bio test 2
The complete oxidation of a mole of glucose releases 686 kcal of energy (∆G = -686 kcal/mol). ________ The phosphorylation of ADP to form ATP stores approximately 7.3 kcal per mole of ATP. What is the approximate efficiency of cellular respiration for a "mutant" organism that produces only 29 moles of ATP for every mole of glucose oxidized, rather than the usual 36-38 moles of ATP?
30%
Which of the following is TRUE for endergonic reactions? ________
A net input of energy is required for these reactions to proceed.
Certain drugs act as ionophores that cause the mitochondrial inner membrane to be highly permeable to H+. How would such drugs affect oxidative phosphorylation?
ATP synthesis would be inhibited
Patients with McArdle's Disease lack an enzyme in their livers that catabolizes glycogen. ________ Compared to an unaffected individual, what would you predict about the blood glucose levels of a patient with McArdle's disease?
Blood glucose levels would be lower because they cannot break down glycogen.
The ATP synthase enzyme is located
Both B and C
A bowl of sugar water is very stable. However, cells can rapidly break down sugar into carbon dioxide and water. What is the best explanation for this observation?
Enzymes in the cell catalyze the breakdown of glucose.
Which of the following represents a reactant or input for the light reaction of photosynthesis? _______
H2O
___________________ consume organic molecules to live.
Heterotrophs
In the biochemical regulation of metabolic pathways, how might one overcome the effects of a competitive inhibitor on enzyme activity?
Increase the amount of substrate for the enzyme.
Which of the following statements is CORRECT about active transport? __________
It is an active process in which molecules move from a region of lower concentration to one of higher concentration
Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?
The light reactions provide ATP and NADPH to the Calvin cycle.
When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs?
The pH of the matrix increases
Which of the following is TRUE for a reaction that has a ∆G > 0? ________
The products have more free energy than the reactants
Which of the following is TRUE for a reaction that has a negative change in free energy (- ∆G) _______
The reaction will yield energy and is spontaneous
Which of the following is FALSE when comparing the mitochondria and chloroplast?
The stroma of chloroplasts is similar to that of the mitochondrial inner-membrane space insofar as each has a higher H+ concentration relative to that of the chloroplast thylakoid lumen and the mitochondrial matrix.
A series of enzymes catalyze the reaction X > Y > Z > A. Product A binds to the enzyme that ________ converts X to Y at a position remote from its active site. This binding decreases the activity of the enzyme. Substance A functions as
a non-competitive inhibitor and an allosteric inhibitor.
Which of the following function: location relationships is INCORRECT? _______
acetyl CoA formation; cytosol
A comparison of mitochondria and chloroplasts shows that
both generate ATP via an H+ electrochemical gradient.
Which portion of the photosynthetic apparatus absorbs light?
both photosystem I and photosystem II
Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? _________
catabolism
Where does the Calvin cycle occur?
chloroplast stroma
After ATP donates a phosphate group in a coupled reaction, it becomes ADP. The ADP can be converted back to ATP in a(an) ________ reaction
endergonic
The free energy (G) of the reactants for a particular reaction is 100 kcal/mol and the _________ free energy (G) of the products is 50 kcal/mol. This reaction is
exergonic
Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism As _____________ is to ___________________.
exergonic; endergonic
A series of enzymes catalyze the reactions ABCD. Substance "D" binds to the enzyme that converts A to B and decreases the activity of the enzyme. What is going on here?
feedback inhibition
Which compound has the highest free energy and produces the most ATP when oxidized? _______
glucose
Which of the following processes will occur in the presence or absence of oxygen?
glycolysis
Which of the following produces NADPH
light reactions alone
The molecule that functions as the reducing agent in a redox or oxidation-reduction reaction. _________
loses electrons and loses energy.
Energy released by the electron transport chain is used to pump H+ ions into which location ________
mitochondrial intermembrane space
Cellular respiration produces the most ATP from which of the following?
oxidative phosphorylation
In the following chemical reaction, NADH loses electrons and is converted to NAD+ + H+ In this reaction NADH has been
oxidized
In cellular respiration, the final electron acceptor in the electron transport chain is
oxygen
Which of the following may alter the function of an enzyme?
pH, temperature, and mutations
To breakdown glucose to carbon dioxide and water, which of the following is not involved?
photosynthesis
The primary function of an enzyme or any biological catalyst is to
reduce the energy of activation and increase the rate of a reaction.
The ATP made during glycolysis is generated by
substrate-level phosphorylation.
Some bacteria are metabolically active in hot springs. Most likely, this is because
their enzymes have high optimal temperatures
