Easy               REF:   5.1                 OBJ:   5.1

MSC:  Remembering

 

2. An insect devouring a leaf is an example of the second law of thermodynamics in action.

 

ANS:  T                    DIF:    Difficult         REF:   5.1                 OBJ:   5.1

MSC:  Applying

 

3. Photosynthesis creates energy; cellular respiration destroys energy.

 

ANS:  F                    DIF:    Moderate       REF:   5.1 | 5.2          OBJ:   5.1 | 5.2 | 5.3 | 5.5

MSC:  Remembering

 

4. During a chemical reaction, a cell uses all the chemical energy in ATP.

 

ANS:  F                    DIF:    Moderate       REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5

MSC:  Understanding

 

5. When ATP breaks down into ADP and a free phosphate group, energy is given off.

 

ANS:  T                    DIF:    Easy               REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5

MSC:  Remembering

 

6. As a molecule becomes oxidized, it loses electrons.

 

ANS:  T                    DIF:    Moderate       REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5

MSC:  Remembering

 

7. Oxygen can be reduced.

 

ANS:  T                    DIF:    Moderate       REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5

MSC:  Understanding

 

8. Sugar molecules are more oxidized than carbon dioxide molecules.

 

ANS:  F                    DIF:    Difficult         REF:   5.2                 OBJ:   5.1 | 5.2 | 5.3 | 5.5

MSC:  Applying

 

9. Chemical reactions in which reactants have a lower energy content than the products can occur without the input of any energy.

 

ANS:  F                    DIF:    Moderate       REF:   5.2                 OBJ:   5.1 | 5.3 | 5.5

MSC:  Understanding

 

10. Enzymes catalyze only anabolic chemical reactions.

 

ANS:  F                    DIF:    Moderate       REF:   5.3                 OBJ:   5.3 | 5.4 | 5.5 | 5.6 | 5.8

MSC:  Remembering

 

11. Enzymes can make reactions happen that would otherwise be impossible.

 

ANS:  F                    DIF:    Moderate       REF:   5.3                 OBJ:   5.1 | 5.6

MSC:  Understanding

 

12. The shape of an enzyme does not affect its activity.

 

ANS:  F                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6 | 5.7

MSC:  Understanding

 

13. At very high salt concentrations, the three-dimensional structure of proteins is often stabilized; therefore, these salt concentrations play a major role in enhancing the activity of many enzymes.

 

ANS:  F                    DIF:    Moderate       REF:   5.3                 OBJ:   5.6 | 5.7

MSC:  Understanding

 

14. In a metabolic pathway, the product of an enzyme-catalyzed reaction becomes the substrate for the next reaction in the pathway.

 

ANS:  T                    DIF:    Moderate       REF:   5.4                 OBJ:   5.3 | 5.4 | 5.8

MSC:  Remembering

 

15. The compartmentalization inside the mitochondrion improves the efficiency of the ATP production pathway by concentrating the reacting molecules.

 

ANS:  T                    DIF:    Moderate       REF:   5.4                 OBJ:   5.3 | 5.4 | 5.8

MSC:  Applying

 

16. Metabolic pathways are relatively uncommon in cells; most biologically significant molecules are obtained intact from a well-balanced diet.

 

ANS:  F                    DIF:    Moderate       REF:   5.4                 OBJ:   5.3 | 5.4 | 5.5 | 5.8

MSC:  Applying

 

17. Recent studies on weight loss have shown that without a rigorous training regimen, exercising muscle will preferentially burn carbohydrates rather than fat; these findings provide support for the observation that exercise alone is ineffective in promoting weight loss.

 

ANS:  F                    DIF:    Moderate       REF:   Applying What We Learned

OBJ:   5.3 | 5.5          MSC:  Applying