Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #1
I. Multiple Choice. Fill in the best answer on the answer sheet.
1. Which enzyme would be most likely to be located in a peroxisome?
a. RNase
b. amino acid oxidase
c. b and d
d. catalase
e. acid phosphatase
2. In which organelle would most secretory proteins receive their first glycosylation?
a. RER
b. secretory vesicles
c. Golgi apparatus
d. SER
e. a and d
3. Dolichol phosphate ____________.
a. is a phosphatidyl protein
b. donates a block of carbohydrates to proteins destined for the cell membrane as they project through the
RER membrane
c. is a membrane phospholipid
d. and its attached carbohydrates flip from the membrane leaflet facing the RER lumen to the cytoplasmic
leaflet
e. b and c
4. Which enzyme would be most likely to be found in a lysosome?
a. b and d
b. acid phosphatase c. catalase
d. hexosaminidase
5. Which organelle is observable only in an animal cell?
a. mitochondria
b. vacuole
c. glyoxysome
d. peroxisome
e. amino acid oxidase
e. none of the above
6. Which of the following sequences is most likely to be part of a signal peptide of a secretory protein.
Refer to the diagram of amino acid R groups on the last page of the multiple choice section for help.
a. — gly - asp - met - glu - asp - gly - lys - arg - met —
b. — cys - arg - glu - lys - lys - arg - gly - met - asp —
c. — arg - leu - asp - lys - phe - glu - arg - pro - leu —
d. — lys - ala - met - gly - phe - gly - leu - pro - met
e. — leu - arg - lys - asp - glu - met - gly - asp - arg
7. What molecule carries 2 carbons at one point during aerobic respiration?
a. b and d b. citric acid
c. acetyl CoA
d. succinyl CoA
e. NADre
8. What molecule binds to electrons that drop off of the end of the mitochondrial electron transport chain
forming another common compound?
a. NADPre
b. O2
c. NADre
d. H2O
e. CO2
9. Which of the following occurs when ATP is produced from the joining of an ADP and a phosphate group?
a. Energy is released.
c. b and d
e. an hydrolysis reaction
b. Water is released.
d. a condensation-dehydration reaction
10. Which event(s) occur(s) during the glucose mobilization (pump priming) stage of glycolysis?
a. d and e
b. Two molecules of acetyl CoA transfer electrons to a 4-carbon molecule
c. Two molecules of ATP are used up.
d. A 6-carbon sugar is produced with 2 phosphate groups attached to one end
e. Glucose is changed into a compound that is readily cleaved into three 2-carbon phosphorylated units.
11. What enzyme is responsible for carbon fixation from the atmosphere in C4 plants?
a. Rubisco
b. acid phosphatase c. PEP carboxylase
d. ATP synthase
e. catalase
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #2
12. Which statement about glycolysis is true?
a. It uses molecular oxygen.
d. b and e
b. It occurs in plant cell cytoplasm
e. Glycolysis results in the gross production of 4 ATPs
c. Every living creature on Earth and viruses can carry out glycolysis.
13. What would happen in a cell if the electron transport chain were blocked?
a. NADre levels would decrease.
c. There would be a net decrease in oxygen.
b. NADox levels would increase.
d. FADre levels would increase.
e. a, b and d
14. Integrins bind to a specific three amino acid sequence (designated RGD) in a number of proteins. A
dish is coated with a protein containing the RGD sequence. Some cultured cells with integrins
embedded in their membranes were added to the culture dish along with tripeptides with the RGD
sequence. The cells do not bind to the dish. This is an example of _________.
a. allosteric inhibition
c. a and b
e. receptor degradation
b. noncompetitive inhibition
d. competitive inhibition
15. Which of the following is true of ribulose bisphosphate carboxylase?
a. It is often known as Rubisco. c. It is likely the most common enzyme on Earth.
b. It is often known as Ribisco. d. It converts CO2 from a gas to a solid.
