BIO 121 Study Guide - Midterm Guide: Rna Splicing, Allosteric Regulation, Bacteriophage

1.When something appears blue, it is absorbing all colors except__________.

yellow

blue

red

green

orange

2.During heavy exercise, lactic acid can build up in ourmuscles. Why? How does this resemble the metabolism of bacteria andyeast?

lactic acid is results from insufficient oxygen during sugarmetabolism; it is fermentation

lactic acid accumulates when we are dehydrated; bacteria andyeast use the same pathway

lactic acid is built up from carbon dioxide; bacteria and yeaststore energy in this way

3.Why must a cell keep a similar concentration of dissolvedsubstances with the fluid surrounding them?

to avoid dilution of potential energy

to avoid osmotic imbalance and rapid gain or loss of water

to maintain the correct amount of dehydration and hydrolysis

4.What is entropy?

the amount of energy in a system

the amount of disorganization

the amount of organization

5.Burning a log is the reverse reaction found in photosynthesis.What products would be formed in burning a log?

carbon dioxide and water

glucose and oxygen

oxygen and carbon dioxide

oxygen and water

6.The main reason that cellular respiration needs to occur stepby step instead of a single, big reaction is

cells don't store enough oxygen

too much energy would be released for the cell to harness

cells don't have many mitochondria.

cells produce the enzymes needed for cellular respiration veryslowly

7.Enzymes are catalysts because they operate to:

raise activation energy

lower activation energy

supply activation energy

supply the reactants

8.When ATP powers a reaction it becomes ADP. The ADP

can reform ATP by an exergonic reaction

is a waste product for lysosomal breakdown

can reform ATP by an endergonic reaction

can reform ATP by an oxidation reaction

can reform ATP by an equilibrium reaction

9.The energy source that drives photosynthesis is

water

glucose

carbon dioxide

oxygen

sunlight

10. What is the process by which enzymes regulate their ownactivity?

osmosis

self-propulsion

feedback inhibition

11.Coupled reactions are reactions in which a

endergonic reaction drives a spontaneous reaction

exergonic reaction drives a spontaneous reaction

endergonic reaction drives an exergonic reaction

exergonic reaction drives an endergonic reaction

12.How is water used in photosynthesis?

as a substrate for ATP synthase

as an electron donor

to combine with ADP forming ATP

as an electron acceptor

13.Why are the “Dark Reactions” of photosynthesis referred to as“Dark”?

they do not require light

they can only occur at night

they generate excess sugar and the leaves turn brown

14.What is the difference between potential and kineticenergy?

potential is stored, kinetic is being used

potential is being used, kinetic is ready to be used

potential is negative, kinetic is positive

15.The products of cellular respiration are

carbon dioxide, water, and ATP

glucose, water, and ATP

glucose, carbon dioxide, and ATP

oxygen, ATP, and water

carbon dioxide, glucose, and water

16.All of the following are correct about energy except:

The biological world gets its energy from the sun.

Chemical bonds store potential energy.

A boulder perched on a hill has kinetic energy.

Energy is defined as the ability to do work.

All forms of energy can be converted to heat.

17.What is needed for the end product of glycolysis, pyruvate,to enter the citric acid cycle?

More glucose for energy

ATP

Oxygen

Carbon dioxide

18.The enzyme that forms a transmembrane channel in mitochondriaand phosphorylates ADP

a carrier protein

ATP synthase

acetyl CoA

19.Fermentation is most common in

plants

microorganisms

animals

20.During adsorption of sunlight by photosystems, H+ ions aregenerated. Where do they come from? What are they used for?

from the breakdown of sugar; they help form water

water; they help form sugar

from carbon dioxide; they help dissolve NaCl

21.Glycolysis

does not use oxygen

uses oxygen

uses carbon dioxide

22.Photosynthesis is

not dependent on chlorophyll

a process that produces glucose and oxygen

a process that produces water and carbon dioxide

23.Breakdown of glucose generates many ATP molecules, each ofwhich can be used independently. Why is ATP ideally suited to powerbiological reactions?

ATP has many hydrogen bonds

ATP has enough energy to power one biological reaction

ATP readily dissolves in water

24.Objects that are not actively moving but have the capacity todo so are said to possess:

kinetic energy

entropy

potential energy

living energy

25.The first stage of cellular respiration, called ___________,takes place in the cytoplasm of the cell and needs no oxygen.

photorespiration

citric acid cycle

glycolysis

oxidation

26.Diffusion

requires energy

utilizes proteins to move molecules across a membrane

moves molecules against a concentration gradient

does not require energy

cannot occur without a membrane present

27.What is the name of the molecule on which an enzymeworks?

substrate

monomer

polymer

28.ATP contains

phenylalanine

two phosphate groups

three nitrate groups

three phosphate groups

29.How does chlorophyll function in photosynthesis?

