WorksheetsBiol 2170 Exam 2
Total questions: 189
Worksheet time: 3hrs 8mins
Name
Class
Date
1.
Animals such as cats, worms, and butterflies are classified as:
a)
photoheterotrophs
b)
chemoautotrophs
c)
chemoheterotrophs
d)
photoautotrophs
2.
Which one of the following is an example of potential energy?
a)
heat
b)
a moving muscle
c)
an electrochemical gradient
d)
light
3.
Which of the following statements is NOT one of the laws of thermodynamics?
a)
The energy available to do work decreases as energy is transformed from one form to the other
b)
None of the other answers are correct
c)
All cells arise from pre-existing cells
d)
The amount of energy in the universe is constant
4.
ATP is a good energy currency for cells because it has a(n) ____ amount of Gibbs free energy.
a)
Intermediate
b)
very high
c)
very low
5.
What is the function of an enzyme?
a)
To decrease amount of energy used to reach the transition state
b)
To both increase the rate of a specific reaction and decrease the amount of energy needed to reach the transition state
c)
To increase the rate of a specific reaction
d)
To alter the equilibrium of a specific reaction
6.
Reactions in which there is a negative change in free energy (-ΔG) are:
a)
Spontaneous and endergonic
b)
Nonspontaneous and exergonic
c)
Spontaneous and exergonic
d)
Nonspontaneous and endergonic
7.
Which of the following describes catabolic reactions?
a)
They are exergonic and have positive change in free energy.
b)
They are endergonic and have a negative change in free energy.
c)
They are exergonic and have a negative change in free energy.
d)
They are endergonic and have a positive change in free energy.
8.
ATP is chemically related MOST closely to which of the following?
a)
Phospholipid
b)
Guanine
c)
Tryptophan
d)
Glucose
9.
Suppose that three critical amino acids in the active site of a specific enzyme are arginine, lysine, and histidine. Which of the following characteristics would you predict the substrate to possess in order to bind to the active site of this enzyme?
a)
hydrophilic, with a positive charge
b)
hydrophilic, but without a charge
c)
relatively hydrophobic
d)
hydrophilic, with a negative charge
10.
Imagine that you discover a microbial deep-sea organism that can derive energy from (inorganic) hydrogen gas (H2). However, this microbe can also synthesize organic compounds from carbon-containing inorganic molecules in the ocean. This microbe is a:
a)
Photoheterotroph
b)
Chemoheterotroph
c)
Photoautotroph
d)
Chemoautotroph
11.
A molecule that is ____ loses electrons, and a molecule that is ____ gains electrons.
a)
negative; positive
b)
reduced; oxidized
c)
weak; polar
d)
oxidized; reduced
12.
Pyruvate oxidation is an important stage in cellular respiration because:
a)
It links glycolysis with the citric acid cycle
b)
It is the first step in oxidative phosphorylation
c)
It transfers large numbers of electrons to electron carriers
d)
It generates ATP by substrate-level phosphorylation
13.
The majority of the energy generated in the citric acid cycle is in the form of:
a)
ATP produced by substrate-level phosphorylation
b)
Electrons donated to NAD+ and FAD+
c)
GTP produced by oxidative phosphorylation
d)
ATP produced by oxidative phosphorylation
14.
In glycolysis, ATP is synthesized by:
a)
Electron carriers
b)
Substrate-level phosphorylation
c)
Both substrate level and oxidative phosphorylation
d)
oxidative phosphorylation
15.
Fermentation takes place:
a)
In the mitochondrial matrix
b)
In the inter membrane space of the mitochondria
c)
In cytoplasm
d)
On the inner mitochondrial membrane
16.
In the first three stages of cellular respiration, the chemical energy in glucose is transferred to:
a)
Cytochrome b and coenzyme Q
b)
Electron carriers and ATP
c)
ATP and cytochrome b
d)
Proton pumps and ATP
17.
In eukaryotes, pyruvate oxidation takes place in the:
a)
Cytoplasm
b)
Mitochondrial matrix
c)
Inner mitochondrial membrane
d)
Intermembrane space of mitochondria
18.
The citric acid cycle takes place in the:
a)
Outer mitochondrial membrane
b)
Cytoplasm
c)
Mitochondrial matrix
d)
Inter membrane space of mitochondria
19.
The final electron acceptor of the electron transport chain is:
a)
ATP synthase
b)
Oxygen
c)
NAD+
d)
Coenzyme Q
20.
Which best describes energy production during cellular respiration?
a)
A small amount of energy is produced by substrate-level phosphorylation; most is produced by oxidative phosphorylation
b)
A small amount of energy is produced by oxidative phosphorylation; most is produced by substrate-level phosphorylation
c)
An equal amount is produced by oxidative phosphorylation and substrate-level phosphorylation
d)
It depends on the organism. Some produce most of their energy by substrate-level phosphorylation, and some produce most of their energy by oxidative phosphorylation
21.