e. a, c and d
16. What part of the cell cycle is responsible for gearing up the cell for cell division?
a. S
b. interphase
c. M
d. G1
e. G2
17. What is the name of a cell junction that contains actin filaments; this cell junction helps to hold cells
together at their apical surfaces and when their actin filaments contract in a coordinated fashion, they
can cause a flat epithelium to fold, as happens when the nervous system forms in developing
vertebrate organisms?
a. c and d
b. zonula occludens
c. maculae adherens
d. spot desmosomes
e. belt desmosome
18. What anatomical specialization is essential for C4 photosynthesis?
a. Mesophyll cells arranged around vascular tissue are surrounded by bundle sheath cells.
b. Two cylinders of cells surround the plant's vascular tissues: bundle sheath cells on the inside and
mesophyll cells on the outside.
c. Kranz anatomy
d. b and c
e. larger and permanently open stomata
19. What is the importance of regulating the conversion of NAD to NADP in the cell?
a. High amounts of NAD mean that the cell will shrink.
b. High amounts of NAD will lead to the cell running primarily biosynthetic reactions.
c. High amounts of NADP lead to the activation of catabolic reactions that produce ATP.
d. Low amounts of NAD lead to the activation of anabolic reactions that generate large molecules
like polysaccharides and the monomers of which they are constructed.
e. b, c and d
20. Which of the following molecules has been reduced by binding to high-energy electrons?
a. ATP
b. FADre
c. FADox
d. NADre
e. b and d
21. You are studying some photosynthetic bacteria found in the sulfur pools of Yellowstone Park. They
contain only one photosystem and yet seem to be able to carry out both cyclic and non-cyclic
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #3
photophosphorylation. The sulfur in the pools is found in various forms including hydrogen sulfide
(H2S), an electron-rich compound. How could the bacteria carry on photosynthesis with just one
photosystem?
a. none of the other answers
b. They acquire electrons from water to replace those stored in NADPox.
c. They acquire electrons from water to replace those stored in NADre.
d. They acquire electrons from hydrogen sulfide to replace those stored in NADPox.
e. They make ATP whether they are carrying on respiration or non-cyclic photophosphorylation.
22. According to chemiosmosis, the energy stored in ATP by mitochondrial electron transport is
generated when __________.
a. ATP synthetase produces NADPre in addition to ATP
b. electron transport drives a transmembrane H+ ion pump that establishes a steep H+ ion gradient
c. electrons are transported hyperkinetically
d. energy is stored in an electrochemical gradient between the thylakoid disk lumen and the stroma
e. b and d
23. The importance of the Krebs (citric acid) Cycle in cell metabolism is that it ___________.
a. makes important biochemical intermediates
c. makes NADox
e. a, b and d
b. makes FADre
d. makes ATP
24. You are conducting an experiment in photosynthesis. You have radioactively labeled the oxygen in
a compound and have observed that this oxygen is soon seen in the carbohydrates of the plant. What
compound was labeled?
a. water b. carbon monoxide
c. starch
d. carbon dioxide
e. glucose
25. In what part of the cell can lysosomes form?
a. b, c and d
c. GERL
b. smooth vesicles
d. in the Golgi apparatus
e. c and d
26. Radiolabeled monosaccharides are given to growing secretory cells. Over which of the following
structures would silver grains first appear?
a. rough ER
b. Golgi apparatus
c. secretory vesicles
d. a and e
e. smooth ER
27. Patients with I-cell disease __________
a. may make excess receptors for mannose-6-phosphate in carbohydrates attached to lysosomal enzymes
b. may be unable to add phosphate groups to mannose residues in the carbohydrates of lysosomal enzymes
c. synthesize peroxisomal enzymes without properly marking them as such
d. are unable to place lysosomal enzymes effectively within lysosomes
e. b and d
28. What characteristics of the signal peptide allow it to penetrate the RER membrane easily?
a. It is 15 - 30 amino acids long.
d. It is mostly made up of hydrophilic amino acids.
b. Its sequence is recognized by the GERL.
e. c and d
c. Its central 9 - 12 amino acids are primarily hydrophobic.
