Exam 2 biol425
For each molecule of glucose that completes glycolysis, how many NAD+ molecules are reduced? a. 4 b. 3 c. 1 d. 0 e. 2
2
For every molecule of glucose that begins glycolosis, how many molecules of acetyl CoA are produced? a. 1 b. 4 c. 0 d. 2 e. 3
2
The preparatory phase of glycolosis involves: a. 2 molecules of ATP only b. 1 molecule of ATP and 1 molecule of NADH c. I molecule of ATP and 1 molecule of NAD+ d. 2 molecules of NADH only e. 2 molecules of NAD+ only
2 molecules of ATP only
Which of the following does NOT occur in the Calvin cycle? a. NADPH is oxidized b. ADP is phosphorylated to ATP c. Ribulose 1, 5-biphosphate is regenerated d. ATP is hydrolyzed e. CO2 is fixed
ADP is phosphorylated to ATP
Which of the following is produced during noncyclic AND cyclic electron flow? a. ATP b. water c. O2 d. sugar e. NADPH
ATP
Which of the following statements about CAM plants is FALSE? a. Their water-use efficiency is higher than that of C3 and C4 plants b. All CAM plants are flowering plants c. They are dependent on nighttime accumulation of CO2 for photosynthesis d. Not all CAM plants are succulent e. They use both C3 and C4 pathways
All CAM plants are flowering plants
Which of the following statements concerning glycolysis is FALSE? a. It is considered a primitive process b. It is an aerobic process c. It occurs in a series of 10 steps d. It is carried out by virtually all cells e. Its reactions are catalyzed by specific enzymes
It is an aerobic process
Which of the following statements about photorespiration is FALSE? a. It yields ATP but not NADPH b. it consumes oxygen and releases CO2 c. phosoglycolate is an intermediate d. three cellular organelles participate in the process e. it is a wasteful process
It yields ATP but not NADPH
Rubisco can use _______ or CO2 as a substrate. a. oxaloacetate b. 3-phosphoglycerate c. serine d. O2 e. glyceraldehyde 3-phosphate
O2
Which of the following statements about the redox reactions in the citric acid cycle is FALSE? a. NAD+ and FAD are reduced b. CO2 is released c. electrons go from higher to lower energy levels d. energy is released e. Oxygen molecule accepts electrons and gets reduced.
Oxygen molecule accepts electrons and gets reduced.
In photosystem II, energized electrons are transferred from pheophytin directly to: a. plastoquinol b. PQA c. the oxygen-evolving complex d. chlorophyll a e. NADP+
PQA
In the C4 pathway, the enzyme PEP carboxylase: a. is active only in the chloroplasts of mesophyll cells b. uses O2 as a substrate c. operates inefficiently when the CO2 concentration is low d. uses CO2 as a substrate e. catalyzes the formation of oxaloacetate
catalyzes the formation of oxaloacetate
Which pigment occurs in all photosynthetic eukaryotes? a. bacteriochlorophyll b. chlorophyll c c. chlorophyll b d. chlorobium chlorophyll e. chlorophyll a
chlorophyll a
In photophosphorylation, the role of the ATP synthase complex is to provide a channel for protons to flow back into the: a. intermembrane space of mitochondrion b. cytosol c. lumen of the thylakoid d. chloroplast stroma e. intermembrane space of chloroplast
chloroplast stroma
The ______ complex links photosystems I and II. a. water photolysis b. oxygen-evolving c. ATP synthase d. cyctochrome b6/f e. light-harvesting
cyctochrome b6/f
Which of the following is most likely to occur in a leaf of a CAM plant during the day? a. exit of water through stomata b. decarboxylation of malic acid c. conversion of oxaloacetate to malate d. entry of CO2 through stomata e. fixation of CO2 by PEP carboxylase
decarboxylation of malic acid
Photosystem I (PSI) and photosystem II (PSII) are spatially separated a. PS1 in the stroma and PS 2 in the grana lumen b. PS 2 in the stroma and PS 1 in the grana thylakoids c. PS 1 in the inner and PS 2 in the outer membrane d. PS 1 in the stroma thylakoids and PS 2 in the grana thylakoids e. PS 2 in the stroma thylakoids and PS 1 in the grana thylakoids
PS 1 in the stroma thylakoids and PS 2 in the grana thylakoids
Which of the following statements about the electromagnetic spectrum is FALSE? a. All radiations travel in waves. b. White light consists of a number of different colors c. A wavelength is the distance from one wave crest to the crest of another d. Different colors of light are refracted at different angles e. Purple light corresponds to a specific wavelength
