Energetics quiz
A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible lights are *not* being absorbed by this pigment?
red and yellow
Where do the enzymatic reactions of the Calvic cycle take place?
storm of the chloroplast
Where does the Calvin cycle take place?
storm of the chloroplast
What is the primary function of the Calvin cycle?
synthesize simple sugars from carbon dioxide
the direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation is
the difference in H+ concentrations on opposite sides of the inner mitochondrial membrane
Which of the following reactions is most likely to be coupled to the reaction ATP+H2O→ADP+Pi ( ∆G=-7.3 kcal/mol)?
E+Pi→EP(∆G=+5 kcal/mol)
What are the products of the light reactions that are subsequently used by the Calvin cycle?
ATP and NADPH
When glucose (C6H12O6) is oxidized to CO2 and water in cellular respiration, approximately 40% of the energy content of glucose is transferred to
ATP
Which of the following products of the light reactions of photosynthesis that are utilized in the Calvin Cycle?
ATP and NADPH
In which cell would you expect photorespiration?
Cell II
What do both mitochondria and chloroplast have in common?
-chemiosmosis -ATP synthase
During photosynthesis visible light has enough energy to
-excite electrons -split a water molecule into hydrogen and oxygen
which of the following statements about glycolysis is true?
-glycolysis has steps involving oxidation-reduction reactions -the enzymes of glycolysis are located in the cytosol of the cell -glycolysis can operate in the complete absence of O2 -glycolysis makes ATP exclusively through substrate-level phosphorylation
Which of the following statements is true concerning the figure?
-it represents cell processes involved in C4 photosynthesis -it represents an adaptation that minimizes photorespiration
How many molecules of CO2would be produced by five turns of the citric acid cycle?
10
how many carbon atoms are fed into the citric acid cycle as a result of one molecule of pyruvate?
2
in glycolysis, for each molecule of glucose oxidized to pyruvate
2 molecules of ATP are used and 4 molecules of ATP are produced
Starting with citrate, how many of the following would be produced with three turns of the citric acid cycle?
3 ATP, 6 CO2, 3 NADH, and 3 FADH2
What wavelength of light is most effective in driving photosynthesis?
420 mm
What does cyclic electron flow in the chloroplast produce?
ATP
in the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of
ATP, CO2, and ethanol
Plants that fix CO2 in organic acids at night when the stomata are open and carry out the Calvin cycle during the day when the stomata are closed are called
CAM plants
which type of organisms obtains energy by metabolizing molecules produced by other organisms? A. autotrophs B. heterotrophs C. decomposers D. B and C E. A, B, and C
D.
Which of the following statements regarding ATP is/are correct? A. ATP serves as a main energy shuttle inside cells B. ATP drives endergonic reactions in the cell by the enzymatic transfer of the phosphate group to specific reactants C. The regeneration of ATP from ADP and phosphate is an endergonic reaction D. A and B only E. A,B, and C
E.
in addition to ATP, what are the end products of glycolysis?
NADH and pyruvate
Which of the following is out similar in the structure of ATP
RNA nucleotides
The primary role of oxygen in cellular respiration is to
act as an acceptor for electrons and hydrogen, forming water
Organisms that can exist with light as an energy resource and an inorganic form of carbon and other raw materials
are called photoautotrophs
Which of the following produces the most ATP when glucose (C6H12O6) is completely oxidized to CO2 and water?
oxidative phosphorylation (chemiosmosis)
When 10,000 molecules of ATPare hydrolyzed to ADP and Pi in a test tube, about twice as much heat is liberated as when a cell hydrolyzes the same amount of ATP. Which of the following is the best explanation for this observation?
cells convert some energy of ATP hydrolysis into other forms of energy besides heat (transport, mechanical and chemical)
inside an active mitochondrion, most follow which pathway?
citric acid cycle→NADH→electron transport chain→oxygen *oxygen accepts electrons, so oxygen will be at the end and there is no app in the mitochondrion*
ATP generally energizes a cellular process by
coupling free energy released by ATP hydrolysis to free energy needed by other reactions
What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways?
energy coupling
CAM plants keep stomata closed in daytime, thus reducing loss of water. They can do this because they
fix CO2 into organic adds during the night
During aerobic respiration, electrons travel downhill in which sequence?
food→NADH→electron transport chain→oxygen
Which of the following normally occurs whether or not oxygen (O2) is present?
glycolysis
which of the following occurs in the cytosol of the cell?
glycolysis and fermentation
Phosphfructokinase is an allosteric enzyme that catalyzes the conversion of fructose-6-phosphate to fructose-, 6-biphosphate, an early step of glycolysis. In the presence of oxygen, an increase in the amount ATP in a cell would be expected to
inhibit the enzyme and thus slow the rates of glycolysis and the citric acid cycle
Why is ATP an important molecule in metabolism?
it provides energy coupling between exergonic and endergonic reactions
In C4 photosynthesis, carbon fixation takes place in the _______ cels, and then is transferred as magic or aspartic acid to ______ cells, where CO2 is release for entry into the Calvin cycle.
mesophyll; bundle-sheath
During cellular respiration, acetyl CoA accumulates in which location?
mitochondria matrix
where are the proteins of the electron transport chain located?
mitochondrial inner membrane
The figure below shows the absorption spectrum for chlorophyl a and the action spectrum for photosynthesis. Why are they different?
other pigments absorb light in additional to chlorophyll
Which metabolic process is most closely associated with intracellular membranes?
oxidative phosphorylation
Theodor W. Engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. He added aerobic bacteria and then noted in which areas the bacteria congregated. He noted that the largest groups were found in the areas illuminated by the red and blue light. An outcome of this experiment was to help determine
the relationship between wavelengths of light and the oxygen released during photosynthesis
Which of the following is true concerning catabolic pathways?
they are usually couple with anabolic pathways to which they supply energy in the form of ATP
Why are C4 plants able to photosynthesize with no apparent photorespiration?
they use PEP carboxylase to initially fix CO2
Where is the electron transport chain found in plant cells?
thylakoid membranes of chloroplasts
What is the primary function of the light reactions of photosynthesis?
to produce ATP and NADPH