29. Which of the following is a function of the rough endoplasmic reticulum?
a. It adds sugars to carbohydrate chains on presumptive membrane proteins.
b. It can excise amino acid segments from proteins.
d. It synthesizes secretory proteins.
e. a and d
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #4
Cell Biology
December 16, 2010
Name _________________________________
c. It synthesizes domestic proteins.
30. What is the name given to carbohydrates bound to serine or threonine residues on a secretory protein?
a. N-linked carbohydrates b. O-linked carbohydrates c. proteoglycans d. glycoproteins e. a and b
31. What may account for differences in the appearance of RER and SER?
a. the presence of ribosomes on the RER
d. the distribution of ribosome docking proteins (translocons)
b. the relative amounts of certain enzymes
e. a, b and d
c. the relative amounts of certain nucleic acids
32. What is the name of the process that is responsible for destroying the organelles of reticulocytes, the
cells that mature into red blood cells?
a. autophagy
b. autolysis
c. apoptosis
d. extracellular digestion
e. b and c
33. Which of the following activities is triggered by the release of calcium ions?
a. secretion b. exocytosis c. muscle contraction d. activation of a fertilized egg e. all of the above
34. What process is responsible for the restructuring of bone during an organism’s life and the
destruction of potential cancer cells when their abnormalities are detected?
a. autophagy
b. autolysis
c. apoptosis
d. extracellular digestion
e. b and c
35. Strauss performed an experiment in 1964. He injected the enzyme horseradish peroxidase into his
experimental organism. Some cells in the organism took up the horseradish peroxidase by endocytosis.
Eventually, the endosomes containing horseradish peroxidase met up with lysosomes and merged with
them. What color were the vesicles containing the horseradish peroxidase after they were presented with
special substrates for the enzyme that serve as a marker for lysosomes and for horseradish peroxidase
and before they fused with a lysosome?
a. yellow
b. blue
c. red
d. green
e. purple
36. The mRNA for a well-known secretory protein is isolated and placed in a test tube in the presence of
all the substances required for in vitro protein synthesis. The sequence of the protein produced in
vitro is then compared to the sequence of the purified secretory protein from the cell. The amino acid
sequences of the two proteins are not the same. What is the explanation?
a. A short chain of mostly hydrophobic amino acids was removed from the C-terminal end of the
polypeptide in the test tube before it was analyzed.
b. A short chain of mostly hydrophilic amino acids was chopped off the N-terminal end of the protein
purified from the secretory cell.
c. The mRNA was cleaved after being translated in the test tube,
d. A largely hydrophobic segment at the N-terminal end of the polypeptide is cut off of a protein
synthesized in vitro (in the test tube) and degraded by the signal peptidase.
e. none of the above
37. Fermentation permits continuous glycolysis in plants because ___________.
a. it serves to recycle NADre, which is needed for glycolysis d. lactic acid is produced, recycling NADox
b. it serves to recycle NADox, which is needed for glycolysis e. b and d
c. there is a net increase in the production of NADPox
38. Some of the molecules of the electron transport chain in chloroplasts accept electrons while others
accept electrons and hydrogen ions. This is significant because __________.
a. it explains how these molecules can transport protons for the purpose of setting up a proton gradient
b. it explains how the energy that helps to make ATP in the chloroplasts is generated
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #5
c. a and b
d. it explains how electrons are added to NADPre
e. it explains why Ralph Nader is such a jerk. (Come to think of it - nothing explains that)
39. Which statement below about noncyclic photophosphorylation is true?
a. ATP is produced from the electron derived from the Photosystem II reaction center.
b. O2 is produced when H2O is split
c. a and b
d. The electron from the Photosystem I reaction center ends up back in Photosystem I.
e. Electrons from Photosystem I drive the production of ATP.
