Download Exam 2 Practice - Nicholls State University

Exam 2 Practice
October 5, 2015
Biology 155
1. From the Second Law of Thermodynamics you
know that
a. the universe has a constant amount of energy
b. all chemical reactions are reversible
c. the amount of kinetic energy in the universe is
always increasing
d. energy can be converted from one form to
another
2. In any chemical reaction, the total amount of
product that can be produced is determined by
a. the rate of reaction
b. the difference in potential energy between the
substrate and the product
c. the amount of energy that must be invested to
make the reaction proceed
d. the amount of potential energy in the product
3. For the reactions shown above, which statement is
NOT correct? Assume equal starting concentrations
of the substrates for both reactions.
a. both reactions are exergonic
b. both reactions will occur at the same rate
c. at equilibrium, both reactions will produce the
same amount of product
d. reaction 2 has a lower activation energy than
reaction 1
4. A competitive inhibitor can be recognized by which
property?
a. the inhibitor can be saturated
b. the amount of inhibition can be decreased by
increasing substrate concentration
c. the amount of inhibition can be decreased by
decreasing substrate concentration
d. the percentage inhibition changes with change
in enzyme concentration
Name__________________________
5. The currency of energy in cells is
a. NADH
b. ATP
c. carbohydrates
d. triglycerides
6. Which substance is a coenzyme?
a. NAD
b. catechol oxidase
c. Rubisco
d. calcium ion
7. Which statement about enzyme catalyzed reactions
is NOT correct?
a. enzymes decrease the activation energy of a
reaction
b. enzymes can change the amount of product
produced at equilibrium
c. a change in substrate concentration can change
the rate of a reaction
d. small changes in enzyme shape can influence
the rate of a reaction
8. In the conversion of a substrate into a product the
activation energy determines
a. the amount of energy that the reaction can yield
b. the amount of potential energy in the product
c. the rate of reaction
d. the total amount of product at equilibrium
9. A noncompetitive inhibitor can be recognized by
which property?
a. the percentage inhibition changes with change
in enzyme concentration
b. the inhibition is reversible by adding more
substrate
c. the degree of inhibition does not change with
change in substrate concentration
d. the inhibitor can be saturated
10. Which substance is most likely to be a cofactor?
a. NAD+
b. ATP
c. AMP
d. Ca++
11. In theory, how many ATP can be produced from
one molecule of glucose under ideal conditions by a
eukaryotic cell?
a. 25 b. 30 c. 32 d. 38
12. An allosteric regulator is a substance that
a. influences the amount of product in solution
b. changes the free energy of a reaction
c. influences an enzyme's properties by binding to it
away from the active site
d. influences an enzyme's properties by binding to it
at the active site
13. In theory, how many ATP can be produced from
one molecule of acetyl CoA under ideal conditions
by a eukaryotic cell?
a. 8
b. 10
c. 15
d. 12
14. Which statement about glycolysis and respiration is
NOT correct?
a. glycolysis can occur in either the cytoplasm or
mitochondrion
b. the Krebs cycle only occurs in the mitochondrion
c. proton gradients are responsible for most ATP
production in the mitochondrion
d. water is the final product of the electron transport
chain
15. Which is NOT a product of the Krebs cycle?
a. Acetyl CO-A b. NADH c. ATP d. CO2
16. Which statement about glycolysis is NOT correct?
a. it can occur in the absence of oxygen
b. glucose is completely degraded to CO2 and H20
c. 2 ATP must be invested to begin the process
d. the net ATP yield is 2
17. Which statement about formation of ATP in the
electron transport chain of the mitochondrion is
NOT correct?
a. protons are pumped out of the matrix
b. an proton concentration gradient drives ATP
formation
c. electron transport involves a series of oxidationreduction reactions
d. CO2 is the final acceptor of electrons
18. If glucose was completely degraded to CO2 and
H2O, how many of the total ATP produced are
produced by substrate level phosphorylation?
a. 2 b. 4 c. 8 d. 12
19. If you were to compare the pH of mitochondrial
matrix with the pH of the intermembrane space
during active respiration you would find
a. they would be the same
b. the pH of the matrix would be lower
c. the pH of the matrix would be higher
20. The Krebs cycle depends on the presence of many
molecules. Which molecule is NOT required by the
Krebs cycle?
a. NAD b. ADP c. H2O d. acetyl CoA
21. Which compound is NOT produced during
anaerobic glycolysis?
a. ATP
b. pyruvate
d. lactic acid
c. FADH2
22. When carbohydrates are taken into a cell they can
be used for energy production or they can be stored
for later use. What molecule can serve as a
regulator of this process?
a. glucose
b. pyruvate
c. lactic acid
d. ATP
23. The actual yield of ATP from each molecule of
glucose is about 20% less than the theoretical yield
under ideal conditions. Which explanation is
currently considered the best explanation for this
difference?
