Bio Lec Exam 3 Flashcards
1
TRUE
This is a true statement: The first event in
the Calvin cycle is the attachment of carbon
dioxide to the five-carbon RuBP molecule,
which forms a six-carbon molecule that
immediately breaks down into two 3PG
molecules.
2
2) TRUE
This is a true statement: The first event in
the Calvin cycle is the attachment of carbon
dioxide to the five-carbon RuBP molecule,
which is a reaction assisted by large
quantities of RuBP carboxylase enzyme.
3
3) TRUE
This is a true statement. The first event in
the Calvin cycle is the attachment of carbon
dioxide to the five-carbon RuBP molecule,
which decreases cell carbon dioxide levels,
which increases the diffusion gradient.
4
4) FALSE
This is a false statement. The first event in
the Calvin cycle is the attachment of carbon
dioxide to the five-carbon RuBP molecule,
but this six-carbon sugar is not immediately
used to produce starch, sucrose, cellulose,
etc.
5
5) TRUE
It is true that fossil fuels are full of energy
stored from photosynthesis millions of years
ago.
6
6) FALSE
It is not true that the light-dependent
reactions of photosynthesis occur in the
stroma of the chloroplast. These reactions
occur in the thylakoid membranes.
7
7) FALSE
Chemiosmotic ATP synthesis more
specifically occurs in chloroplasts.
8
8) FALSE
Photorespiration is a process that occurs in
the presence of light when there is high
oxygen and low carbon dioxide
concentrations in leaves. Oxygen is taken
up, combines with RuBP, and produces one
molecule of 3PG and carbon dioxide.
9
9) TRUE
It is true that plants in hot, dry climates
conduct metabolism and are desert plants.
10
10) TRUE
It is true that phosphoenolpyruvate
carboxylase fixes carbon dioxide to PEP to
form oxaloacetate within mesophyll cells of
the plants.
11
11) FALSE
This is not a true statement. Oxygen is the
final electron acceptor in the electron
transport chain which is located in the
cristae of the mitochondria. Glycolysis is an
anaerobic process that occurs in the cytosol
of the cell.
12
12) TRUE
It is true that fermentation follows glycolysis
in some cells when oxygen is not available.
13
13) FALSE
Each molecule of NADH produced in the
mitochondria provides the energy for three
ATP molecules.
14
14) TRUE
It is true that the breakdown of glucose in
cellular respiration is a catabolic reaction.
15
15) TRUE
It is true that fermentation is the process that
produces bubbles of carbon dioxide that
makes bread dough rise.
16
16) TRUE
It is true that chloroplasts perform
photosynthesis and photosynthesis is the
most common anabolic process on the
planet.
17
17) TRUE
It is true that viruses and chemical exposure
can cause mutations in proto-oncogenes
which can lead to cancer.
18
18) TRUE
It is true that the enzymes that bring about
apoptosis are called caspases.
19
19) TRUE
It is true that the enzymes that bring about
apoptosis are ordinarily held in check by
inhibitors.
20
20) TRUE
It is true that the enzymes that bring about
apoptosis can be unleashed by internal or
external signals.
21
21) FALSE
The enzymes that bring about apoptosis are
always present in the cell, but are controlled
by internal and external signals.
22
22) FALSE
It is not true that cloning can only be carried
out using adult stem cells. Embryonic stem
cells can be used as well.
23
23) TRUE
It is true that normal cells exhibit contact
inhibition, but cancer cells do not.
24
24) TRUE
It is true that, generally, brain and nerve
cells are not able to regenerate after injury
because they have left the cell cycle and are
unable to return.
25
25) FALSE
It is not true that organisms produced as a
result of mitosis exhibit a great deal of
genetic variation.
26
26) [A, C, D]
Chlorophyll a, chlorophyll b, and the
carotenoids are all common photosynthetic
pigments used by plants. Chlorophyll c is a
common pigment found in aquatic marine
algae.