40. Given that glycolysis, Krebs cycle and electron transport are regulated by allosteric enzymes that
control the reactions, what do you think happens to phosphofructokinase, one of the first enzymes in
the glycolytic pathway, when ATP levels are very low?
a. ATP is not found at the enzyme’s allosteric site and it works more quickly.
d. Pyruvate production rises.
b. It is inhibited and begins to work more slowly.
e. a and d
c. It denatures.
41. The lollipop structures are ___________.
a. b, c and d
c. ATPase molecules
b. found on thylakoid membranes
d. found on the cristae membrane
e. b and d
42. What is the net gain in ATPs when 32 molecules of glucose are processed aerobically in a cell with
high energy requirements?
a. 1156
b. 32
c. 1216
d. 36
e. 38
43. How many carbons from 45 original glucose molecules enter the Krebs cycle when a cell operates
aerobically?
a. 180
b. 270
c. 4
d. 6
e. none
44. How many ATPs are made from 72 original glucose molecules when a cell is involved in fermentation?
a. 144
b. 1368
c. none
d. 1296
e. 72
45. An animal cell is injected with a low molecular weight fluorescent molecule called fluorescein.
After a short period of time, adjacent cells are seen to be fluorescing just like the originally injected
cell. The explanation is that the cells ________.
a. are connected by plasmodesmata
d. were damaged by the injection procedure
b. are connected by gap junctions
e. are connected by hemidesmosomes
c. are joined by gap junctions & plasmodesmata
46. Which metabolic pathway probably evolved first?
a. Krebs cycle
c. cyclic photophosphorylation
b. noncyclic photophosphorylation d. glycolysis
e. fermentation
47. What is the name of the cytoskeletal element associated with maculae adherens?
a. keratin
b. microfilaments
c. tubulin
d. a and e e. tonofilaments
48. How would one determine the time it takes for the proteins destined for secretion to be synthesized,
processed and finally secreted and the pathway the protein follows at the same time?
a. c and d
c. pulse-chase experiment
e. b, c and d
b. labeling with radioactive sugars
d. autoradiography
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #6
49. What controls the sequence of carbohydrates on oligosaccharides attached to secretory proteins?
a. whatever carbohydrates are close to the proteins
b. the sequence of galactose oxidases in the RER and SER
c. the arrangement and sequence of glycosyltransferases in the RER, SER and Golgi apparatus
d. the sequence of nucleotides in the nucleotide sugars
e. b and c
50. ________ attach cells to _________.
a. Hemidesmosomes, a noncellular surface c. Maculae adherens, neighboring cells
e. a, b and c
b. Zonulae adherens, neighboring cells
d. Zonulae adherens, a noncellular surface
51. Storage diseases like Hurler's syndrome and Tay-Sachs disease may result from ______ enzymes.
a. nonfunctional peroxisomal
c. nonfunctional lysosomal
e. c and d
b. missing mitochondrial
d. overabundant lysosomal
52. Which name below would be the name of an enzyme in the RER, SER or Golgi apparatus that is responsible
for adding sugars to growing oligosaccharide chains attached to the proteins passing through them?
a. glucosyltransferase
c. peptidylsynthase
e. glycosylsynthetase
b. a and d
d. glycosyltransferase
53. A scientist isolates two specific mRNAs. One codes for the enzyme tigerase, a really good golfer
enzyme that strays; the other codes for the enzyme beckase, a blowhard enzyme that fake cries on TV and
knows a lot less than it thinks. Both mRNAs are placed in a test tube with RER vesicles stripped of their
ribosomes, free ribosomes and precursors for protein synthesis. When the protein synthesis reaction is
complete, beckase is found in the liquid portion of the test tube outside the vesicles; tigerase is found
inside the vesicles. What can one conclude about the two proteins?
a. Beckase is a secretory protein; tigerase is a domestic protein.
b. Beckase is a domestic protein; tigerase is a secretory protein.
c. Both proteins are secretory.
d. Both proteins are meant for domestic use.
e. Tigerase diffuses into the vesicle after synthesis; beckase is an intrinsic membrane protein.