The proteins of the electron transport chain are:
a)
Embedded in the outer mitochondrial membrane
b)
Located in the mitochondrial matrix
c)
Embedded in the inner mitochondrial membrane
d)
Located in the intermembrane space of mitochondria
22.
Fermentation occurs in:
a)
Only bacteria and plants
b)
Some aerobic organisms, such as yeast, even in the presence of oxygen
c)
Anaerobic organisms only
23.
The breakdown of fatty acids takes place by a process called:
a)
Oxidative phosphorylation
b)
Glycolysis
c)
Beta-oxidation
d)
Pyruvate oxidation
24.
Cellular respiration is a series of ____ reactions.
a)
Anabolic
b)
Catabolic
c)
Phosphorylation
d)
Carboxylation
25.
Which of the following is not one of the net final products of glycolysis?
a)
Two molecules of ATP
b)
Two molecules of pyruvate
c)
Two molecules of acetyl-CoA
d)
Two molecules of NADH
26.
ATP is not generated directly in the citric acid cycle; instead, an intermediate is first generated by substrate-level phosphorylation. The intermediate is:
a)
Oxaloacetate
b)
GDP
c)
Acetyl-CoA
d)
GTP
27.
We consume a variety of carbohydrates that are digested into a variety of different sugars. How do these different sugars enter glycolysis?
a)
All sugars are converted to fructose 6-phosphate and enter glycolysis at phase 1, step 3
b)
All sugars are converted to glyceraldehyde 3-phosphate and enter glycolysis at phase 3, step 6
c)
All sugars are converted to glucose 6-phosphate and enter glycolysis at phase 1, step 2
d)
Sugars are converted to various forms and enter glycolysis at various stages
28.
Glycolysis is:
a)
Aerobic
b)
Anaerobic
c)
Aerobic in some organisms but anaerobic in others
d)
Aerobic in some tissues but anaerobic in others
29.
Which of the following statements is true regarding pyruvate oxidation?
a)
This process constitutes the second stage of cellular respiration and occurs within the matrix of mitochondria
b)
The process produces both CO2 and acetyl-CoA
c)
This process yields no ATP via substrate-level phosphorylation
d)
All choices are correct
30.
When a single pyruvate is converted to acetyl-CoA, the other products of the reaction are:
a)
FADH2 and ATP
b)
ATP and NADH
c)
NADH and CO2
d)
CO2 and ATP
31.
By the time pyruvate is formed, most of the energy contained in glucose has been released.
a)
True
b)
False
32.
Which of the following statements is true regarding aerobic respiration?
a)
Aerobic respiration requires oxygen at every stage of the process
b)
Aerobic respiration is a three-stage process, with oxidative phosphorylation comprising the last stage
c)
Carbon dioxide is produced at every stage of aerobic respiration
d)
None of the answers are correct
33.
Which stage of cellular respiration occurs immediately after pyruvate is produced?
a)
Glycolysis
b)
Pyruvate oxidation
c)
Citric acid cycle
d)
Electron transport
34.
Another name for acetyl-CoA synthesis, is:
a)
Pyruvate oxidation
b)
Pyruvate reduction
c)
Substrate-level phosphorylation
d)
Oxidative phosphorylation
35.
Like glycolysis, pyruvate oxidation produces both pyruvate and acetyl-CoA. These two products feed directly into the citric acid and are the reactants for the cycle.
a)
True
b)
False
36.
When glucose is broken down in a cell, all of the energy it stores is released simultaneously, not in a stepwise process.
a)
True
b)
False
37.
The first phase of glycolysis requires the input of two ATP molecules. It is therefore:
a)
Exergonic
b)
Oxidative
c)
Reducing
d)
Endergonic
38.
The ___ forms of the electron carriers NAD+/NADH and FADH/FADH2 have high potential energy.
a)
Oxidized
b)
Reduced
c)
Phosphorylated
d)
Carboxylated
39.
Which of the following statements is true regarding a reducing agent?
a)
It is never oxidized
b)
It loses electrons
c)
It gains electrons
d)
It is an electron acceptor
40.
In cellular respiration, oxygen:
a)
Gains electrons and is an oxidizing agent
b)
Loses electrons and is a reducing agent
c)
Gains electrons and is a reducing agent
d)
Loses electrons and is an oxidizing agent
41.
How did the earliest organisms on Earth most likely produce ATP?
a)
By glycolysis
b)
By pyruvate oxidation
c)
By oxidative phosphorylation
d)
By the citric acid cycle
42.
In the second phase of glycolysis:
a)
ATP is generated by substrate-level phosphorylation
b)
Phosphorylated sugar molecule is cleaved and the products rearranged
c)
NAD+ is reduced to NADH
d)
ATP is generated by oxidative phosphorylation
43.
The inputs to glycolysis do not include:
a)
Pi
b)
NAD+
c)
NADH
d)
ADP
44.
Which of the following statements is true regarding pyruvate and glucose?
a)
Glucose easily passes in and out of mitochondria, and can often be found in the mitochondrial matrix
b)
Glucose and pyruvate are remarkably similar in structure, with both molecules possessing a ring shape
c)
Both glucose and pyruvate can feed directly into the citric acid cycle, although acetyl-CoA is the preferred reactant for this process
d)
None are correct
45.