a. because the Second Law of Thermodynamics
does not allow it
b. because some protons leak through the inner
mitochondrial membrane
c. because NADH produced in glycolysis cannot
be used to produce ATP
d. because cells seldom receive enough oxygen to
be 100% efficient
24. Which statement about B-oxidation is correct?
a. deamination is required before it begins
b. it ultimately yields fewer ATP molecules per
carbon than does glucose
c. it can’t be carried out anaerobically
d. most of the process occurs in the cytoplasm
25. Which reaction is exergonic?
a. ADP → ATP
b. NADP → NADPH
c. glucose → pyruvate
d. 6CO2 + 12H2O → C6H12O6 + 6 H20 + 6O2
26. If you could completely isolate the light reactions of
photosynthesis from the dark reactions, which of the
following would you not expect to find associated
with the light reactions?
a. ATP b. O2 c. CO2 d. NADPH
27. If you could completely isolate the light reactions of
photosynthesis from the dark reactions, which of the
following would you not expect to find associated
with the dark reactions?
a. CO2
b. NADPH c. ATP d. O2
28. Which statement about the light reactions of
photosynthesis is NOT correct?
a. proton gradients are responsible for most ATP
production
b. electrons are excited when chlorophyll absorbs
photons
c. electrons are excited first in Photosystem II
d. the excited electrons originally came from O2
29. If you homogenized spinach cells, isolated the
chloroplasts from the other parts of the cells, and
then shined light on the chloroplasts you would
expect
a. CO2 to be produced
b. O2 to be produced
c. NADH to be produced
d. pyruvate to be converted to lactic acid
30. Which statement about light absorption by green
plants is correct?
a. green light is best for the production of oxygen
b. light is most strongly absorbed in the red and
blue regions of the spectrum
c. chlorophyll a only absorbs red light and
chlorophyll b only absorbs blue light
d. most photosynthesis is powered by light that is
not visible to humans
31. During photosynthesis plants absorb CO2 from the
atmosphere. If you could follow the oxygen atoms
associated with CO2 through all the reactions of
photosynthesis, at the end of the process you would
find those atoms
a. as free oxygen (O2)
b. as free oxygen and as part of water
c. still only associated with CO2 gas
d. as part of water and carbohydrates
32. If you could measure the pH of the space inside the
thylakoid membranes and the pH in the stroma of
chloroplasts during the light reactions of
photosynthesis, what would you find?
a. the pH would be higher in the stroma
b. the pH would be lower in the stroma
c. the pH of both spaces would be the same
33. Which statement about the Calvin cycle is NOT
correct?
a. one product is glyceraldehyde 3-phosphate
b. NADPH is used to reduce organic compounds
c. RUBISCO plays an important role in carbon
fixation
d. it can only occur in the dark
34. Which statement about the light reactions is NOT
correct?
a. protons are pumped as electrons are passed
through an electron transport chain
b. protons are pumped from the inside to outside of
thylakoids
c. NADP is the final acceptor of electrons
d. the original source of electrons is water
35. Which statement about the cell cycle is NOT
correct?
a. DNA is replicated during prophase
b. most cells spend most of their time in interphase
c. cytokinesis usually follows telophase
d. G1, S, and G2 are collectively referred to as
interphase
36. Before cell division each chromosome replicates
and afterwards consists of two parts. The parts are
connected by a centromere and are called:
a. sister chromatids
b. daughter chromatids
c. sister chromosomes
d. spindle fibers
37. Which statement about mitosis is NOT correct
a. chromatids separate during anaphase
b. chromosomes pair during prophase
c. spindle fibers form during prophase
d. the daughter cells are genetically identical to the
parent cell
38. Red blood cells are continually wearing out and are
replaced by the division of cells in bone marrow. If
you were to look at actively dividing cells in live
bone marrow under a microscope you would NOT
find cells in what stage?
a. interphase
b. G1
c. telophase
d. G0
39. The diagram above shows a cell that is probably in
a. prophase
b. telophase
c. metaphase
d. anaphase
e. interphase
40. Cancer is
a. uncontrolled cell growth
b. a genetic disease
c. caused by mutations
d. all of the above
41. Why does the incidence of cancer increase with
age?
a. repair systems wear out
b. the immune system weakens
c. it requires time to accumulate mutations
d. older people are exposed to more risk factors
42. Which statement about growth factors is NOT
correct?
a. growth factors can be produced by the same
tissue they stimulate to grow
b. growth factors are only produced early in life
c. the presence of certain growth factors may
determine if a cell leaves the G1 stage
d. growth factors can stimulate either a broad
range of tissues or a narrow range of tissues to
begin growth
For up to 10 points:
Compare the end products and total energy yield for the
following two processes: 1) Glycolysis and respiration,
2) fermentation in muscle cells. What problem does
fermentation solve? What problem does fermentation
create? What is oxygen debt?
Key
1
c
11
b
21
c
31
d
41
c
2
b
12
c
22
d
32
a
42
b
3
b
13
b
23
b
33
d
43
4
b
14
a
24
c
34
b
44
5
b
15
a
25
c
35
a
45
6
a
16
b
26
c
36
a
46
7
b
17
d
27
d
37
b
47
8
c
18
b
28
d
38
d
48
9
c
19
c
29
b
39
c
49
10
d
20
c
30
b
40
d
50