54. In order for a protein to end up in the cell membrane, which of the following things would it need to
have as part of its initial primary structure?
a. a signal peptide b. a signal peptidase c. a sequence that opens the translocon d. a 5'-end e. a and c
55. Which of the cell adhesion molecules below always requires the presence of calcium?
a. integrins b. sponge cell aggregation factors
c. cadherins
d. b and c
e. IGSFs
56. Which of the following can be found attached to the outer leaflet of the RER?
a. signal peptidase b. dolichol phosphate
c. ribosomes
d. an RNA enzyme
e. b, c and d
57. You mix secretory and domestic protein mRNA, ribosomes, naked RER vesicles that have been
stripped of their ribosomes and everything else you need to synthesize proteins in a test tube and let
them incubate for 30 minutes. After the incubation, what do you find in the test tube?
a. domestic proteins floating free in the buffer in the test tube
b. secretory proteins inside RER vesicles with ribosomes bound to their inner surface
c. secretory proteins inside RER vesicles with ribosomes bound to their outer surface
d. domestic proteins in the RER vesicles with ribosomes bound to their inner surface
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #7
e. a and c
Cell Biology
December 16, 2010
Name _________________________________
58. Which cell junction below may attach epithelial cells to each other and are built to withstand a great
deal of force in holding cells together?
a. zonulae occludens
b. maculae adherens
c. zonulae adherens d. belt desmosomes
e. b, c and d
59. What changes can be made in a secretory protein after it has already entered the RER?
a. addition of new amino acids to the signal sequence
d. b and c
b. addition of a segment of the amino acids to the interior of the secretory protein
e. a, b and c
c. addition of sugars to the carbohydrates donated to the protein by dolichol phosphate
60. Which organelle is most prominent in the photosynthetic tissues of plants?
a. peroxisomes b. lysosomes
c. glyoxysomes
d. contractile ring
e. centrioles
61. Which cell adhesion molecules that bind to specific carbohydrates on the cell surface are named
after a group of plant molecules that are known for their ability to bind specific carbohydrates?
a. selectins b. lectins
c. IgSFs
d. integrins
e. cadherins
62. What cell junction(s) is (are) responsible for preventing materials from getting past an epithelium like the
urinary bladder epithelium? It does so by preventing these materials from moving between epithelial cells.
a. gap junctions
b. gapulae adherens c. maculae adherens d. tight junctions e. c and d
63. A pulse-chase experiment is carried out by exposing rat parotid cells to radioactive glycerol for a
brief period of time followed by increasing chase periods in the presence of unlabeled glycerol
precursors? What is the most important revelation of this technique?
a. the time it takes to synthesize a single membrane lipid
b. the pathway membrane lipids follow through the cell on their way to the membrane
c. the time it takes for a secretory protein to be secreted
d. the pathway membrane proteins follow through the cell on their way to the membrane
e. c and d
64. You mix radiolabeled mouse liver cells with a number of different cell types, each grown to cover
separate Petri dishes. The radiolabeled cells are most likely to adhere to which cell type below?
a. mouse liver
b. rat liver
c. a and e
d. a and b
e. mouse retina
65. You isolate the gene for a secretory protein and remove the nucleotides that code for the first 30
amino acids on the protein's N-terminal end. You are then able to add this nucleotide sequence to the
beginning of the gene for a domestic protein. You are able to replace the normal gene for this domestic
protein in a rat cell with the altered form of the gene you have produced. When the rat cell and its
descendents start to make this protein where can it be found?
a. in the RER lumen
c. in the Golgi complex
e. a and c
b. in the peroxisomes
d. in the cytoplasm
66. __________ allow molecules with low molecular weights to pass between cells via a direct
connection between their cytoplasms. The purpose of this connection is to allow communication
between the cells so that they can _________.