Pyruvate oxidation is remarkably similar to glycosides in that when one molecule of pyruvate enters into a mitochondrion, two molecules of acetyl-CoA are formed.
a)
True
b)
False
46.
After pyruvate oxidation, the chemical energy of how many carbons of the original glucose molecule is converted to chemical energy in the form of ATP in the remaining steps of cellular respiration?
a)
5
b)
4
c)
3
d)
2
47.
Although glycolysis produces four molecules of ATP by substrate-level phosphorylation, the net gain of ATP for the cell is two molecules. This is due to the fact that glycolysis is- at first- endergonic
a)
True
b)
False
48.
At the end of glycolysis, the carbon molecules originally found in the starting glucose molecule are in the form of:
a)
Two pyruvate molecules
b)
Four ATP molecules
c)
Two ATP molecules
d)
One pyruvate molecule
49.
During the action of ATP synthase, the kinetic energy of the proton gradient is transformed into potential energy.
a)
True
b)
False
50.
Fermentation produces nearly two times as much ATP as aerobic respiration, which explains why it is a preferred pathway for bacteria.
a)
True
b)
False
51.
The majority of cells within the human body have a very high baseline amount of ATP, so cells are always prepared for any long term activity.
a)
True
b)
False
52.
The ATP produced during glycolysis is the result of substrate-level phosphorylation.
a)
True
b)
False
53.
Pyruvate oxidation produces a large amount of ATP.
a)
True
b)
False
54.
Malate is both the starting and ending product of the citric acid cycle.
a)
True
b)
False
55.
Energy released by transferring electrons along the electron transport chain is stored as potential energy in the form of:
a)
Coenzyme Q
b)
ATP
c)
ATP synthase
d)
A proton gradient
56.
Starting with glycolysis, lactic acid and ethanol fermentation general only two ATP molecules per glucose molecule. The remaining chemical energy from the glucose is found primarily in:
a)
CO2
b)
GTP
c)
NADH
d)
Lactic acid and ethanol
57.
Oxidation is the gain of electrons.
a)
True
b)
False
58.
During the citric acid cycle:
a)
ATP is synthesized by oxidative phosphorylation
b)
High-energy electrons are removed from NAD+ and FADH
c)
Fuel molecules are completely reduced
d)
ATP is synthesized by substrate-level phosphorylation
59.
Coenzyme Q and cytochrome c:
a)
Transfer electrons between protein complexes of electron transport
b)
Transfer high-energy electrons from NADH and FADH2 to protein complexes of the electron transport chain
c)
Transfer electrons to ATP synthase
d)
Transfer electrons to oxygen at the end of the electron transport chain
60.
The majority of organisms on Earth can carry out some form of glycolysis.
a)
True
b)
False
61.
You may be familiar with Philippides, a famous Greek runner who ran the first marathon and then died after completing his run. Based on what you know of aerobic respiration and fermentation, why might he have died?
a)
His muscles may have produced toxic levels of lactic acid, causing his blood to become more acidic
b)
His muscles may have produced toxic levels of ethanol, causing his blood to become more acidic
c)
His muscles may have produced toxic levels of ethanol, causing his blood to become more basic
d)
His muscles may have produced toxic levels of lactic acid, causing his blood to become more basic
62.
Which of the following statements is true regarding the equation C6H12O6 + 6O2 -> 6CO2 + 6H2O + energy
a)
The oxygen atoms in both CO2 and H2O are electronegative,and glucose is considered a reducing agent
b)
In the production of CO2 from glucose, the oxygen atoms lose electrons and the carbon atom is oxidized
c)
Glucose could be considered a reducing agent
d)
The oxygen atoms in both CO2 and H2O are electronegative
63.
In what organelle is pyruvate oxidation carried out in a cell?
a)
Mitochondrion
b)
Endoplasmic reticulum
c)
Nucleus
d)
Chloroplast
64.
Due to the pumping action of the electron transport chain, protons have a high concentration in the ____ and a low concentration in the ____.
a)
Inter membrane space; mitochondrial matrix
b)
mitochondrial matrix; extracellular fluid
c)
mitochondrial matrix; inter membrane space
d)
intermembrane space; cytoplasm
65.
Some present-day bacteria use a system of anaerobic respiration characterized by an electron transport chain analogous to that found in aerobic organisms. Which of the following correctly characterizes the anaerobic electron transport chain?
a)
It uses oxygen as a final electron acceptor
b)
It is embedded in the outer mitochondrial membrane rather than the inner mitochondrial membrane
c)
It establishes a proton gradient between the cytoplasm and the extracellular fluid
d)
It establishes a proton gradient between the intermembrane space and the cytoplasm
66.