Purple light corresponds to a specific wavelength
The malate or aspartate produced in the C4 pathway moves next into: a. the stomata b. Photosystem II c. Photosystem I d. a bundle-sheath cells e. the mesophyll cells
a bundle-sheath cells
Xanthyophylls and carotenes: a. are the principal photosynthetic pigments in green plants b. are carotenoids c. are the principle sources of vitamin C for humans d. are normally present in cytosol rather in plastids e. can substitute for chlorophylls in photosynthesis
are carotenoids
A regulatory enzyme in a metabolic pathway is most likely to be the: a. last enzyme in the pathway b. enzyme that binds its coenzyme fastest c. first enzyme in the pathway d. enzyme that lacks an effector site e.enzyme that catalyzes the fastest reaction in the pathway
first enzyme in the pathway
An enzyme: a. functions as a catalyst b. is typically effective only in large amounts c. raises the activation energy of its reaction d. is permanently altered during the course of its reaction e. is a type of carbohydrate
functions as a catalyst
The radiant energy of the sun is captured in the process of photosynthesis and at each energy conversion step some energy is lost, e.g. in the form of: a. kinetic energy b. entropy c. heat d. water potential e. potential energy
heat
Following photolysis, the resulting protons are released into the ______, contributing to the proton gradient across the ____ membrane. a. lumen of the thylakoid; thylakoid b. chloroplast matrix; inner chloroplast c. chloroplast stroma; outer chloroplast d. cytosol; inner mitochondrial e. chloroplast stroma; thylakoid
lumen of the thylakoid; thylakoid
Pyruvate is converted to acetyl CoA in the ______ of the _____. a. matrix; mitochondria b. cristae; mitochondria c. cytosol; cell d. lumen; smooth ER e. ribosomes; rough ER
matrix; mitochondria
Kranz anatomy is characterized by a layer of ______ around a layer of ______. a. bundle-sheath cells; pholem cells b. bundle-sheath cells; mesophyll cells c. mesophyll cells; pholem cells d. xylem cells; mesophyll cells e. mesophyll cells; bundle-sheath cells
mesophyll cells; bundle-sheath cells
Which of the following does NOT occur during the citric acid cycle? a. regeneration of oxaloacetate b. oxidative phosphorylation c. decarboxylation d. substrate-level phosphorylation e. oxidation
oxidative phosphorylation
One of the benefits of photorespiration is removing toxic: a. phosphoglycolate b. oxaloacetate c. 3-phosphoglycerate d. 3-phosophoglyceraldehyde e. ribulose-bisphosphate
phosphoglycolate
The addition of a phosphate group to a molecule is known as _________ and catalyzed by _______. a. dephosphorylation and kinases b. dehydration synthesis and water c. reduction and coenzymes d. oxidative phosphorylation e. phosphorylation and kinases
phosphorylation and kinases
Which of the following events is NOT associated with Photosystem I? a. chlororespiration b. absorption of light by antenna molecules c. reduction of NADP+ d. photolysis of water e. excitation of an electron from P700
photolysis of water
In the light reactions, the cytochrome b6/f complex recieves electrons directly from: a. ferredoxin b. plastocyanin c. phenophytin d. manganese e. plastoquinol
plastoquinol
Most enzymes are: a. proteins b. DNA molecules c. lipids d. RNA molecules e. carbohydrates
proteins
Oxidative phosphorylation depends on a gradient of ________ across the mitochondrial membrane. a. ADP b. phosphate c. protons d. electrons e. glucose
protons
The energy released by the flow of electrons along the electron transport chain is used directly to: a. reduce FAD b. form ATP from ADP and phosphate c. decarboxylate citrate d. oxidize NADH e. pump protons
pump protons
In glycolysis, one molecule of glucose is converted to _______ molecules of ______. a. two; pyruvate b. two; fructose c. three; fructose d. two; sucrose e. three; pyruvate
two; pyruvate
In CAM plants, malate formed as a the end product of C02 fixation in the dark is stored as malic acid in the: a. nucleus b. thylakoid lumen c. vacuole d. chloroplast stroma e. cytosol
vacuole
The oxygen gas is released in photosynthesis originates from: a. water b. sugar c. carbon dioxide d. nitrates e. ozone
water
Which of the following is not considered a CAM plant? a. wheat b. Spanish "moss" c. pineapple d. cactus e. Welwitchia
wheat
t/f All photosynthetic eukaryotes contain both chlorophylls a and b.