a. Plasmodesmata, act in concert
c. Gap junctions, swell
e. a and d
b. Plasmodesmata, disaggregate
d. Gap junctions, communicate with each other
67. A red sponge is dissociated mechanically and a yellow sponge is dissociated chemically by placing
it in Ca+2 - Mg+2 - free sea-water. Both cell suspensions are washed in natural sea-water a number of
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #8
times and placed together in natural sea-water at 4°C. Washes were performed by centrifuging the
dissociated sponge cells and removing the supernatant. If the supernatant from the first centrifugation
(i. e., the solution surrounding the cells during dissociation) of the yellow sponge is added to the
above mixture of red and yellow sponges, what happens?
a. Neither sponge reassociates.
d. Both sponges reassociate into one mass
b. The red sponge reassociates; the yellow sponge does not. e. Both sponges reassociate into separate masses.
c. The yellow sponge reassociates; the red sponge does not
68. What happens if the mixture of dissociated red and yellow sponges mentioned above is cultured at
4°C with the addition of supernatant from the initial centrifugation of the red sponge?
a. Both sponges eventually reassociate into one mass. d. The red sponge reassociates; the yellow does not.
b. Neither sponge reassociates.
e. Both sponges eventually reassociate independently.
c. The yellow sponge reassociates; the red does not.
69. Three tissues (A, B and C) from a vertebrate embryo are dissociated and then allowed to reassociate
in pairs. If in these aggregates, Tissue B ends up internal to Tissue C and Tissue B ends up external
to Tissue A, then:
a. Tissue C will be external to Tissue A c. Tissue A will be external to Tissue C
e. a and b
b. Tissue A will be internal to Tissue C. d. Tissue A will be internal to Tissue D.
70. What kind of disease would be likely to be caused by a defect in hemidesmosomes?
a. a disease in which cells die indiscriminately
b. a disease in which blisters form in the skin
c. a disease in which gashes form between skin cells
d. a disease in which cancerous lesions form frequently
e. a disease in which dark patches form in the skin
71. A disease in which an epithelial layer designed to contain liquid secretions leaks somewhat causing
inflammation in its vicinity is most likely to indicate defects in which cellular structures?
a. mitochondria b. hemidesmosomes c. zonula occludens d. spot junctions e. plasmodesmata
72. What organelle is responsible for converting lipids directly to carbohydrates?
a. lysosome b. glyoxysome c. chloroplast
d. peroxisome
e. mesosome
73. In which cell junction do the membranes have the same distance separating them as in regions of the
membrane where there are no cell junctions?
a. spot desmosomes b. maculae adherens
c. tight junctions
d. gap junctions
e. a and b
74. Which of the following happens after the SRP leaves the ribosome bound to the RER?
a. Protein synthesis begins again.
d. The protein being synthesized enters the cytoplasm.
b. Protein synthesis is temporarily suspended.
e. a and c
c. The protein being synthesized enters the RER lumen.
75. Starting with the apical surface of cells that secrete proteins into a duct at that surface, in what order
would you encounter cell junctions if you could travel between the cells from the apical surface toward
the basal surface of the cells?
a. belt desmosome, tight junction, spot desmosome d. tight junction, belt desmosome, spot desmosome
b. tight junction, spot desmosome, belt desmosome
e. spot desmosome, gap junction, belt desmosome
c. spot desmosomes, belt desmosomes, tight junctions
76. Which cell junction would prevent proteins embedded in the cell membrane and located on the
lateral or basal surface of the cell from moving to the apical surface of those same cells?
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #9
a. zonula adherens
Cell Biology
December 16, 2010
Name _________________________________
b. belt desmosomes
c. b and d
d. tight junctions
e. a and d
77. A(n) _______ located in the _______ is a modified lysosome.
a. acrosome, unfertilized egg
c. acrasin, peroxisome e. acrosome, head of a sperm
b. mesosome, head of the sperm
d. acrasin, lysosome
78. The first sugars added to dolichol phosphate are added in what location?
a. in the RER lumen b. in the SER lumen c. in the Golgi d. in the cytoplasm
e. on the ribosome
79. Which of the molecules below is an example of the type of molecule that glycosyltransferases
require to complete their reaction of adding sugars to growing oligosaccharide chains?