Which of the following statements is true regarding triacylglycerols?
a)
Triacylglycerols have no structural similarities to glycerol
b)
Like glycogen, triacylglycerols are stored primarily in the liver
c)
ATP is derived from triacylglycerols through beta-oxidation and substrate-level phosphorylation
d)
Triacylglycerols can be used to generate acetyl-CoA
67.
In cellular respiration, glucose is _____ to CO2 and oxygen is ____ to water.
a)
reduced; oxidized
b)
oxidized; reduced
c)
phosphorylated; deoxygenated
d)
oxidized; oxidized
68.
Which of the following does not occur during the third phase of glycolysis?
a)
Pyruvate production
b)
Oxygen consumption
c)
ATP synthesis
d)
The transfer of high-energy electrons to NAD+
69.
Recall that the citric acid cycle start with a four-carbon molecule, but that most of its intermediates are molecules that contain six carbons. How is this possible?
a)
Though the reaction of malate and fumarate
b)
Through the reaction of acetyl-CoA and oxaloacetate
c)
Though the reaction of malate and oxaloacetate
d)
Though the reaction of succinate and succinyl-CoA
70.
When an electron is transferred from NADH to CoQ, NADH is ____ and CoQ is ____.
a)
reduced; oxidized
b)
oxidized; reduced
c)
reduced; reduced
d)
oxidized; oxidized
71.
In the absence of oxygen, fermentation:
a)
regenerates NAD+ from the reduction of pyruvate
b)
regenerates NAD+ from the oxidation of pyruvate
c)
generates ATP from the oxidation of pyruvate
d)
generates ATP from the reduction of pyruvate
72.
_____ is found in animals, and possesses a large, central protein. ____ is found in plants and lacks a central protein.
a)
starch; glycogen
b)
glycogen; starch
c)
glycogen; glycogen
d)
starch; starch
73.
The chemical bonds of carbohydrates and lipids have high potential energy because:
a)
They are easy to hydrolyze
b)
They are strong reducing agents
c)
They are strong oxidizing agents
d)
Many of these bonds are C-C and C-H bonds
74.
Imagine that you exhale after a deep breath. Which of the following are you not releasing?
a)
CO2
b)
Waste products of glycolysis
c)
Waste products of pyruvate oxidation
d)
Waste products of the citric acid cycle
75.
Although cellular respiration is typically thought of as an aerobic process, glycolysis itself is actually anaerobic.
a)
True
b)
False
76.
Imagine that a eukaryotic cell carries a mutation impairing its ability to phosphorylate glucose during glycolysis. What is a likely result of this mutation?
a)
More pyruvate would be formed at the end of glycolysis
b)
Because phosphorylation stabilizes glucose, glucose would spontaneously form pyruvate
c)
Without the phosphorylation of glucose, glycolysis would consist entirely of exergonic reactions
d)
Glucose could move out of the cell, slowing cellular respiration
77.
During what phase of glycolysis is NADH formed?
a)
During phase 1, when fructose 1, 6-biphosphate is formed
b)
During phase 2, when glyceraldehyde3-phosphate is formed
c)
During phase 3 when pyruvate is finally formed
d)
During phase 3, when glyceraldehyde3-phosphate is phosphorylated
78.
During pyruvate oxidation, pyruvate is broken down into CO2 and an acetyl group. The CO2 is:
a)
less oxidized than the acetyl group
b)
more reduced than the acetyl group
c)
more energetic than the acetyl group
d)
less energetic than the acetyl group
79.
Animal cells have mitochondria but no chloroplasts, while plant cells have chloroplasts but no mitochondria.
a)
True
b)
False
80.
Where does photosynthesis occur?
a)
Chloroplast
b)
Mitochondria
c)
Cytoplasm
81.
Where does aerobic cellular respiration occur?
a)
Chloroplast
b)
Mitochondria
c)
Cytoplasm
82.
Where does glycolysis take place?
a)
Chloroplast
b)
Mitochondria
c)
Cytoplasm
83.
Where does ATP synthesis take place?
a)
Chloroplast and Mitochondria
b)
Mitochondria
c)
Cytoplasm and Mitochondria
d)
Cytoplasm, Mitochondria, and Chloroplast
84.
Where are electron transport chains located?
a)
Chloroplast and Mitochondria
b)
Chloroplast, Mitochondria, and Cytoplasm
c)
Cytoplasm
d)
Mitochondria
85.
Where does NADH act as an electron carrier?
a)
Mitochondria and Cytoplasm
b)
Chloroplast and Cytoplasm
c)
Cytoplasm
d)
Mitochondria and Chloroplast
86.
The products of the Calvin cycle are used to assemble larger sugars in the:
a)
Cytoplasm
b)
Stroma
c)
Matrix of the mitochondria
d)
Lumen of the thylakoids
87.
Carbon enters the Calvin cycle in the form of:
a)
CO2
b)
Glucose
c)
RuBP
d)
3-PGA
88.
Protons in a chloroplast flow through an ATP synthase from the:
a)
Cytoplasm to the inter membrane space
b)
Thylakoid lumen to the stroma
c)
Stroma to the intermembrane space
d)
Stroma to the thylakoid lumen
89.
