Download Answer Key 2016 Spring Biology (General) Exam #2

Biology 1 Exam #2
________________________________________________
Student Name
Lab Session
Welcome to the second exam, worth 100 points. Please read and follow all directions carefully.
You may have only your exam, scantron, and writing utensil on your desk during the exam. You
cannot possess or use any other materials nor may you communicate via any means with anyone
else during the exam. The use/possession of any other materials or communication with anyone
other than the instructor will be considered cheating and will result in failing the exam.
Good luck!
I. Multiple choice and matching. Choose the one correct answer for each of questions 1
through 23 and fill in your choice on your scantron sheet. (2 points each)
1) Energy is stored long-term in the bonds of _____ and used short-term to perform work from
a(n) _____ molecule.
A) ATP : glucose
B) an anabolic molecule : catabolic molecule
C) glucose : ATP
D) a catabolic molecule : anabolic molecule
2) The first law of thermodynamics states that:
A) energy is required to bring molecules into a cell against a concentration gradient
B) energy conversions are never 100% efficient…some energy is always “lost” as heat.
C) energy can neither be created nor destroyed
D) all living organisms must eat to derive energy
3) The second law of thermodynamics states that:
A) energy conversions are never 100% efficient…some energy is always “lost” as
heat.
B) energy is required to bring molecules into a cell against a concentration gradient
C) all living organisms must eat to derive energy
D) energy can neither be created nor destroyed
4) Which of the following is NOT true about enzymes?
A) They are consumed by the reactions they catalyze.
B) They are usually made of amino acids.
C) They lower the activation energy of chemical reactions.
D) Each one is specific to the particular substrate(s) to which it binds.
5) Which choice below is the correct chemical equation for cellular respiration?
A) 𝑪𝟔 𝑯𝟏𝟐 𝑶𝟔 + 𝟔𝑶𝟐 → 𝟔𝑪𝑶𝟐 + 𝟔𝑯𝟐 𝑶
B) 6𝐶𝑂2 + 6𝐻2 𝑂 → 𝐶6 𝐻12 𝑂6 + 6𝑂2
6) Which choice below is the correct chemical equation for photosynthesis?
A) 𝐶6 𝐻12 𝑂6 + 6𝑂2 → 6𝐶𝑂2 + 6𝐻2 𝑂
B) 𝟔𝑪𝑶𝟐 + 𝟔𝑯𝟐 𝑶 → 𝑪𝟔 𝑯𝟏𝟐 𝑶𝟔 + 𝟔𝑶𝟐
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7) Which of the following is the correct order of the three main stages of aerobic cellular
respiration?
A) glycolysis, citric acid cycle, electron transport chain
B) electron transport chain citric acid cycle glycolysis,
C) citric acid cycle, glycolysis, electron transport chain
D) electron transport chain glycolysis, citric acid cycle
8) The glucose that enters the glycolysis pathway is split into two molecules of _________.
A) ATP
B) phosphate
C) NADH
D) pyruvate
9) During the electron transport chain in cellular respiration, ATP is produced when
___________________________________.
A) electrons move down a concentration gradient
B) hydrogen atoms move against a concentration gradient
C) hydrogen ions move down a concentration gradient.
D) glucose moves against a concentration gradient
10) What is the final electron acceptor at the end of cellular respiration?
A) ATP
B) oxygen
C) carbon dioxide
D) glucose
11) What are the products of lactic acid fermentation?
A) ethanol and carbon dioxide
B) lactic acid and 𝐍𝐀𝐃+
C) acytaldehyde and NAD+
D) acytaldehyde and pyruvic acid
12) Fermentation happens in the absence of ____________.
A) oxygen
B) water
C) carbon dioxide
D) sodium
13) The electron carrier NAD+ picks up electrons during glycolysis and carries them to which
stage of cellular respiration?
A) Calvin cycle
B) electron transport chain
C) citric acid cycle
D) fermentation
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14) Where does the electron transport chain in cellular respiration occur in Eukaryotes.
A) chloroplast
B) ribosome
C) cell membrane
D) mitochondria
15)What is the energy of a photon first used to do in photosynthesis?
A) split a water molecule
B) energize an electron
C) produce ATP
D) synthesize glucose
16) Plants produce oxygen when they photosynthesize. Where does the oxygen come from?
A) splitting water molecules
B) ATP synthesis
C) the electron transport chain
D) chlorophyll
17) Which color(s) of light does chlorophyll a (the chlorophyll in most plants) absorb?
A) red and blue
B) green
C) green and blue
D) blue
18)Where in plant cells does the Calvin cycle take place?
A) thylakoid membrane
B) thylakoid space
C) stroma
D) granum
19)Which statement correctly describes carbon fixation?
A) the conversion of CO2 to an organic compound
B) the reduction of a high energy electron carrier to a low energy carrier
C) the production of carbohydrate molecules from the 3-carbon compound G3P
D) the use of ATP and NADPH to reduce CO2
20) What is the function of nucleic acids?
A) They carry the information for the functioning of the cell.