27
27) [A, B, D]
G3P, the end product of the Calvin cycle,
can be used by the plant to make glucose,
sucrose, starch, cellulose, glycerol, and fatty
acids as well as amino acids. Carbon dioxide
and NADPH are not made from G3P.
28
28) [A, B, C, E]
plants store carbon dioxide temporarily as
oxaloacetate because plants separate
carbon fixation from the Calvin cycle. By
doing this, plants experience lower levels
of photorespiration as compared to plants.
plants are adapted to hot, dry climates.
29
29) [A, B]
Plants rely on the light reactions to split
water (which releases ), and generate ATP
and NADPH. Without the light reactions,
would not be released and ATP and NADPH
production would cease. Ultimately, the
Calvin cycle would produce G3P in much
smaller quantities.
30
30) [B, C, D]
During photosynthesis, water is split,
releasing oxygen as a waste product, at the
beginning of photosystem II (which
precedes photosystem I). The photosystems
are part of the light reactions.
31
31) [A, B, D]
If the stomata remained closed all day, gases
would not be exchanged. Therefore carbon
dioxide levels within the leaf would
decrease and oxygen levels would increase.
As a result, photorespiration would increase
in plants. CAM plants would be unaffected
because they have adapted to living in hot,
dry climates and they normally keep their
stomata closed during the day. Since water
enters a plant through the roots rather than
the stomata, closing the stomata would not
result in a decrease in the amount of water
within the leaf.
32
32) [A, C, E]
Photorespiration is a process that occurs in
the presence of light when there is high
oxygen and low carbon dioxide
concentrations in leaves. Oxygen is taken
up, combines with RuBP, and produces one
molecule of 3PG and eventually produces
carbon dioxide.
33
33) B
Oxygen is the final electron acceptor of the
electron transport chain.
34
34) [B, E, F]
Fermentation permits cells to produce ATP
under anaerobic conditions. The process of
fermentation follows glycolysis. It reduces
pyruvate to either lactate (in animals) or
alcohol (in plants and yeast) and oxidizes
NADH to . The is then used for
glycolysis.
35
35) [A, B, C]
It is true that animal cells have centrioles but
plant cells do not. Both plant and animal
cells grow via mitosis and both undergo
cytokinesis, but animals cell pinch into two
daughter cells while plant cells divide by the
formation of a new cell plate.
36
36) [A, D, E]
Mitosis is the process that divides the
contents of the nucleus (the chromosomes)
during the cell cycle. Mitosis starts with a
diploid parent cell and ends with two diploid
daughter cells. These daughter cells are
genetically identical (in chromosome
number and genes) to the original parent cell
but may differ in size and number of
organelles. Mitosis is also the process that
allows for growth in a multicellular
organism.
37
37) [A, C]
Both benign and malignant tumors are forms
of abnormal cell growth. Malignant tumors
can grow large and metastasize while benign
tumors tend to be small and stay in one
place. A benign tumor can become a
malignant tumor if it accumulates enough
mutations and it can no longer control the
cell cycle.
38
38) [A, B, C]
DNA compaction begins when DNA is
wound around histone proteins giving it the
appearance of a string of beads. DNA is then
folded into a zigzag pattern before being
formed into radial loops. The DNA is not
cut into smaller pieces.
39
39) [A, B, D]
In areas where genes need to be transcribed,
the chromatin would be loosely coiled
(euchromatin). Heterochromatin is more
tightly coiled and contains DNA that is not
being transcribed. During mitosis, the DNA
must be tightly compacted in order to move
it around the cell. Most chromosomes have
some areas that are loosely compacted and
some areas that are tightly compacted.
40
40) [C, D]
The enzymes that bring about apoptosis,
called caspases, are always present in the
cell. The enzymes are ordinarily held in
check by inhibitors, but they can be
unleashed by either internal or external
signals.<!--Markup Copied from Habitat-->
41
41) [B, C, E]
Both embryonic and adult stem cells can be
used in therapeutic cloning which is the
production of tissues that may be used to
cure illnesses. Only embryonic stem cells
can be used for reproductive cloning which
is the production of a new individual
organism.