Which one of the following is NOT a product when photosystem II oxidizes a water molecule?
a)
Carbon dioxide
b)
Electrons
c)
Protons
d)
Oxygen
90.
The ATP generated by a photosynthetic electron transport chain can be used in the _____ step(s) of the Calvin cycle.
a)
Carboxylation
b)
Reduction
c)
Reduction and regeneration
d)
Carboxylation, reduction, and regeneration
91.
In which of the following is part of the preparatory phase of glycolysis?
a)
Phosphorylation of a 3-carbon molecule
b)
Cleavage of a 6-carbon molecule into two 3-carbon molecules
c)
Synthesis of ATP
d)
Phosphorylation of a 6-carbon molecule
92.
Once molecules of pyruvate enter the mitochondria, how many electron carriers (NAD+ or FAD) are reduced per original molecule of glucose?
a)
4
b)
5
c)
8
d)
10
93.
If you added additional protons to the thylakoid lumen of the chloroplast, would you expect ATP synthesis to:
a)
Increase
b)
Decrease
c)
Remain the same
94.
Organisms with only one photosystem cannot:
a)
Oxidize H2S
b)
Reduce H2O
c)
Produce O2
d)
Reduce CO2
95.
Which of the following is needed directly to produce both triose phosphates and RuBP
a)
O2
b)
ATP
c)
Rubisco
d)
NADPH
96.
The products of the Calvin cycle are three-carbon sugars.
a)
True
b)
False
97.
In the Calvin cycle, NADPH is:
a)
Reduced
b)
Oxidized
c)
Phosphorylated
d)
None of the choices are correct
98.
All cells able to carry out photosynthesis have:
a)
Mitochondria
b)
Chloroplasts, mitochondria, and a plasma membrane
c)
A plasma membrane
d)
Chloroplasts and mitochondria
99.
All photosynthetic bacteria possess two functionally distinct photosystems.
a)
True
b)
False
100.
In the chloroplasts of plant cells, the absorption of light energy and the movement of electrons along an electron transport chain occurs in the ___ and the synthesis of carbohydrates takes place in the ____.
a)
Inner membrane; stroma
b)
Thylakoids; stroma
c)
Inner membrane; matrix
d)
Thylakoids; matrix
101.
Which of the following are rubisco substrates?
a)
CO2, O2, and RuBP
b)
CO2
c)
RuBP
d)
CO2 and O2
102.
NADH production in photosynthesis requires:
a)
light and protons
b)
electrons
c)
light, protons, and electrons
d)
light
103.
The Calvin cycle is a relatively constant process, the rate of which is independent of factors such as temperature and nitrogen concentration.
a)
True
b)
False
104.
Which step of the Calvin cycle would be affected first by a lack of NADPH?
a)
reduction
b)
carboxylation
c)
regeneration
d)
all choices are correct
105.
The first photosynthetic organisms probably used chlorophyll as the primary light absorbing pigment.
a)
True
b)
False
106.
From its ground state, photosystem II can:
a)
Emit light energy
b)
Absorb light energy
c)
Pass electrons to photosystem I
d)
Pulls electrons from H2O
107.
For every six CO2 molecules incorporated into carbohydrate molecules, how many triose phosphates can be exported from the chloroplast?
a)
1
b)
2
c)
6
d)
12
108.
During their experiments with chlorella, Calvin and Benson found no free glucose. Why do you think this is?
a)
Green algae do not respire when illuminated
b)
Glucose is stored as starch
c)
Glucose takes too long to synthesize
d)
Glucose is an isomer of fructose
109.
The Z scheme refers to:
a)
Proton translocation
b)
The path of electrons between photosystem II and cytochrome b6f
c)
The changes in the energy level of electron donors during the photosynthetic electron transport chain
d)
Electron transport
110.
Photosystem II and photosystem I differ in:
a)
H+ production, and electron donors and acceptors
b)
Electron donors and acceptors
c)
H+ production
d)
H+ production and electron donors
111.
Photosystem I is a ____ than photosystem II.
a)
weaker oxidant and a stronger reductant
b)
stronger reductant
c)
stronger oxidant and a stronger reductant
d)
weaker oxidant
112.
Collectively, most photosynthesis carried out in the ocean is performed by single-celled organisms as opposed to large, multicellular marine plants.
a)
True
b)
False
113.
Which of the following is thought to be the first group of organisms to use water as an electron donor in photosynthesis?
a)
aquatic plants
b)
algae
c)
land plants
d)
cyanobacteria
114.
Which of the following are produced directly as a result of the movement of electrons through the photosynthetic electron transport chain?
a)
oxygen and carbohydrates
b)
ATP and NADPH
c)
carbohydrates and ATP
d)
water and carbohydrates
115.
Which of the following compounds is required for the carboxylation step of the Calvin cycle?
a)
NADPH
b)
RuBP
c)
ATP and NADPH
d)
ATP
116.
