Biology Practice 3 test

In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of ________. A.ATP, CO2, and ethanol (ethyl alcohol) B.ATP, CO2, and lactate C.ATP, NADH, and pyruvate D.ATP, pyruvate, and oxygenE.ATP, pyruvate, and acetyl CoA

.ATP, CO2, and ethanol (ethyl alcohol)

In eukaryotes, photosynthesis takes place inside the ________. A.chloroplasts B.mitochondria C.cytoplasm D.Golgi apparatus

.mitochondria

Carbon dioxide (CO2) is released during which of the following stages of cellular respiration? A.glycolysis and the oxidation of pyruvate to acetyl CoA B.oxidation of pyruvate to acetyl CoA and the citric acid cycle C.the citric acid cycle and oxidative phosphorylation D.oxidative phosphorylation and fermentation E.fermentation and glycolysis

.oxidation of pyruvate to acetyl CoA and the citric acid cycle

When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton), the NAD+ molecule becomes A.dehydrogenated. B.oxidized. C.reduced. D.redoxed. E.hydrolyzed.

.reduced.

Which of the following events takes place in the electron transport chain? A.the breakdown ofglucose into two pyruvate molecules B.the breakdown of an acetyl group to carbon dioxide C.the extraction of energy from high-energy electrons remaining from glycolysis and the citric acid cycle D.substrate-level phosphorylation

.the extraction of energy from high-energy electrons remaining from glycolysis and the citric acid cycle

What is the main purpose of light-dependent reactions of photosynthesis? A.to generate oxygen by "splitting" H2O B.to produce NADPH for use in respiration C.to produce NADPH and ATP D.to use ATP to make glucose

.to produce NADPH and ATP

Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed by the reactions of glycolysis? A.0 percent B.2 percent C.10 percent D.38 percent E.100 percent

100 percent

How many carbon atoms are fed into the citric acid cycle as a result ofthe oxidation of one molecule of pyruvate? A.2 B.4 C.6 D.8 E.10

2

In the light-independent reactions, when CO2 is added to a molecule of Ribulose 1,5-bisphosphate (RuBP) the product is: A.citric acid. B.glucose. C.glyceraldehyde-3-phosphate. D.3-phosphoglycerate. E.pyruvate.

3-phosphoglycerate.

The complete oxidation of glucose (C6H12O6) to carbon dioxide and water in aerobic respiration consumes how many molecules of oxygen (O2)? A.1 B.3 C.6 D.12 E.36

6

in order to generate one glucose molecule, the Calvin cycle has to turn how many times? A.1 B.2 C.3 D.6 E.12

6

Approximately how many molecules of ATP are produced from the complete oxidation of two molecules of glucose (C6H12O6) in aerobic cellular respiration? A.2 B.4 C.15 D.30-32 E.60-64

60-64

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? A.CO2 and glucose B.H2O and O2 C.ADP, i, and NADP+ D.electrons and H+ E.ATP and NADPH

ATP and NADPH

Which of the following organisms have the greatest problem with photorespiration? A.C4 plants B.heterotrophs C.C3 plants D.CAM plants E.purple sulfur bacteria

C3 plants

Which of the listed statements describes the results of the following reaction?C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy A.C6H12O6 is oxidized and O2 is reduced. B.O2 is oxidizedand H2O is reduced. C.CO2 is reduced and O2 is oxidized. D.C6H12O6 is reduced and CO2 is oxidized.E.O2 is reduced and CO2 is oxidized.

C6H12O6 is oxidized and O2 is reduced.

The final product of the Calvin cycle is A.RuPB B.PGA C.ATP D.G3P

G3P

When oxygen is unavailable during heavy exercise what process do muscle cells use for energy generation? A.Glycolysis coupled with alcohol fermentation B.Anaerobic respiration C.Aerobic respiration D.Glycolysis coupled with lactate fermentation

Glycolysis coupled with lactate fermentation

Which of the following sequences correctly represents the flow of electrons during photosynthesis? A.NADPH → O2 → CO2 B.H2O → NADPH → Calvin cycle C.NADPH → chlorophyll → Calvin cycle D.H2O → photosystem I → photosystem II E.NADPH → electron transport chain → O2

H2O → NADPH → Calvin cycle

Hydrolysis of ATP releases energy, which results in the production of ADP and inorganic phosphate. What is commonly the ultimate fate of inorganic phosphate produced in the cytosol? A.It is secreted as waste. B.It is combined with ADP to regenerate ATP. C.It is phosphorylated. D.It is hydrolyzed to release additional energy.