a. nucleotide sugars b. CMP-sialic acid
c. ATP
d. NADre
e. a and b
80. Which of the following proteins would be likely to be synthesized on free cytoplasmic ribosomes?
a. integrins b. glycolytic enzymes c. steroid receptors d. b and c e. insulin receptors
H
CH2 CH2 CH2 N
arginine
C
NH2
NH
CH
CH
3
CH
2
leucine
CH
CH2
O
CH
2
C
HO
CH2
OH
aspartate
tyrosine
CH3
CH
valine CH
CH SH
2
cysteine
3
CH3
methionine
O
CH
2
CH
2
glutamine
NH2
CH OH
2
serine
C
OH
O
CH2 CH2 CH2 CH2 NH2
lysine
H
H
C
C
CH2 CH2
glutamate
CH2 CH2 S CH3
alanine
H
glycine
phenylalanine
O
3
CH3
OH threonine
CH
2
CH
NH2
asparagine
C CH 2 CH3
CH3 isoleucine
CH
C
2
CH
2
histidine
NH+
HN
C
H
2
CH2 HC
N proline
H
CH
C
CH2
tryptophan
C
HC
N
H
III. Lecture Short Answer
1. What lysosomally controlled cell process is exemplified by:
a. digestion of the membranes around an egg by a sperm cell
b. digestion of a bacterium phagocytosed by an amoeba
c. the resorption of the tadpole’s tail
d. the breakdown of cellular organelles to buy time in the face of starvation
(4 points)
2. You have fractionated a plant cell into a cytoplasmic portion, a nuclear portion, a fraction composed
of the inner mitochondrial membranes, a fraction composed of the outer mitochondrial membranes, a
fraction composed of thylakoid membranes, a fraction containing the chloroplast stroma and a
fraction containing the mitochondrial matrix. Where would you expect to find the
a. the enzymes responsible for glycolysis?
b. ATP synthase?
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #10
c. respiratory electron transport chain?
Cell Biology
December 16, 2010
Name _________________________________
d. photosystem II?
e. Krebs cycle?
f. Calvin-Benson cycle enzymes?
(6 points)
3. What does SRP stand for? What are the two major components of the SRP? (3 points)
4. What pathway do secretory proteins follow on their way to the cell surface, starting with their
synthesis? (3 points)
5. Where are peroxisomes assembled? (1 point)
6. What is the name of the process that generates most of the energy that is used to produce ATP in the
mitochondrion? What kind of gradient does it produce? (2 points)
7. What is wrong with the following list of molecules? (1 point)
UDP-glucose, UDP-galactose, CMP-sialic acid, CMP-glucuronic acid, UDP-sialic acid
BONUS QUESTIONS
1. Describe the flow of electrons during noncyclic photophosphorylation from the place where they
originate to where they eventually end up? What drives their movement? (3 points)
2. The following statements apply to photosynthesis, cellular respiration, both processes or neither
process. Indicate which process is referred to in each statement by writing either P, C, PC or N in the
blank before each statement. (14 points)