f
t/f At the reaction center of Photosystem II is P700.
f
t/f Chlorophyll absorbs light principally in the green wavelength.
f
t/f In a zygote, all genes are expressed at once.
f
t/f Photorespiration is an energetically wasteful process that seldom occurs in nature.
f
Under anaerobic conditions, yeasts and most plant cells convert pyruvate to: a. ethanol and carbon dioxide b. ATP c. glucose d. lactate e. acetyl CoA
lactate
Te energy-transduction reactions of photosynthesis are also called the _______. a. light b. carbon-fixation c. light-independent d. dark e. biosynthetic
light
The process of photosynthesis results in the formation of two substances essential to our existence: a. sugar and water b. sugar and oxygen c. chlorophyll and water d. electrons and protons e. chlorophyll and oxygen
sugar and oxygen
t/f A photosystem is a supramolecular complex in the thylakoid memebrane of chloroplasts of plants, a light harvesting antenna with a reaction center comprising of a pair of special chlorophyll-a molecules acting as redox electron carriers, oxidizing water and passing the high energy electron to an electron transport chain.
t
t/f ATP and NADPH are produced on the side facing the stroma, where the Calvin cycle takes place.
t
t/f Light reactions increase the potential energy of electrons by moving them from H20 to NADPH and generate ATP.
t
t/f More energy is obtained when glucose is oxidized under aerobic conditions rather than anaerobic conditions.
t
t/f One of the benefits of photorespiration is to remove phosphoglycolate from the plant.
t
t/f Rubisco can use either O2 or CO2 as a substrate.
t
t/f The ATP and NADPH generated by the light reactions are used in the Calvin cycle.
t
t/f The leaf anatomy of C4 plants provides a spatial separation between the C4 pathway and the Calvin cycle.
t
t/f The light-harvesting complex does not contain a reaction center.
t
t/f Under extremely dry conditions, CAM plants outcomplete C3 and C4 plants
t
The role of Rubisco is to catalyze the conversion of: a. CO2 to an unstable six-carbon compound b. CO2 to glyceraldehyde 3-phosphate c. glyceraldehyde 3-phosphate to sucrose d. glyceraldehyde 3-phosphate to starch e. 3-phosglycerate to glyceraldehyde 3-phosphate
CO2 to an unstable six-carbon compound
t/f In the process of cyclic photophosphorylation, both ATP and NADPH are produced.
F
t/f Protons flow through the ATP synthesis from the stroma into the thylakoid lumen.
F
t/f The concentration of CO2 in the Earth's atmosphere is approximately 3 percent.
F
t/f The energy of the photon of light is directly proportional to its wavelength.
F
t/f A photosystem is supramolecular complex in the thylakoid membrane of the chloroplasts of plants, a light harvesting antenna with a reaction center comprising of a pair of special chlorophyll-a molecules acting as redox electron carriers, oxidizing water and passing the high energy electron transport chain.
T
t/f An action spectrum can be used to demonstrate the relative effectiveness of different wavelengths of light for photosynthesis.
T
t/f An antenna (or light harvesting complex ) does not have a reaction center.
T
t/f In a metabolic pathway, there is little accumulation of intermediate products.
T
t/f In glycolysis, ATP is consumed in some reactions and produced in others.
T
t/f The photolysis of water occurs in conjunction with Photosystem II but not Photosystem I.