It is combined with ADP to regenerate ATP.

As electrons are passed through the system of electron carriers associated with photosystem II, they lose energy. What happens to this energy? A.It excites electrons of the reaction center of photosystem I. B.It is lost as heat. C.It is used to establish and maintain a proton gradient .D.It is used to phosphorylate NAD+ to NADPH, the molecule that accepts electrons from photosystem I.

It is used to establish and maintain a proton gradient

Which of the events listed below occurs in the light reactions of photosynthesis? A.NADP is produced. B.NADPH is reduced to NADP+. C.Carbon dioxide is incorporated into PGA. D.ATP is phosphorylated to yield ADP. E.Light is absorbed and funneled to reaction-center chlorophyll a.

Light is absorbed and funneled to reaction-center chlorophyll a.

Which of the following statements about NAD+ is TRUE? A.NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. B.NAD+ has more chemical energy than NADH. C.NAD+ is oxidized by the action of hydrogenates. D.NAD+ can donate electrons for use in oxidative phosphorylation. E.In the absence of NAD+, glycolysis can still function.

NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and thecitric acid cycle.

following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO2 with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is in the form of ________. A.acetyl CoA B.glucose C.pyruvate D.NADH

NADH

Which electron carrier(s) function in the citric acid cycle? A.NAD+ only B.NADH and FADH2 C.the electron transport chain D.ADP and ATP

NADH and FADH2

In addition to ATP, what are the end products of glycolysis? A.CO2 and H2O B.CO2 and pyruvate C.NADH and pyruvate D.CO2 and NADHE.H2O, FADH2, and citrate

NADH and pyruvate

The light-independent reactions of plants function to make organic molecules using carbon dioxide as a carbon source. What is the electron source that helps reduce carbon dioxide to sugars and other organic molecules? A.NADH B.NADPH C.ATP D.electrons from oxygen

NADPH

in green plants, which photosystem absorbs photons to excite electrons in the reaction center? A.Photosystem I B.Photosystem II C.Photosystem III D.Photosystem I and II E.Photosystem I, II and III

Photosystem I and II

Matt is studying how the protein transferrin enters cells. He examines cells that have taken up transferrin (a protein), and finds clathrin-coated vesicles. What mechanism was used to take transferrin into the cell? A.Phagocytosis B.Pinocytosis C.Exocytosis D.Receptor-mediator endocytosis

Receptor-mediator endocytosis

In the light-independent reactions of photosynthesis, CO2 is added to a five-carbon molecule known as: A.cellulose. B.ribose. C.deoxyribose. D.RuBP. E.CAM.

RuBP

How are the light-dependent and light-independent reactions of photosynthesis related? A.The products of light-independent reactions are used in light-dependentreactions. B.The products of light-dependent reactions are used in light-independent reactions. C.The products of light-independent reactions must be present for light-dependent reactions to take place. D.They are not related.

The products of light-dependent reactions are used in light-independent reactions.

The energy of electron transport serves to move (translocate) protons to the outer mitochondrial compartment. How does this help the mitochondrion produce ATP? A.The hydrogen ions (protons) are transferred to oxygen in an energy-releasing reaction .B.The translocation of protons sets up the electrochemical gradient that drives ATP synthesis in the mitochondria. C.The protons pick up electrons from the electron transport chain on their way through the inner mitochondrial membrane. D.The protons receive electrons from the NAD+ and FAD that are accepted by electrons in glycolysis and the citric acid cycle.

The translocation of protons sets up the electrochemical gradient that drives ATP synthesis in the mitochondria.

Rubisco: A.catalyzes the carboxylation of CO2 to ribulose 1,5-bisphosphate. B.initiates photorespiration when the CO2/O2 ratio is low. C.catalyzes the reduction of two molecules of PGA to form glucose. D.all of the above (a-c). E.a and b, but not c.

a and b, but not c.

Carotenoids are important to many plants because these pigments are able to: A.remove carbon dioxide from the air. B.absorb wavelengths of light that neither chlorophyll a nor b can absorb. C.absorb water so that hydrolysis can be carried out in the chloroplasts. D.capture UV radiation that is harmful to the DNA in the nucleus of plant cells. E.store electrons for use during the "dark" reaction of photosynthesis.

absorb wavelengths of light that neither chlorophyll a nor b can absorb.

