Download Cellular Respiration

Exam 3 Version 1
October 20th, 2016
Name: ___________________________
Dr. A. Pimentel
NetID: ____________________________
Instructions:
1- Select the most correct answer.
2- Use pencil to mark your responses in the answer sheet.
3- You can mark your booklet if you want but only the answers sheet will be graded.
4- Have your Cat Card ready when you hand the exam back to us.
5- Each question of this exam has a value of 4 points.
6- The exam has a total possible score of 160 points, but the maximum score will be
capped at 150 points.
Cellular Respiration
1- Cellular respiration occurs in different regions/compartments of the cell. From the following
regions/compartments, select the one in which the environment is most acidic:
A. Cytoplasm
B. Matrix of the mitochondria
C. Intermembrane space of the mitochondria
D. Golgi Apparatus
E. Rough ER
2- Considering the steps of oxidative phosphorylation, which of the following statements would
most likely be correct?
A. Lower the pH (closer to zero) in the intermembrane space, higher the rate of ATP
production.
B. Higher the pH (closer to 14) in the intermembrane space, higher the rate of ATP
production.
C. Lower the concentration of oxygen, higher the rate of ATP production
D. Lower the concentration of glucose, higher the rate of the ATP production
3- Antimycin A is an antibiotic that permanently inhibits the oxidation of ubiquinone (CoQ). This
chemical is used as a piscicide to kill some invasive species of fish. Select the statement that
best explains how Antimycin A affects cellular respiration. .
A. Complex I and II remain reduced, Complex III and IV remain oxidized.
B. Complex I and II remain oxidized, Complex III and IV remain reduced.
C. Complex I and IV remain oxidized, complex II and IV remain reduced.
D. Complex I and IV remain reduced, complex II and IV remain oxidized.
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4- The reaction above is an example of a(n):
A. Anabolic reaction
B. Catabolic reaction
C. Endergonic reaction
D. Exergonic reaction
E. Coupling reaction
5- Which of the following processes in cellular respiration involves formation of ATP via substrate
level phosphorylation in the mitochondrial matrix?:
A. Oxidative phosphorylation
B. Glycolysis
C. Pyruvate oxidation
D. Citric acid cycle
E. More than one answer is correct
6- The figure below shows a step of the Krebs cycle. Select the answer that correctly describes
the process taking place to produce oxaloacetate.
A.
B.
C.
D.
E.
Malate is reduced and NAD+ is oxidized.
Oxaloacetate is reduced and NADH is oxidized.
Malate is oxidized and NAD+ is reduced.
Malate and Oxaloacetate are reduced.
Oxaloacetate and NAD+ are reduced.
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7- During heavy workout in humans, the muscles are deprived of oxygen. What occurs in the
mitochondria of muscle cells during the workout?
A. NAD+ oxidizes pyruvate to ethanol
B. NADH reduces pyruvate to lactic acid
C. NADH oxidizes glucose to lactic acid
D. NAD+ reduces pyruvate to ethanol
E. NADH reduces acetaldehyde to ethanol
8- The step in cellular respiration in which most of covalent bonds from the the glucose molecule
are oxidized:
A. Oxidative phosphorylation
B. Glycolysis
C. Pyruvate oxidation
D. Citric acid cycle
E. Fermentation
9-
Assertion
The gradient of hydrogen ions created in the
inter-membrane space is built when protein
complexes I, III and IV of the electron
transport chain are reduced.
A.
B.
C.
D.
E.
Reason
Because
Electrons move through
the ETC as long as water
molecules are present in
the cell.
Assertion is true; Reason is true; Reason is the correct explanation
Assertion is true; Reason true; Reason is NOT the correct explanation
Assertion is true; Reason is false
Assertion is false; Reason is true
Assertion is false; Reason is false
10- Which of the following molecules will activate cellular respiration when it is found in high
concentration in the mitochondria?
A. NAD+
B. NADH
C. ATP
D. ADP
E. FADH
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11-
Assertion
NADH produces more ATP
molecules than FADH2.
A.
B.
C.
D.
E.
Reason
Because
Following the citric acid cycle but
before the electron transport chain
and oxidative phosphorylation, most
of the energy from the original
glucose molecule is found in NADH
Assertion is true; Reason is true; Reason is the correct explanation
Assertion is true; Reason true; Reason is NOT the correct explanation
Assertion is true; Reason is false
Assertion is false; Reason is true
Assertion is false; Reason is false
12- Fill in the correct sign + (positive) or - (negative) for the overall process of cellular respiration.
__ ΔG, __ ΔH, __ ΔS
A. +, +, +
B. -, +, C. -, -, +
D. +, -, E. -, -, 13- ATP is generated using several mechanisms within the cell. Which of the following is true?
A. Substrate level phosphorylation produces more ATP relative to oxidative phosphorylation
B. Oxidative phosphorylation produces more ATP relative to substrate level phosphorylation
C. Oxidative phosphorylation and substrate level phosphorylation produce similar amounts
of ATP
D. Fermentation produces more ATP than cellular respiration
14- In glycolysis, why is ATP invested into glucose?