T
t/f Totipotency refers to the ability of an individual plant cell to grow into an entire plant
T
The electrochemical gradient resulting from electron transport is due to the differences in ________ across the inner mitochondrial membrane. a. electric charge and proton concentration b. ATP and NAD+ concentrations c. proton concentration only d. only the ATP concentration e. only the electric charge
electric charge and proton concentration
Most of the carriers of the electron transport chain are: a. embedded in the outer mitochondrial membrane. b. contained between the outer and inner mitochondrial membranes. c. in the mitochondrial matrix. d. in the cytosol. e. embedded in the inner mitochondrial membrane
embedded in the inner mitochondrial membrane
Which of the following does NOT occur during respiration? a. glycolysis b. electron transport chain c. formation of acetyl CoA d. citric acid cycle e. hydrolysis of starch to glucose
hydrolysis of starch to glucose
In contrast to Photosystem I, Photosytem II is located primarily: a. in the chloroplast b. in stroma thylakoids c. in the plasma membrane d. in grana thylakoids e. in the cytosol
in grana thylakoids
An action spectrum is different from an absorption spectrum in that an action spectrum: a. is the relative effectiveness of different wavelengths for a specific process b. is the light-transmitting pattern of a pigment c. is the light-absorbing pattern of a pigment d. provides evidence that a particular pigment is responsible for a particular process e. provides information about the extent of reflectance
is the relative effectiveness of different wavelengths for a specific process
Which of the following statements about an antenna complex is FALSE? a. it converts light energy into chemical energy b. it is part of a photosystem c. it contains chlorophyll molecules d. it "funnels" energy to the reaction center e. it contains carotenoid pigments
it converts light energy into chemical energy
The light-harvesting complex is different from a photosystem in that the light-harvesting complex: a. lacks chlorophyll a b. collects light energy c. contains pigment-binding proteins d. lacks a reaction center e. lacks carotenoids
lacks a reaction center
In respiration, most of the energy in the original glucose molecule is: a. stored in the molecules of ATP b. released as heat c. released in molecules of carbon dioxide d. stored in the molecules of pyruvate e. stored in the molecules of ADP
released as heat
In the antenna complex, light energy is transferred from one pigment molecule to another by: a. pigment activation b. resonance energy transfer c. reduction d. oxidation e. fluorescence
resonance energy transfer
Carbon dioxide is "fixed" by bonding to: a. ADP b. NADP+ c. glyceraldehyde 3-phosphate d. ribulose 1, 5-bisphosphate e. 3-phosphoglycerate
ribulose 1, 5-bisphosphate
Most of the glyceraldehyde 3-phosphate not exported to the cytosol is converted to _______ and stored in the chloroplasts. a. 3-phosphoglycerate b. sucrose c. starch d. glucose e. ribulose 1, 5-biphosphate
starch
The metabolic "hub" of the cell is: a. oxidative phosphorylation b. the citric acid cycle c. glycolysis d. the electric transport chain e. fermentation
the citric acid cycle
Where in the cell does glycolysis occur? a. the endoplastic reticulum b. mitochondria c. chloroplasts d. the nucleus e. the cytosol
the cytosol
Which of the following is the very next event that occurs when a chlorophyll molecule absorbs light? a. fluorescence occurs b. the energy is released as heat c. the electron is transferred to an electron transport chain d.resonance energy transfer occurs e. the electron is boosted to an excited state
the electron is boosted to an excited state
Most of the ATP formed in respiration is produced by reactions associated with: a. the electron transport chain b. glycolysis c. fermentation d. the citric acid cycle e. the conversion of pyruvate to acetyl CoA
the electron transport chain
During the cyclic electron flow, electrons are transferred directly from P700 to Ao to: a. the photosynthetic ATP synthase b. the lumen of the thylakoid c. P680 d. the photosynthetic electron transport chain e. P700
the photosynthetic electron transport chain
Chlorophylls and carotenoid pigments are embedded in the: a. stroma b. outer chloroplast membrane c. thylakoid membranes d. plasmalemma e. nucleoids
thylakoid membranes
Grana are stacks of ______ within the chloroplasts. a. thylakoids b. carotenoids c. prolamellar bodies d. stroma e. etioplasts
thylakoids