The oxygen consumed during cellular respiration is involved directly in which process or event?A.glycolysis B.accepting electrons at the end of the electron transport chain C.the citric acid cycle D.the oxidation of pyruvate to acetyl CoA E.the phosphorylation of ADP to form ATP

accepting electrons at the end of the electron transport chain

Chlorophylls absorb most light in which colors of the visible range? A.green and blue B.blue and red C.green and red D.violet and red

blue and red

At night, the Calvin cycle: A.cannot run, as it requires light energy directly B.can still run as long as there is ATP, CO2, and NADPH present C.runs in a different place in the plant D.uses a different source of carbon

can still run as long as there is ATP, CO2, and NADPH present

The role of the antenna complex in a photosystem is to: A.transfer excited electrons to the primary electron acceptor. B.generate glucose. C.generate NADPH. D.capture photons from sunlight.

capture photons from sunlight.

Where do the carbon atoms in glucose come from? A.Sunlight B.Carbon dioxide C.Water D.NADPH

carbon dioxide

In autumn, the leaves of deciduous trees change colors. This is because chlorophyll is degraded and ________. A.carotenoids and other pigments are still present in the leaves B.the degraded chlorophyll changes into many other colors C.water supply to the leaves has been reduced D.sugars are sent to most of the cells of the leaves

carotenoids and other pigments are still present in the leaves

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?A.anabolic pathways B.catabolic pathways C.fermentation pathways D.thermodynamic pathwaysE.bioenergetic pathways

catabolic pathways

Inside an active mitochondrion, most electrons follow which pathway? A.glycolysis → NADH → oxidative phosphorylation → ATP → oxygen B.citric acid cycle → FADH2 → electron transport chain → ATP C.electron transport chain → citric acid cycle → ATP → oxygen D.pyruvate → citric acid cycle → ATP → NADH → oxygen E.citric acid cycle → NADH → electron transport chain → oxygen

citric acid cycle → NADH → electron transport chain → oxygen

Oxidation and reduction reactions are chemical processes that result in a gain or loss of: A.atoms. B.neutrons. C.electrons. 'D.molecules. E.protons.

electrons

in chemiosmosis, what is the most direct source of energy that is used to convert ADP + Pi to ATP? A.energy released as electrons flow through the electron transport system B.energy released from substrate-level phosphorylation C.energy released from dehydration synthesis reactions D.energy released from movement of protons down their electrochemical gradient through ATP synthase

energy released from movement of protons down their electrochemical gradient through ATP synthase

Which of the following occurs in the cytosol of a eukaryotic cell? A.glycolysis and fermentation B.fermentation and chemiosmosis C.oxidation of pyruvate to acetyl CoA D.citric acid cycleE.oxidative phosphorylation

fermentation and chemiosmosis

CAM plants keep stomata closed in the daytime, thus reducing loss of water. They can do thisbecause they ________. A.fix CO2 into organic acids during the night B.fix CO2 into sugars in the bundle-sheath cells C.fix CO2 into pyruvate in the mesophyll cells D.use the enzyme phosphofructokinase, which outcompetes rubisco for CO2 E.use photosystem I and photosystem II at night

fix CO2 into organic acids during the night

.Photorespiration ________. A.generates carbon dioxide and consumes ATP and oxygen B.generates ATP and sugars and consumes oxygen and carbon dioxide C.generates oxygen and consumes ATP, carbon dioxide, and sugars D.consumes carbon dioxide and generates ATP, sugars, and oxygen

generates carbon dioxide and consumes ATP and oxygen

Which process in eukaryoticcells will proceed normally whether oxygen (O2) is present or absent?A.electron transport B.glycolysis C.the citric acid cycle D.oxidative phosphorylation E.chemiosmosis

glycolysis

Whichprocess in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?A.electron transport B.glycolysis C.the citric acid cycle D.oxidative phosphorylation E.chemiosmosis

glycolysis

In photosynthesis, carbon fixation occurs: A.in photosystem I B.in the electron transport chain C.in photosystem II D.in the Calvin cycle E.during photorespiration

