BIOLOGY 1201 EXAM 2 QUESTIONS & ANSWERS
Of the following functions, which is most important for the glycoproteins and glycolipids
of animal cell membranes?
A)facilitated diffusion of molecules down their concentration gradients
B)active transport of molecules against their concentration gradients
C)maintaining the integrity of fluid mosaic membrane
D)maintaining membrane at low temperatures
E)a cell's ability to distinguish one type of neighboring cell from another - Answers :E)a
cell's ability to distinguish one type of neighboring cell from another
Which of the following is an example of potential rather than kinetic energy?
A) H+ flowing through ATP Synthase
B) Electrons moving through an electron transport chain
C) A firefly using light flashes to attract a mate
D) Electrons in a protein
E) Electrons in CO2 - Answers :D)electrons in a protein
When glucose monomers are joined together by glycosidic linkages to forma cellulose
polymer, the changes in free energy, total energy, and entropy are as follows: - Answers
:+△G, +△H, -△S
What would happen if enzymes did not mediate catabolic, exergonic reactions of large
molecules in organisms? - Answers :All their energy would be lost as heat
During a laboratory experiment, you discover that an enzyme-catalyzed reation has a
△G of -20kcal/mol. If you double the amount of enzyme in the reaction, what will be the
△G for the new reaction? - Answers :-20 kcal/mol
Which of the following metabolic processes can occur without a net influx of energy
from some other processes?
A) ADP + Pi ---> ATP + H2O
B) C6H12O6 + 6 O2---> 6 CO2 + 6 H2O
C) 6 CO2 + 6 H2O---> C6H12O6 + 6 O2
D) amino acids---> protein
E) glucose + fructose--->sucrose - Answers :B)C6H12O6+6O2--->6CO2+6H2O
The mechanism in which the end product of a metabolic pathway inhibits an earlier step
in the pathway is known as what? - Answers :Feedback inhibition
What happens to the molecule that functions as the reducing agent (electron donor) in a
redox or oxidation-reduction reaction? - Answers :It loses electrons and loses energy
Which of the following statements describes NAH+?
, A) NAD+ is reduced to NADH during both glycolysis and the citric acid cycle.
B) NAD+ has more chemical energy than NADH.
C) NAD+ is reduced by the action of hydrogenases.
D) NAD+ can donate electrons for use in oxidative phosphorylation.
E) In the absence of NAD+, glycolysis can still function. - Answers :A)NAD+ is reduced
to NADH during both glycolysis and citric acid cycle
The ATP made during the Krebs Cycle is generated by what? - Answers :substrate-level
phosphorylation
What process in eukaryotic cells will proceed normally whether oxygen is present or
absent? - Answers :glycolysis
An electron loses potential energy when it...
A) shifts to a less electronegative atom.
B) shifts to a more electronegative atom.
C) increases its kinetic energy.
D) increases its activity as an oxidizing agent. - Answers :B) shifts to a more
electronegative atom
Why are carbohydrates and fats considered high energy foods? - Answers :They have a
lot of electrons associated with hydrogen
In addition to ATP, what are the end products of glycolysis? - Answers :NADH and
pyruvate
When is most CO2 from catabolism is released? - Answers :during the Kreb's cycle
a molecule that is phosphorylated... - Answers :has an increased chemical reactivity; it
is primed to do cellular work
In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in
the citric acid cycle. First, however, the pyruvate 1) loses a carbon, which is given off as
a molecule of CO2, 2) is oxydized to forma two-carbon compound called acetate, and 3)
is bonded to coenzyme A. What do these three steps result if the formation of? -
Answers :acetyle CoA, NADH, and CO2
How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of
one molecule of pyruvate? - Answers :2
During aerobic respiration, which of the following directly donates electrons to the
electron transport chain? - Answers :NADH
During oxidative phosphorylation, H2O is formed. Where does the oxygen for the
synthesis of the water come from? - Answers :molecular oxygen (O2)
Of the following functions, which is most important for the glycoproteins and glycolipids
of animal cell membranes?