by absorbing carbon dioxide

by absorbing the sun's energy

by absorbing water

30.Objects that are moving are said to possess:

living energy

potential energy

entropy

kinetic energy

31.The respiration pathway that evolved first is probably

glycolysis

aerobic respiration

citric acid cycle

32.The energy source for the process of photosynthesis is

oxygen

sunlight

carbon dioxide

chlorophyll

glucose

33.Burning wood generates heat and light. What type of reactionis this?

exergonic

kinetic energy

endergonic

potential energy

equilibrium

34.What is meant by a “coupled reaction” in terms of energy?

many poymers are built simultaneously

energy released by one reactions powers another reaction

some reactions occur in the same organelle

35.The First Law of Thermodynamics states:

energy is constantly being created by entropy events

energy can be changed from one form to another, but cannot becreated or destroyed

energy can be used and then destroyed because of entropy'sactions on it

energy can be destroyed while it is producing entropy

36.How do we dispose of the carbon derived from the glucose thatis metabolized during respiration?

by breathing out

via our urine

it is broken down in lysosomes

37.Both plant and animal cells have mitochondria because theyboth

carry on respiration

carry on photosynthesis.

require water

38.What is Activation Energy?

the energy needed to initiate a reaction

the energy that transports water into cells

potential energy

39.If you put a plant in a chamber and shine a light on it

oxygen will decrease and carbon dioxide will increase

oxygen will increase and carbon dioxide will decrease

oxygen and carbon dioxide will increase

oxygen and carbon dioxide will decrease

40.What are the inputs and the output molecules for the overallphotosynthetic process?

input sugar and oxygen; output carbon dioxide and water

input oxygen and water; output sugar and carbon dioxide

input carbon dioxide and water;output sugar and oxygen

41.What kind of reaction is photosynthesis?

endergonic

kinetic energy

exergonic

potential energy

equilibrium

42.In the process of glycolysis, glucose is cleaved into a pairof three-carbon molecules called

lactate

pyruvate

acetyl CoA

ATP

alcohol

43.Entropy is

order

disorder

complexity

Both order and disorder are correct

Both complexity and disorder are correct

44.Glycolysis takes place in the _____________ and the citricacid cycle and electron transport chain take place in the___________.

cytoplasm; endoplasmic reticulum

mitochondria, chloroplast

mitochondria; cytoplasm

cytoplasm; mitochondria

45.The organelle that carries out photosynthesis in plants isthe

mitochondria

chloroplast

ribosome

chlorophylllysosome

46.The energy to power the Calvin cycle comes from

cellular respiration

oxygen

the light reactions of photosynthesis

47.Which of the following can be broken down into intermediateproducts that enter cellular respiration?

Proteins

Lipids

Carbohydrates

All of these.

48.When cellular product levels get too high, the responsibleenzyme is inhibited. This is an example of

promotion

denaturation

equilibrium

a coenzyme

feedback inhibition

49.How is respiration the opposite of photosynthesis?

respiration breaks sugar down to carbon dioxide; photosynthesisbuilds sugar from carbon dioxide

respiration builds sugar from carbon dioxide; photosynthesisbreaks sugar down to carbon dioxide