_______ a. Produces oxygen as a product
_______ b. ATP is used up at some point in the process
_______ c. Part of the process occurs in the chloroplast
_______ d. Generates phosphorylated lipids
_______ e. Involves the splitting of a water molecule
_______ f. Reduced coenzymes and other electron-carrying molecules are oxidized during the process
Biology 362
Cell Biology
Dr. Joel B. Piperberg
December 16, 2010
Final Exam
Name _________________________________
Page #11
_______ g. Carbon dioxide is a reactant in this process
_______ h. During this process, a six-carbon molecule is formed from a two-carbon fragment and a
four-carbon fragment
_______ i. Some of the reactions involved occur in a milieu called the stroma
_______ j. Uses chemiosmosis as the source of energy to make ATP
_______ k. UTP is produced during the process
_______ l. Produces NADPre at some point in the process.
_______ m. Water is produced during this process
_______ n. FADox is produced during the process
_______ o. This process occurs in both plants and animals
_______ p. Involves a cycle of reactions that binds CO2 to a molecular relative of ribose
3. What do plants produce when they operate anaerobically? (2 points)
4. When animal cells operate anaerobically, what do they generally produce? (1 point)
5. Cyclic photophosphorylation normally results in the production of ___________. (1 point)
6. Name a molecule that is a relative of ATP that participates in photosynthesis. (1 point)
7. What is another name for autolysis? (1 point)
8. You are working with a gene in yeast cells. After cloning and sequencing it, you discover that there is
a very similar gene in humans. If you take a normal version of the human gene and introduce it into a
yeast cell that possesses a mutant version of its corresponding gene, what is likely to happen? (1
point)
9. Who was the President at the start of the Great Depression? (1 point)
10. Name two actors who have portrayed Vito Corleone. (2 points)
11. What is crossing over and why is it advantageous? (2 points)
12. An organism has a diploid number of 36. How many total chromosomes are in 12 of its sperm cells?
(1 point)
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #12
Cell Biology
December 16, 2010
Name _________________________________
13. An organism has a haploid number of 48. How many total chromosomes are there in 14 kidney
cells from this organism? (1 point)
14. Which phase of mitosis or meiosis is defined by the following descriptions? Specify the phase and
whether you are talking about mitosis, meiosis I, or meiosis II. (6 points)
a. A haploid number of chromosomes is lined up in the center of the cell; each chromosome consists
of 2 chromatids.
b. A diploid number of chromosomes splits at the centromere and begins moving to the opposite poles
of the cell.
c. A haploid number of chromosomes decondenses and becomes sequestered in the newly formed
nuclei of 4 daughter cells; each chromosome consists of 1 chromatid.
d. A haploid number of chromosomes condenses and each can be seen to consist of two chromatids;
they are unpaired and the nuclear membrane begins to disintegrate.
e. A diploid number of unpaired chromosomes lines up in the center of the cell.
f. A haploid number of chromosomes separates into two daughter nuclei; each chromosome has 2
chromatids.
15. Who was the President who immediately preceded Abraham Lincoln? (1 point)
16. Which organelle is most prominent in the seedlings and heterotrophic, fat-storing tissues of plants? (1 points)
17. A disease in which the urinary bladder has slight leakage would be likely to have a defect in what
cellular structure? (1 point)
18. Why is the number of chromosomes cut in half during meiosis? (2 points)
19. What is the name of the process by which exact copies of DNA are made? (1 point)
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #13
Cell Biology
December 16, 2010
Name _________________________________
20. What is the name of the enzyme that makes a DNA copy of RNA? (1 point)
21. What was the name of the scientist who proposed the Central Dogma? (1 point)
22. What is the name of the process by which mRNA is converted into proteins? (1 point)
23. What is the job of the cell spindle? (1 point)
24. What is the name of the process triggered when Rubisco uses O2 as a substrate? (1 point)
25. What holds together sister chromatids? (1 point)
26. What is the name of the enzyme that forges the peptide bond and of what macromolecule is it
composed? (2 points)
27. At what site does the first charged tRNA enter the ribosome? (1 point)
28. What is the first amino acid laid down in most proteins and what codon codes for it? (2 points)
29. How many codons actually code for amino acids? (1 point)
30. An alien organism contains 6 different nucleotides in its DNA and 33 amino acids inserted into its
proteins. How many letters long are the codons for this organism likely to be if they obey the same
rules as the codons in organisms from Earth? (1 point)
Biology 362
Dr. Joel B. Piperberg
Final Exam
Page #14
Cell Biology
December 16, 2010
Name _________________________________
Merry Christmas, Happy Chanukah, Wonderful Kwanzaa and Happy New Year
after you finish the survey below but not before.
Course Survey (2 points)
1. The thing I liked most about this course was
2. The thing I liked least about this course was
3. If I could change one thing about this course, it would be
4. The lab I liked most was
5. The lab I liked least was
6. What topic that was not discussed would you most like to hear about?
7. General comments