Which of the following is responsible for the transport of electrons between photosystem II and photosystem I?
a)
NADPH
b)
NADP+
c)
Water
d)
Cytochrome b6f
117.
ATP, NADPH, and NADH contain stored energy used by plant cells. Which of these molecules provides the energy that is stored in carbohydrate during the Calvin cycle?
a)
NADH
b)
NADPH
c)
ATP
118.
Cyclic electron transport enhances ATP production because:
a)
cyclic electron transport is more energy efficient than linear electron transport
b)
electrons are transferred from ferredoxin to plastoquinone
c)
photosystem I pumps more protons
d)
ATP production increases
119.
In addition to chloroplasts, which of the following organelles of eukaryotic cells is believed to have originated by endosymbiosis?
a)
mitochondria
b)
ribosomes
c)
lysosomes
d)
endoplasmic reticulum
120.
Where does the oxygen come from that is produced as a by-product of photosynthesis?
a)
from the Calvin cycle
b)
from the breakdown of water
c)
from the breakdown of carbohydrates
d)
from the reduction of CO2
121.
Which of the following best describes the benefit to early photosynthetic organisms gained by having two different photosystems in one cell?
a)
They could thrive in places where there was little or almost no light
b)
They could use water as an electron donor
c)
These organisms produced carbohydrates at twice the rate of organisms with a single photosystem
d)
They produced oxygen
122.
Paraquat is a herbicide that blacks the transfer of electrons from photosystem I to NADPH. Mechanistically, paraquat is effective because it:
a)
increases the formation of reactive oxygen species
b)
prevents the reduction of NADPH
c)
prevents the formation of reactive oxygen species
d)
increases cyclic electron transport, which does not produce NADPH
123.
A researcher is carrying out an experiment where she labels a protein with a fluorescent tag (so she can visualize its location in a cell), and introduces this tagged protein into the lumen of a single thylakoid. She observes her treated cells periodically, and notices that the labeled protein can move between grant, but is never observed in the stroma. What can she deduce?
a)
This protein cannot easily diffuse through the thylakoid membrane
b)
The protein likely travels through a common lumen shared by thylakoid membranes and grant, and cannot easily diffuse through the thylakoid membrane
c)
This protein can easily transfer between the inner and outer mitochondria membranes
d)
This protein likely travels between different thylakoid membranes by moving through the stroma, but its movement through the stroma is very brief
124.
Which of the following statements is true regarding reactive oxygen species?
a)
Reactive oxygen species are formed when excess electrons are added to O2
b)
They are likely to form if NADP+ is rare in a cell
c)
They can be neutralized by antioxidants and can form when O2 is exposed to excess light energy
d)
All choices are correct
125.
Low temperatures slow the activity of rubisco but enhance its ability to select CO2 over O2. Low temperatures thus:
a)
increase photosynthesis rates
b)
decrease phoriespiration rates
c)
increase the production of reactive oxygen species
d)
increase photorespiration rates
126.
Over evolutionary time, photosynthesis has, in effect, introduced challenges to itself by producing an oxygen atmosphere because:
a)
rubisco is an oxygenase and O2 is a strong oxidant
b)
rubisco is an oxygenase and O2 is a strong reductant
c)
rubisco is a carboxylase
d)
O2 is a strong oxidant
127.
The regeneration of RuBP typically limits the rate of photosynthesis under low light intensities. This is because:
a)
RuBP regeneration requires ADP
b)
RuBP regeneration requires ATP
c)
RuBP regeneration is part of the "dark reactions"
d)
Photosynthesis occurs only in high light
128.
How many molecules of NADPH are required for 12 molecules of RuBP to be carboxylated by rubisco?
a)
36
b)
24
c)
10
d)
None of the choices are correct
129.
Chemicals called uncouplers can make membranes permeable to small molecules and ions. What effect might un-couplers have on photosynthesis?
a)
increased ATP production because cyclic electron transport would increase
b)
decreased ATP production because the proton gradient would decrease
c)
decreased ATP production because the proton gradient would increase
d)
decreased NADPH production because the proton gradient would increase
130.
Which of the following statements is true regarding the Calvin cycle?
a)
The Calvin cycle is considered a "dark" reaction, because it is not directly related to photosynthesis
b)
The Calvin cycle is a carefully regulated process because excess starch can be toxic to plant cells
c)
The Calvin cycle uses a rare (and thus "rate-limiting") enzyme called rubisco
d)
None of the answers are correct
131.
With the endosymbiotic hypothesis in mind, what structure within modern-day chloroplasts is likely derived from the plasma membrane of ancestral cyanobacteria that took up residence within a eukaryotic cell?
a)
inner membrane
b)
stroma
c)
thylakoid membrane
d)
grana
132.
In the lab you isolate a chlorella mutant that is unable to switch xanthophyll pigment into the inactive, non-heat-dissipating form. If you released that mutant into a small pond shaded by trees, would the mutation spread, and why?
a)
No, because the light absorbed by chlorophyll would be released as heat and thus not used to make ATP or NADPH
b)
Yes, because the heat released by the xanthophyll would warm up the cells and enhance photosynthesis
c)
No, because the xanthophyll prevent the production of reactive oxygen species
d)
No, because mutations never spread in nature
133.