A)facilitated diffusion of molecules down their concentration gradients
B)active transport of molecules against their concentration gradients
C)maintaining the integrity of fluid mosaic membrane
D)maintaining membrane at low temperatures
E)a cell's ability to distinguish one type of neighboring cell from another - Answers :E)a
cell's ability to distinguish one type of neighboring cell from another
Which of the following is an example of potential rather than kinetic energy?
A) H+ flowing through ATP Synthase
B) Electrons moving through an electron transport chain
C) A firefly using light flashes to attract a mate
D) Electrons in a protein
E) Electrons in CO2 - Answers :D)electrons in a protein
When glucose monomers are joined together by glycosidic linkages to forma cellulose
polymer, the changes in free energy, total energy, and entropy are as follows: - Answers
:+△G, +△H, -△S
What would happen if enzymes did not mediate catabolic, exergonic reactions of large
molecules in organisms? - Answers :All their energy would be lost as heat
During a laboratory experiment, you discover that an enzyme-catalyzed reation has a
△G of -20kcal/mol. If you double the amount of enzyme in the reaction, what will be the
△G for the new reaction? - Answers :-20 kcal/mol
Which of the following metabolic processes can occur without a net influx of energy
from some other processes?
A) ADP + Pi ---> ATP + H2O
B) C6H12O6 + 6 O2---> 6 CO2 + 6 H2O
C) 6 CO2 + 6 H2O---> C6H12O6 + 6 O2
D) amino acids---> protein
E) glucose + fructose--->sucrose - Answers :B)C6H12O6+6O2--->6CO2+6H2O
The mechanism in which the end product of a metabolic pathway inhibits an earlier step
in the pathway is known as what? - Answers :Feedback inhibition
What happens to the molecule that functions as the reducing agent (electron donor) in a
redox or oxidation-reduction reaction? - Answers :It loses electrons and loses energy
Which of the following statements describes NAH+?
, A) NAD+ is reduced to NADH during both glycolysis and the citric acid cycle.
B) NAD+ has more chemical energy than NADH.
C) NAD+ is reduced by the action of hydrogenases.
D) NAD+ can donate electrons for use in oxidative phosphorylation.
E) In the absence of NAD+, glycolysis can still function. - Answers :A)NAD+ is reduced
to NADH during both glycolysis and citric acid cycle
The ATP made during the Krebs Cycle is generated by what? - Answers :substrate-level
phosphorylation
What process in eukaryotic cells will proceed normally whether oxygen is present or
absent? - Answers :glycolysis
An electron loses potential energy when it...
A) shifts to a less electronegative atom.
B) shifts to a more electronegative atom.
C) increases its kinetic energy.
D) increases its activity as an oxidizing agent. - Answers :B) shifts to a more
electronegative atom
Why are carbohydrates and fats considered high energy foods? - Answers :They have a
lot of electrons associated with hydrogen
In addition to ATP, what are the end products of glycolysis? - Answers :NADH and
pyruvate
When is most CO2 from catabolism is released? - Answers :during the Kreb's cycle
a molecule that is phosphorylated... - Answers :has an increased chemical reactivity; it
is primed to do cellular work
In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in
the citric acid cycle. First, however, the pyruvate 1) loses a carbon, which is given off as
a molecule of CO2, 2) is oxydized to forma two-carbon compound called acetate, and 3)
is bonded to coenzyme A. What do these three steps result if the formation of? -
Answers :acetyle CoA, NADH, and CO2
How many carbon atoms are fed into the citric acid cycle as a result of the oxidation of
one molecule of pyruvate? - Answers :2
During aerobic respiration, which of the following directly donates electrons to the
electron transport chain? - Answers :NADH
During oxidative phosphorylation, H2O is formed. Where does the oxygen for the
synthesis of the water come from? - Answers :molecular oxygen (O2)