respiration requires energy input; photosynthesis gives offexcess energy

50.The molecule that absorbs sunlight for photosynthesis is

oxygen

carbon dioxide

chlorophyll

glucose

sunlight

A catabolic pathway would predictably result in the
A) reduction of a sugar.
B) synthesis of a macromolecule.
C) breakdown of a macromolecule.
D) breakdown of an atom.
2.
The drug Ritonavir is used to treat people with HIV/AIDS. It worksby binding to the active site of HIV-1 protease, an enzyme used bythe AIDS virus to create new proteins for production of newviruses.Once bound, the HIV-1 protease cannot produce proteins.Ritonavir can be classified as a(n)
A) competitive inhibitor.
B) allosteric inhibitor.
C) activator.
D) non-competitive inhibitor.
3.
During cellular respiration, __________ is the final electronacceptor that allows the regeneration of the cell’s supply of NAD+.In fermentation, ____________ is the final electron acceptor forNAD+ regeneration.
A) pyruvate / lactic acid
B) pyruvate / oxygen
C) ethanol / CO2
D) oxygen / pyruvate
4.
Which of the following clues would tell you if a cell isprokaryotic or eukaryotic?
A) whether or not the cell carries out cellular metabolism
B) the presence or absence of ribosomes
C) whether or not the cell is partitioned by internalmembranes
D) whether or not the cell contains DNA
5.
Phosphofructokinase (PFK) is an allosteric enzyme that regulatesglycolysis. When cellular concentrations of ATP and citrate become__________, this enzyme’s activity decreases. When cellularconcentrations of AMP become ________, the enzyme isactivated.
A) high / high
B) high / low
C) low / high
D) low / low
6.
______________ is an enzyme that can utilize the free energy in thehydrogen gradient (voltage) produced between the inner and outermembrane of the mitochondrion. The enzyme uses this energy toproduce ________.
A) ATP synthase/ ATP
B) PFK/ ATP
C) PFK/ glucose
D) ATP synthase/ ADP
7.
ATP is able to do cellular work because it
A) has a high energy phosphate bond that can be hydrolyzed torelease energy.
B) converts light energy into chemical bond energy.
C) contains the sugar ribose, which can provide additional energyfor a cell.
D) its hydrolysis is endergonic.
8.
A solution of starch at room temperature does not readily decomposeto form a solution of simple sugars because
A) the starch solution has less free energy than the sugarsolution.
B) the activation energy barrier for this reaction cannot besurmounted.
C) the hydrolysis of starch to sugar is endergonic.
D) starch hydrolysis is nonspontaneous.
9.
A person exposed to toxins would have more activity in their___________compared to an unexposed person.
A) lysosomes
B) Golgi bodies
C) rough endoplasmic reticulum
D) smooth endoplasmic reticulum
10.
Which of the following statements about fermentation is true?
A) The function of fermentation is to regenerate the fermentingcells' supply of NAD+.
B) Fermentation allows a fermenting cell to gain more energy perglucose molecule than a non-fermenting cell.
C) Fermentation produces either lactic acid or ethanol that thefermenting cell can use as an energy source.
D) Fermentation is a universal process that occurs in all cells andall organisms.
11.
A glucose molecule is completely broken down to carbon dioxide andwater in glycolysis and the citric acid (Krebs) cycle, but togetherthese two processes yield only a few molecules of ATP. Whathappened to most of the energy that the cell obtains from theoxidation of glucose?
A) It was lost as heat.
B) It is stored in the carbon dioxide and water molecules releasedby these processes.
C) It is stored in the ATP that was formed by glycolysis and thecitric acid cycle.
D) It is stored in NADH and FADH2
12.
The First Law of Thermodynamics states that
A) entropy tends to increase in a system.
B) entropy tends to decrease in a system.
C) energy cannot be created nor destroyed.
D) the quality of energy in the universe is decreasing.
13.
The endosymbiotic theory states that _______________ evolved as aresult of a symbiotic relationship between different types ofbacteria. _____________ is thought to be the selective factor thatmade this symbiosis advantageous.
A) mitochondria / A change in the Earth’s atmosphere from anaerobicto aerobic
B) endoplasmic reticulum / A decrease in the amount of foodavailable in the environment
C) chloroplasts / A change in the Earth’s atmosphere from aerobicto anaerobic
D) lysosomes / A decrease in the amount of food available in theenvironment
14.
A mutation in a fruit fly affects one of the proteins that pumphydrogen ions across the inner mitochondrial membrane; thismutation makes that particular protein function less efficiently.When comparing aerobic cellular respiration in this fly with awild-type fly, you would predict that the mutant fly would
A) produce less ATP than a wild-type fly.
B) show no difference in ATP production when compared to awild-type fly.
C) produce more ATP than a wild-type fly.
D) not be able to produce any ATP via aerobic cellularrespiration.
15.
Proteins that are destined to be exported from the cell have unique_________________ that are recognized by signal recognitionparticles and thus moved to the _________________ duringtranslation.
A) phosphofructokinases / nucleus
B) codons / rough endoplasmic reticulum
C) signal recognition sequences / rough endoplasmic reticulum
D) signal recognition sequences / free ribosomes
16.
During the Krebs cycle
A) NADH is oxidized.
B) ATP is produced.
C) pyruvate is produced.
D) Acetly CoA gains a carbon to form pyruvate.
17.
Why does the oxidation of organic compounds by molecular oxygen toproduce CO2 and water release free energy?
A) Electrons are being moved from atoms that have a lower affinityfor electrons (such as C) to atoms with a higher affinity forelectrons (such as O).
B) The electrons have a higher potential energy when associatedwith water and CO2 than they do in organic compounds.
C) The covalent bond in O2 is unstable and easily broken byelectrons from organic molecules.
D) The covalent bonds in organic molecules and molecular oxygenhave more kinetic energy than the covalent bonds in water andcarbon dioxide.
18.
In a chemical reaction, if ?G is negative, it means that thereaction is
A) exergonic, and work needs to be done for the reaction toproceed.
B) exergonic, and work can be done with energy released from thereaction.
C) endergonic, and work needs to be done in order for the reactionto proceed.
D) endergonic, and work can be done with energy released from thereaction.
19.
The energy for an endergonic reaction comes from a(n) ___________reaction.
A) ADP + P --> ATP
B) endergonic.
C) exergonic.
D) anabolic
20.
Glycolysis
A) involves catabolic reactions and ATP is produced.
B) involves anabolic reactions and ATP is produced.
C) involves catabolic reactions and creates energy.
D) involves anabolic reactions and creates energy.