42
42) [C, D]
Contact inhibition cases normal cells to stop
dividing when they come into contact with
neighboring cells. It is not functioning in
cancer cells which allows them to continue
growing on top of one another and form a
tumor.
43
43) [A, D]
Nerve cells and muscle cells are typically in
a stage called G0 in which they have left
interphase and are not preparing to divide.
For this reason these tissue types usually do
not regenerate after injury.
44
44) D
Plants are green because they absorb all of
the colors in the visible light spectrum
except the green wavelengths. The green
wavelengths are reflected off the plant and
are available for our eyes to see.
45
45) C
The products of photosynthesis are
carbohydrate and oxygen. The oxygen is
produced as a waste product during the light
reactions, while the carbohydrate is the end
product of the Calvin cycle.
46
46) D
Plants, algae, and some bacteria are capable
of photosynthesis.
47
47) A
Photorespiration occurs mainly in plants.
48
48) C
RuBP carboxylase catalyzes the reaction
that fixes carbon dioxide to RUBP at the
beginning of the Calvin cycle.
49
49) D
Stroma is the central fluid-filled space of the
chloroplast. This word can easily be
confused with the term “stoma,” a pore on
the underside of a leaf that facilitates the
exchange of carbon dioxide and oxygen.
50
50) C
Grana refers to a stack of thylakoid
membranes.
51
51) E
The hydrogen protons in the thylakoid space
move from the thylakoid space to the stroma
through an ATP synthase complex that
generates ATP.
52
52) A
The chloroplast is the structure that makes
an organism an autotroph.
53
53) E
The noncyclic electron pathway does not
produce carbohydrates through carbon
dioxide fixation. This happens in the Calvin
Benson cycle.
54
54) C
Carbon dioxide fixation is most closely
associated with the Calvin cycle.
55
55) C
Glyceraldehyde-3-phosphate (G3P) is a
product of the Calvin cycle that is used to
form glucose phosphate, amino acids or
fatty acids.
56
56) A
The major enzyme that “fixes” carbon
dioxide is RuBP carboxylase (rubisco). PEP
carboxylase is an enzyme used in
photosynthesis to help minimize the effects
of photorespiration. G3P is the end product
of the Calvin cycle, not an enzyme. Lactate
dehydrogenase is an enzyme involved in
cellular respiration rather than
photosynthesis.
57
57) C
The function of sunlight in photosynthesis is
to excite electrons within the chlorophyll a
molecule located in the reaction center of a
photosystem.
58
58) A
59
59) C
A product of photosynthesis, glucose, is the
chief source of energy for most organisms.
60
60) B
61
61) A
While C4 plants have carbon dioxide
fixation and carbon dioxide uptake separated
by location within the plant, CAM plants
have these processes separated by time.
62
62) A
If narrow bands of unicolored light were
shown on an aquatic plant such as Elodea,
the number of bubbles of oxygen produced
could be counted as an indicator of
photosynthetic rate. A graph of
photosynthetic activity would appear just
like the action spectrum with peaks at
violet/blue and orange/red and a trough at
yellow/green.
63
63) C
When the chlorophyll is packaged inside
chloroplasts and the red or blue light is
turned on, there is no fluorescence because
the excited electrons are transferred to
electron acceptors in the chloroplast.
64
64) D
65
65) A
66
66) A
The energized electrons are taken up by
NADP+ to produce NADPH.
67
67) A
During the Calvin cycle, the is absorbed
and reduced
68
68) B
The first event in the Calvin cycle is the
attachment of carbon dioxide to the five-
carbon RuBP molecule, which forms a six-
carbon molecule that immediately breaks
down into two 3PG molecules.1
69
69) B
The reaction to add carbon dioxide to RuBP
is unusually slow. It processes only a few
molecules of substrate per second compared
to thousands per second for a typical
enzyme.<!--Markup Copied from Habitat-->
70
70) C
After carbon dioxide binds to RuBP it
immediately breaks down into two
molecules of 3PG.