A. To increase its potential energy
B. To destabilize the glucose molecule for phase 2
C. To stabilize the glucose molecule
D. A and B
E. B and C
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The Cell
15- Correctly place the following steps involved in rough ER protein production in sequential
order:
1.
2.
3.
4.
5.
The SRP binds to the SRP receptor on the ER membrane.
The SRP dissociates and protein synthesis resumes.
The SRP receptor brings the ribosome to a transmembrane channel.
The growing polypeptide chain is threaded through the channel.
The signal-recognition particle (SRP) binds to a signal sequence in the amino-terminal
end of the growing polypeptide and halts translation.
A.
B.
C.
D.
E.
3,2,1,4,5
4,3,2,1,5
5,1,3,2,4
3,1,5,2,4
5,4,2,1,3
16- Which of the following statements is FALSE?
A. Both plant and animal cells contain mitochondria
B. Both plant and animal cells contain chloroplasts
C. Both plant and animal cells contain the golgi apparatus
D. Both plant and animal cells contain smooth ER
E. Both plant and animal cells contain cytoskeleton
17- Which of the following statements about kinesin is FALSE?
A. Each step that kinesin takes requires ATP to be hydrolyzed
B. Kinesin moves towards the positive (+) end of the microtubule
C. Kinesin transports vesicles between compartments inside the cell
D. Kinesin is responsible for pseudopodia (cell crawling) in animal cells
E. The tail of the kinesin protein attaches to the transport vesicle as the head of kinesin
protein takes steps
18- Which of the following cytoskeletal filaments is CORRECTLY matched with its function?
A. Actin filaments - cell division in animal cells
B. Intermediate filaments - movement of organelles
C. Microtubules - anchoring nucleus
D. Microfilaments - maintain cell shape by resisting compression
E. Intermediate filaments - growth of plant cell walls
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19- Cystic fibrosis is a disease that is caused by a mutation in the CFTR gene. CFTR gene
encodes for the CFTR transmembrane protein. This mutation can lead to many complications in
humans such as thickening of mucus and frequent respiratory infections. Where is the CFTR
protein synthesized?
A. Smooth ER
B. Rough ER
C. Golgi apparatus
D. Nucleus
E. Cytoplasm
20- In a research lab, you are working with a specific enzyme called Pimentase. The structure of
Pimentase has two sites in which molecules can bind. You add an unknown substance to the
reaction and the reaction rate decreases. After further investigation, you determine that the
unknown substance binds away from the active site. What could be the reason for observing
reduced reaction rate?
A. The unknown substance is competitively inhibiting Pimentase
B. The unknown substance allows for better binding of the substrate to Pimentase
C. The unknown substrate decreases the activation energy of the reaction
D. The unknown substrate does not affect the reaction mechanism
E. The unknown substance is allosterically inhibiting Pimentase
21- Hexokinase is an enzyme that catalyzes the first reaction of glycolysis. Hexokinase
hydrolyzes ATP and phosphorylates glucose to form glucose 6-phosphate. Where will
Hexokinase be synthesized?
A. Smooth ER
B. Rough ER
C. Golgi apparatus
D. Mitochondria
E. Cytoplasm
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22- The picture above is acquired through electron microscopy of the human testes. Human
testes produce male sex hormone testosterone. Testosterone is a steroid hormone that is
responsible for development of the male reproductive system. Which of the following organelles
will be found abundantly in the cells of human testes?
A. Nucleus
B. Rough ER
C. Smooth ER
D. Lysosomes
E. Mitochondria
23- The cellular structure that resist turgor pressure is:
A. Cell membrane
B. Cell wall
C. Chloroplast
D. Smooth ER
E. Rough ER
24- Select the statement that is correct about eukaryotic cells:
A. Organelles allow incompatible enzymes to co-exist in the same organelle without
damaging the cell.
B. Organelles increase the efficiency of the biochemical reactions that occurs in the cell.
C. Microfilaments are used as cellular railroad tracks to move vesicles in the cell.
D. Kinesin proteins walkthrough microfilaments.
E. Glycolysis occurs inside of mitochondria.
25- Which of the following organelles likely contains the largest amount of pump proteins?
A. Rough ER
B. Smooth ER
C. Golgi Apparatus
D. Lysosome
E. Ribosomes
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26- The DNA molecules of eukaryotic cells are protected by the nuclear membrane, which
prevents certain enzymes from entering and damaging this vital cellular component. The
information contained in DNA needs to travel to the cytoplasm because it is the place where
proteins are synthesized. How does the information contained in the DNA molecule reach the
cytoplasm even though this molecule can’t leave the nucleus?
A. The ribosomes bring the information to the cytoplasm where it is used to synthesize
proteins.