1. C6H12O6 + 6O2 Ã 6CO2 + 6H2O Glucose is being _____ to _____ and oxygen is being _____ to _____. a. oxidized; carbon dioxide; reduced; water b. oxidized; water; reduced; carbon dioxide Incorrect c. reduced; water; oxidized; carbon dioxide d. reduced; carbon dioxide; oxidized; water

2. Which of the following stages in the breakdown of the piece of toast you had for breakfast generates the most ATP? a. the citric acid cycle Incorrect b. glycolysis c. the digestion of starch to glucose d. oxidative phosphorylation

3. Which of the following is a catabolic pathway? a. gluconeogenesis b. production of starch Incorrect c. glycolysis d. production of glycogen

4. Per molecule, the oxidation of a fatty acid results in _____ energy storage than the oxidation of glucose. a. the same b. less Incorrect c. more d. None of the above; fatty acids cannot be oxidized.

5. Of the eight reactions in the citric acid cycle, how many are oxidation-reduction reactions? a. one b. two c. three d. four e. five

6. The process of glycolysis transfers the energy in sugar molecules into the stored energy of activated carriers such as ATP and NADH. Which statement is true about glycolysis? a. Only eukaryotic organisms do glycolysis. b. The ten reactions of glycolysis are identical in all eukaryotic cells, but are different in prokaryotic cells due to their diverse metabolic strategies. Incorrect c. The ten reactions of glycolysis are identical in almost all living organisms on the planet. d. There are many ways to oxidize glucose and transfer energy into activated carriers; the diversity of organisms on the planet is reflected in the diversity of their mechanisms of glycolysis.

7. Referring to the sentence completed in #13 above, the purpose of the latter reaction (in active muscle cells) is to _____. a. accumulate lactic acid in the cell, which provides additional energy for the production of ATP Incorrect b. slow down glycolysis until oxygen becomes available again c. accelerate the Krebs cycle, which will restore the oxygen supply d. regenerate NAD+ so that glycolysis can continue in the absence of oxygen

8. What are the products of the citric acid cycle? a. carbon dioxide, NADH, FADH2 and GTP b. carbon dioxide, NAD+, FAD and GTP c. NADH, FADH2, and acetyl CoA Incorrect d. carbon dioxide and water

9. Which statement is true about enzymes? a. Enzymes catalyze chemical reactions because they make inherently endergonic reactions exergonic. b. Each enzyme in a cell can catalyze many different chemical reactions involving chemically different substrates. Incorrect c. Enzymes can only catalyze reactions in one direction. d. After catalyzing a reaction, an enzyme is permanently altered and can no longer bind substrate. e. None of the above is true. 1

10. ∆G measures the change in free energy in a system as it converts reactant (Y) into product (X). When [X] = [Y], ∆G is equal to _____. a. RT b. ΔG° + RT c. ΔG° d. ln [X]/[Y]

11. The ∆G° for the hydrolysis of ATP is -7.3 kcal/mol. What conditions in the cell would lead to a ∆G for ATP hydrolysis of -11 kcal/mol? a. An increase in the ATP/ADP ratio b. An increase in anabolic activity in the cell c. Transport of ATP out of the compartment where the reaction is occurring Incorrect d. A decrease in the ATP/ADP ratio

12. In the first reaction of glycolysis, a phosphate transferred from ATP to a glucose molecule to produce glucose-6-phosphate and ADP. Under conditions existing in the cell, the free energy change for this reaction is -8.0 kcal/mole. Which of the following statements is true? Recall that the ∆G° for the hydrolysis of ATP is -7.3 kcal/mol. a. Glucose concentrations in the cell are always low, making this reaction more favorable than would be expected. b. This reaction is less favorable than would be expected, given the ∆G° of ATP hydrolysis. c. Glucose-6-P concentrations in the cell are very low relative to glucose concentrations, making the reaction more favorable than would be expected. d. The ∆G° for the addition of a phosphate to glucose must be -0.7 kcal/mole.

13. Protein E can bind to two different proteins, S and I. The binding reactions are described by the following equations and values: E + S --> ES Keq for ES = 10 E + I> EI Keq for EI = 2 Given the equilibrium constant values, which one of the following statements is true? a. When S is present in excess, no I molecules will bind to E. b. E binds I more tightly than S. c. The binding energy of the ES interaction is greater than that of the EI interaction. d. Changing an amino acid on the binding surface of I from a basic amino acid to an acidic one will probably make the free energy of association with E more negative.