B) They provide structure for the cell.
C) They store energy for the cell.
D) They are catalysts in biochemical reactions.
21) DNA replicates by which of the following models?
A) conservative
B) semiconservative
C) dispersive
D) none of the above
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22) What are the parts of a DNA nucleotide?
A) a deoxyribose (5-carbon sugar), a phosphate group, and a nitrogenous base
B) a ribose (5-carbon sugar), a phosphate group, and a nitrogenous base
C) an amino group, a carboxyl group, a hydrogen atom, and an R group
D) glycerol and fatty acids
23) The DNA molecule is composed of 2 single strands of nucleotide chains twisted around each
other into a double helix. These chains are held together with what type of bonds?
A) hydrogen bonds
B) covalent bonds
C) ionic bonds
D) London forces
24) If a species of gopher has 21% THYMINE bases found in its DNA, what percent of its bases
will be GUANINE?
A) 21%
B) 42%
C) 58%
D) 29%
25) Amanatin is a toxin found in the death cap mushroom, Amanita phalloides. It inhibits RNA
polymerase, thus blocking
A) nuclear division
B) replication
C) protein synthesis
D) cellular respiration
26) The sequences of mRNA that are removed from an mRNA molecule in eukaryotic cells
before translation are
A) introns
B) exons
C) codons
D) amino acids
27) Which study did NOT help in determining the structure of DNA?
A) Roseland Franklin’s study using x-ray crystallography to photograph DNA.
B) Chargaff’s study that determined the ratios of nucleotides in DNA.
C) Meselson and Stahl’s study that determined how DNA is replicated.
D) Hershey and Chase’s study that showed that a virus injects DNA into a cell and not
proteins.
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Matching .
28) RuBisCo (ribulose-1,5-bisphosphate carboxylase)
B)
29) helicase E)
30) RNA polymerase A)
31) ATP synthase
D)
32) DNA polymerase C)
A) Enzyme that joins nucleotides complementary to a DNA template during RNA
synthesis
B) Enzyme that fixes the carbon from carbon dioxide to an organic molecule
C) Enzyme that proofreads every added new base to the new DNA strand during DNA
synthesis
D) Enzyme that facilitates the diffusion of hydrogen ions across the inner membrane of
mitochondria and chloroplasts.
E) Enzyme that unwinds and opens up the DNA helix.
II Definition. Please define each term in one or two sentence. Drawings would also help.
(3 points each)
1. semiconservative replication
the method used to replicate DNA in which the double-stranded molecule is separated and
each strand acts as a template for a new strand to be synthesized, so the resulting DNA
molecules are composed of one new strand of nucleotides and one old strand of nucleotides
2. metabolism
all the chemical reactions that take place inside cells, including those that use energy
and those that release energy
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III. Short Answer. (15 points)
A. What was the role of the sugars in the fermentation experiment?
Yeast catabolizes sugar to produce energy in the form of ATP.
B. What was the role of the yeast in the fermentation experiment?
Yeast is a fungus. This organism was used to determine the rate of fermentation.
C. What was the role of the water in the fermentation experiment?
The water activated the yeast. Water was also the solvent. The sugar was dissolved in
water. This helped the yeast to transport the sugar across its cell membrane.
D. What product did we capture in the balloons in the fermentation experiment?
carbon dioxide
E. What was the purpose of the control in this experiment?
A control group in an experiment is used as a comparison against the experimental group
to recognize any changes in the experimental group due to the variable measured and not
due to other standardized variables.
A control will improve confidence in your results. If the control behaved the way it was
expected, you can have confidence that the experimental group also behaved the way it
should have. If there was no carbon dioxide produced from the yeast given glucose and
kept at 37° C, there was probably something wrong with the yeast. Therefore, we would
have no confidence in the whole experiment.
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3’
DNA:
G T
A
C C G
G
A
T
A T C
5’
(15 points)
1. Using this strand of DNA as a template, DRAW A PICTURE of the complete DNA
molecule. You do not need to draw your molecule with atomic accuracy, but you do need to
draw both strands.
3’
G T
A
C
C
G
G A T
A T C
5’
5’
C
A T
G
G
C
C
T
3’
T
A
A G
2. Now draw a complete picture of the mRNA strand that will be made from this DNA.
Label the 5’ and 3’ ends of your mRNA strand. (Use the given DNA strand at the top of
this page as your template.)
5’
C
A U
G
G
C
C
U A
U
A G
3’
3. Carefully indicate the codons present in the mRNA strand from question 2.
C
A U
G
G C
C
U A
U
A G
4. Draw a COMPLETE picture of all the tRNA molecules that will match up with the
codons from the previous question. Include ALL APPROPRIATE amino acids and
anticodons in your picture.
his
5’
gly
leu
GUA CCG GAU AUC
tRNA
CAU GGC CUA UAG 3’
mRNA
5. Draw a picture of the completed protein coded for by this strand of DNA (abbreviations are
fine).
Show the amino acids in the same order they would be observed in the finished protein with
bonds.
his-gly-leu
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