Which of the following statements is true regarding the earliest photosynthetic organisms on Earth?
a)
Given the abundance of H2O on early Earth, these organisms used H2O as an electron donor
b)
The organisms likely used molecules other than water (ex. H2S) as electron donors
c)
These organisms likely used both inorganic molecules and water as electron donors
d)
These organisms likely possessed two photosystems
134.
Which of the following is true concerning the Calvin cycle and the light-harvesting reactions of photosynthesis?
a)
They take place in different organelles
b)
They take place in different compartments of the same organelle
c)
They take place in different types of cells in the plant
d)
None are correct
135.
With the endosymbiotic hypothesis in mind, which of the following within modern day chloroplasts is likely derived from the cytoplasm of ancestral cyanobacteria that took up residence within a eukaryotic cell?
a)
stroma
b)
grana
c)
thylakoid lumen
d)
inner chloroplast membrane
136.
Which of the following is NOT responsible for amplifying the signal in a cell responding to adrenaline signaling?
a)
One molecule of adenylyl cyclase can produce many molecules of cAMP
b)
One adrenaline molecule can bind to and activate many receptors simultaneously
c)
One molecule of protein kinase A can phosphorylate and activate many target proteins
d)
One activated receptor can activate many G proteins
137.
A protein on a cell surface that binds to a signaling molecule is an example of which of the following elements of cellular communication?
a)
a responding cell
b)
a signaling molecule
c)
a signaling cell
d)
a receptor protein
138.
Platelet-derived growth factor (PDGF) is a signaling molecule that functions in which of the following types of cell signaling?
a)
contact-dependent
b)
endocrine
c)
autocrine
d)
paracrine
139.
What is the key difference between cell signaling by a cell-surface receptor and cell signaling by an intercellular receptor?
a)
Cell-surface receptors typically bind to signaling molecules that are smaller than those bound by intracellular receptors
b)
Cell-surface receptors bind to a specific signaling molecule; intracellular receptors bind to any signaling molecule
c)
Cell-surface receptors bind polar signaling molecules; intracellular receptors bind non polar signaling molecules
d)
Signaling molecules that bind to cell-surface receptors lead to cellular responses restricted to the cytoplasm; signaling molecules that bind to intracellular receptors lead to cellular responses restricted to the nucleus
140.
Kohler and Lipton first discovered platelet-derived growth factor by observing that fibroblasts:
a)
could not grow in cell culture without the addition of purified red blood cells
b)
grew better in cell culture when blood serum was added to the growth medium instead of blood plasma
c)
could not grow in cell culture without adding bovine blood serum to the growth medium
d)
could not grow and repair wounding without the action of platelets
141.
Which of the following is TRUE about the Delta protein?
a)
Delta directly signals to a Notch transmembrane protein in adjacent cells and directs the cells to differentiate into glial cells
b)
Delta is a transmembrane protein found in embryonic brain cells
c)
Delta is produced by embryonic stem cells as they differentiate into neurons in the brain
d)
All choices are correct
142.
Why do the functions of many receptor kinases depend on the fluid nature of the plasma membrane?
a)
Phosphorylation requires a fluid membrane
b)
The receptor monomers must move together and dimerize to be activated
c)
The generation of cAMP requires a fluid membrane
d)
Binding of ligand to the receptor requires fluid membrane
143.
Which of the following types of cellular activities can be a response to cell signaling?
a)
Gene expression patterns are changed
b)
Cell division is triggered
c)
Enzyme activities are changed
d)
All choices are correct
144.
Which type of receptor is involved in rapid responses of muscle cells and neurons?
a)
ligand-gated ion channel
b)
receptor kinase
c)
G protein-coupled receptor
d)
intracellular receptor
145.
Phosphate groups play a key role in receptor kinase activation by:
a)
activating receptor kinase activity
b)
providing binding sites to recruit and activate signal-transduction proteins
c)
activating the dimerization of the receptor kinase proteins in the membrane
d)
activating the receptor, so that the receptor is capable of binding its signal
146.
What is the 1st law of thermodynamics?
a)
Energy is present in the form of ATP
b)
Chemical reactions always increase the disorder in universe
c)
Energy cannot be created or destroyed, only change form.
147.
What is a spontaneous (exergonic) reaction?
a)
A reaction that requires an input of energy
b)
A reaction that releases energy
148.
An exergonic reaction can provide the energy needed to do endergonic reactions.
a)
True
b)
False
149.
What is a catabolic reaction?
a)
A reaction that requires energy and decreases entropy
b)
A reaction that releases energy and increases entropy
150.
Which of the following is true of anabolism?
a)
Builds up molecules
b)
Breaks down molecules
151.
How do enzymes work?
a)
they increase the activation energy of a reaction
b)
they keep a constant activation energy of a reaction
c)
they lower the activation energy of a reaction
152.