B. The mRNA molecules bring the information to the cytoplasm where it is used to
synthesize proteins.
C. The rRNA brings the information to the cytoplasm where it is used to synthesize proteins.
D. The tRNA brings the information to the cytoplasm where it is used to synthesize proteins.
E. The rough ER brings the information to the cytoplasm where it is used to synthesize
proteins.
27- Which of the following structures are found in both eukaryotic and prokaryotic cells?
A. Nucleus
B. Mitochondria
C. Ribosomes
D. Golgi apparatus
E. Peroxisomes
28- Reactive oxygen species are a byproduct of the mitochondrial electron transport chain during
aerobic respiration. If these reactive oxygen species are not managed appropriately, substantial
DNA damage can occur. What is one of the organelles responsible for reducing reactive oxygen
species within the cell?
A. Lysosome
B. Peroxisome
C. Mitochondria
D. Golgi apparatus
E. Smooth ER
29- Which of the following eukaryotic cell structures plays a role in protein trafficking and sorting?
A.
B.
C.
D.
E.
Mitochondria
lysosomes
the endoplasmic reticulum
the Golgi apparatus
vacuoles
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Energy and enzymes
30- Which component of ATP contributes to its high potential energy?
A. Ribose
B. Adenine
C. Phosphate groups
D. None of the above
31- AMP is an indicative of low energy charge within the cell. How many phosphate groups need
to be added to AMP to regenerate ATP?
A. One
B. Two
C. Three
D. None of the above
32- Enzymes require an optimal environment in order to function properly. A drastic increase in
temperature will do what to the enzyme?
A. Increase the reaction velocity of the enzyme catalyzed reaction
B. Increase in the number of substrate binding to enzyme
C. No change in the reaction velocity of enzyme catalyzed reaction
D. Denature the enzyme
E. None of the above
33- Select the statement that is correct about the glycolysis step of cellular respiration
I- Overall the ∆G of cellular respiration is negative
II- Overall the ∆G of cellular respiration is positive
III- Overall glycolysis is an endergonic reaction
IV- Overall glycolysis is an exergonic reaction
V- Overall the ∆S of the glycolysis is negative
VI- Overall the ∆S of glycolysis is positive
A.
B.
C.
D.
E.
II, III and V are correct
I, IV and VI are correct
I, II and V are correct
I, II and III and VI are correct
II, III and IV are correct
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34- In the chemical reaction shown above, which is the point at which both old and new bonds
are present?
A.
B.
C.
D.
E.
Reactants
I
II
III
Product
35- Which of the following statement is correct about the chemical reaction shown above?
A. The ∆G is negative
B. The reactants have less energy than the products.
C. The ∆S is negative
D. This is an endergonic reaction
E. The reaction does not have an activation energy.
36- The Energy that is required to create the state in which old and new bonds are kept together
is represented in this graph by:
A.
B.
C.
D.
E.
Reactants
I
II
III
Product
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37-
Assertion
Every time a ATP molecule is hydrolyzed into
ADP and inorganic phosphate, energy from
the ATP molecule is destroyed.
A.
B.
C.
D.
E.
Reason
Because
The hydrolysis of ATP
molecules is an
exergonic reaction.
Assertion is true; Reason is true; Reason is the correct explanation
Assertion is true; Reason true; Reason is NOT the correct explanation
Assertion is true; Reason is false
Assertion is false; Reason is true
Assertion is false; Reason is false
38- After analyzing the figure above, you can conclude that B is ________________ , A is the
___________ , D is the __________ and that the activity of this enzyme is regulated by
____________.
A.
B.
C.
D.
E.
39-
Allosteric site, active site, product D, competitive inhibition
Active site, Allosteric site, substrate, allosteric inhibition.
Substrate, Allosteric site, allosteric inhibitor, competitive inhibition
Hydrophobic site, hydrophilic site, substrate, allosteric inhibition
More than one answer is correct.
Assertion
When an enzyme is added to a reaction, it
accelerates the rate by lowering the activation
energy.
Reason
Because
Once the enzyme is
added to the reaction, it
decreases the ∆G of the
reaction.
A.
B.
C.
D.
E.
Assertion is true; Reason is true; Reason is the correct explanation
Assertion is true; Reason true; Reason is NOT the correct explanation
Assertion is true; Reason is false
Assertion is false; Reason is true
Assertion is false; Reason is false
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40- A biologist working in a lab adds a compound to a solution that contains an enzyme and its
substrate. This compound binds to the enzyme and decreases the rate at which the enzyme
converts substrate to product. However, this decrease can be overcome by increasing the
concentration of substrate to the reaction mix. Therefore, which of the following is TRUE of the
compound?
A.
B.
C.
D.
The compound is an allosteric activator.
The compound is an allosteric inhibitor.
The compound is an inhibitor that binds to the active site of the enzyme.
The compound is a catalyst for the reaction.
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