in the Calvin cycle

Where are the proteins of the electron transport chain located? A.cytosol B.outer mitochondrial membrane C.inner mitochondrial membrane D.mitochondrial inter membrane space E.mitochondrial matrix

inner mitochondrial membrane

Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells? A.cytosol B.mitochondrial outer membrane C.mitochondrial inner membrane D.mitochondrial inter membrane space E.mitochondrial matrix

mitochondrial inter membrane space

During cellular respiration, acetyl CoA accumulates in which location? A.cytosol B.mitochondrial outer membrane C.mitochondrial inner membrane D.mitochondrial inter membrane space E.mitochondrial matrix

mitochondrial matrix

Which of the following produces the most ATP when glucose (C6H12O6) is completely oxidized to carbon dioxide (CO2) and water? A.glycolysis B.oxidation of pyruvate to acetyl CoA C.citric acid cycle D.oxidative phosphorylation (chemiosmosis)

oxidative phosphorylation (chemiosmosis)

When an atom or molecule gains one or more electrons, it is said to be: A.energized. B.oxidized. C.polarized. D.reduced.

reduced

When oxygen is released as a result of photosynthesis, it is a direct by-product of ________. A.reducing NADP+ B.splitting water molecules C. chemiosmosis D.the electron transfer system of photosystem I E.the electron transfer system of photosystem II

splitting water molecules

When oxygen is released as a result of photosynthesis, it is a direct by-product of________. A.reducing NADP+ B.splitting water molecules C .chemiosmosis D.the electron transfer system of photosystem I E.the electron transfer system of photosystem II

splitting water molecules

Where do the enzymatic reactions of the Calvin cycle take place? A. stroma of the chloroplast B.thylakoid membranes C.matrix of the mitochondria D.cytosol around the chloroplastE.thylakoid space

stroma of the chloroplast

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will most directly affect the ________. A.splitting of water B.absorption of light energy by chlorophyll C.flow of electrons from photosystem II to photosystem I D.synthesis of ATP E.reduction of NADP+

synthesis of ATP

.What is the primary function of the Calvin cycle?A.using ATP to release carbon dioxide B.using NADPH to release carbon dioxide C.splitting water and releasing oxygen D.transporting RuBP out of the chloroplast E.synthesizing simple sugars from carbon dioxide

synthesizing simple sugars from carbon dioxide

If the gene encoding the enzyme rubisco is mutated such that it is non-functional, the process that would be affected is A.the ability to make ATP. B.the ability to harvest photons. C.the ability to fix carbon. D.the ability to make O2. E.The ability to makeNADPH.

the ability to fix carbon.

As electrons travel from the primary electron acceptor in photosystem II, down the electron transport chain to photosystem I, they drive the movement of protons from the stroma into the thylakoid compartment. Why is the development of this chemical gradient useful to photosynthesis? A.protons are directly used in the thylakoid to make glucose B.protons provide the energy needed to drive the light-dependent reactions C.the proton gradient can drive the production of ATP, which is needed for the light-independent reactions D.this proton gradient is used to make NADPH, which is needed for the Calvin cycle

the proton gradient can drive the production of ATP, which is needed for the light-independent reactions

Why are fermentation reactions important for cells?A.They produce alcohol, which enhances the permeability of their mitochondrial membranes to proton translocation. B.They regenerate NAD+ so that glycolysis can continue to operate. C.They allow the cell to conserve oxygen for the citric acid cycle. D.They generate oxygen.

they regenerate NAD+ so that glycolysis can continue to operate.

Flattened sacs of internal membranes associated with photosynthesis are called: A.chloroplasts. B.photosystems. C.the stroma. D.thylakoids. E.cristae.

thylakoids.

in glycolysis, for eachmolecule of glucose oxidized to pyruvate ________. A.two molecules of ATP are used and two molecules of ATP are produced. B.two molecules of ATP are used and four molecules of ATP are produced. C.four molecules of ATP are used and two molecules of ATP are produced. D.two molecules of ATP are used and six molecules of ATP are produced.E.six molecules of ATP are used and six molecules of ATP are produced.

two molecules of ATP are used and four molecules of ATP are produced.

The electrons of photosystem II are excited and transferred to electron carriers. From which molecule or structure do the photosystem II replacement electrons come? A.the electron carrier, plastocyanin B.photosystem I C.water D.oxygen

water