Plants can be classified as which of the following?
a)
photoheterotroph
b)
chemoautotroph
c)
chemohetertroph
d)
photoautotroph
153.
Which of the following is not a step of cellular respiration?
a)
glycolysis
b)
pyruvate oxidation
c)
citric acid cycle
d)
calvin cycle
154.
How many ATP (net gain) are produced in cellular respiration?
a)
28
b)
32
c)
4
d)
18
155.
Glycolysis requires oxygen.
a)
True
b)
False
156.
What are the inputs of photosynthesis?
a)
carbon dioxide and water
b)
oxygen and water
c)
glucose and oxygen
d)
water and glucose
157.
What are the outputs of photosynthesis?
a)
water and oxygen
b)
glucose and water
c)
glucose and oxygen
d)
carbon dioxide and water
158.
Concerning Photosynthesis: Water is _____and becomes oxygen.
a)
oxidized
b)
reduced
159.
Concerning Photosynthesis: Carbon dioxide is _____ and becomes glucose.
a)
oxidized
b)
reduced
160.
The calvin cycle requires sunlight to proceed.
a)
True
b)
False
161.
Which type of cellular communication involves two cells communicating over long distances?
a)
paracrine signaling
b)
autocrine signaling
c)
endocrine signaling
d)
juxtacrine signaling
162.
Which type of cellular signaling involves two cells touching each other?
a)
juxtacrine
b)
endocrine
c)
paracrine
d)
autocrine
163.
What is another name for a signaling molecule?
a)
responder
b)
receptor
c)
ligand
d)
z scheme
164.
Do the bonds in phosphate groups have high or low potential energy?
a)
High
b)
Low
165.
Protein structure does not equal function.
a)
True
b)
False
166.
Which type of inhibition changes the shape of an enzymes active site?
a)
Non-competitive
b)
Competitive
167.
What is the final electron acceptor in the electron transport chain? (cellular respiration)
a)
glucose
b)
oxygen
c)
water
d)
carbon dioxide
168.
What does glycolysis produce?
a)
oxygen
b)
carbon
c)
glucose
d)
pyruvate
169.
What type of reaction does not require oxygen?
a)
aerobic
b)
anaerobic
170.
Which step of cellular resp. produces the most ATP?
a)
glycoysis
b)
oxidative phosphorylation
c)
citric acid cycle
d)
pyruvate oxidation
171.
Acetyl-CoA is the start of which step of cellular resp.?
a)
glycolysis
b)
pyruvate oxidation
c)
citric acid cycle
d)
oxidative phosphorylation
172.
What is phosphofructokinase?
a)
an enzyme that processes sugars from fruit
b)
an enzyme that phosphorylates fructose-6 phosphate
173.
In photorespiration RUBISCO binds to carbon dioxide instead of oxygen.
a)
true
b)
false
174.
What is Z-scheme?
a)
the energy trajectory of a proton
b)
the energy trajectory of a neutron
c)
the energy trajectory of an electron
175.
Photosystem one is the electron acceptor.
a)
True
b)
False
176.
How many membranes does the chloroplast structure have?
a)
1
b)
2
c)
3
d)
4
177.
Where does a ligand bind to?
a)
ligand-binding site
b)
a cell
c)
another ligand
178.
When is the G-protein active?
a)
in its GDP form
b)
in its GTP form
179.
Reduction is the_____.
a)
loss of electrons
b)
gain of electrons
180.
In photosynthesis NADP+ is reduced to what?
a)
NAD
b)
NADH
c)
NAD+
d)
NADPH
181.
Triose phosphate is the sugar that is important in the Calvin Cycle.
a)
true
b)
false
182.
In G protein-coupled signaling, the receptor undergoes a conformational change.
a)
true
b)
false
183.
When can ions pass through an ion channel?
a)
when the ligand binds the ligand binding site, channel opens
b)
an ion can always pass through the ion channel
c)
before a ligand binds the ligand binding site, channel opens
184.
Ras in the map-kinase pathway works the same as the alpha subunit in G protein signaling.
a)
true
b)
false
185.
For receptor kinases what happens when the protein is activated or turned on?
a)
no phosphate group, dimerizes receptor
b)
phosphate group present, dimerizes receptor
c)
no phosphate group, no dimerization
d)
phosphate group present, no dimerization
186.
How many subunits does the G protein have from the examples in lecture?
a)
1
b)
2
c)
3
d)
4
187.
Is cAMP a secondary messenger?
a)
Yes
b)
No
188.
What is the end activity of the MAP kinase pathway?
a)
gene transcription
b)
gene translation
189.
How would the signal of a G protein-coupled receptor without ligand be affected if you made an enzyme that converted GDP to GTP constitutively?
a)
it wouldn't be affected; there is no ligand, thus no signal
b)
it wouldn't be affected; the ligand would be unable to bind due to the conformational change
c)
the G protein would be active but unable to signal due to lack of ligand
d)
the G protein would be active and signaling despite the lack of ligand
100 %
