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Cell Biology
1.
Which of the following contains nitrogen in addition to carbon, oxygen, and hydrogen?
A) an amino acid such as glycine
B) an alcohol such as ethanol
C) a monosaccharide such as starch
D) a steroid such as testosterone
E) a hydrocarbon such as benzene
2.
Which bonds are created during the formation of the primary structure of a protein?
A) peptide bonds
B) hydrogen bonds
C) disulfide bonds
D) Only A and C are correct.
E) A, B, and C are correct
3.
Which of the following is true of both starch and cellulose?
A) They can both be digested by humans.
B) They are both structural components of the plant cell wall.
C) They are geometric isomers of each other.
D) They are both polymers of glucose.
E) They are both used for energy storage in plants.
4.
Which of the following is true concerning saturated fatty acids?
A) They are the predominant fatty acid in corn oil.
B) They have double bonds between the carbon atoms of the fatty acids.
C) They are usually liquid at room temperature.
D) They are usually produced by plants.
E) They have a higher ratio of hydrogen to carbon than do unsaturated fatty acids.
5.
When biologists wish to study the internal ultrastructure of cells, they most likely would use
A) a transmission electronic microscope.
B) a light microscope.
C) a scanning electron microscope.
D) both A and C.
E) A, B, and C.
6.
Which of the following is not a part of the endomembrane system?
A) rough endoplasmic reticulum
B) smooth endoplasmic reticulum
C) Golgi apparatus
D) mitochondria
E) lysosomes
7.
Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?
A) lysosomes
B) mitochondria
C) contractile vacuoles
D) ribosomes
E) smooth endoplasmic reticulum
8.
All of the following are functions of integral membrane proteins except
A) enzyme synthesis.
B) active transport.
C) cell adhesion.
D) cytoskeleton attachment.
E) hormone reception.
9.
All of the following statements about membrane structure and function are true except:
A) Both sides of a membrane are identical in structure and function.
B) Special membrane proteins can cotransport two solutes by coupling diffusion with active
transport.
C) Diffusion, osmosis, and facilitated diffusion do not require any energy input from the cell.
D) Voltage across the membrane depends on an unequal distribution of ions across the plasma
membrane.
E) Diffusion of gases is faster in air than across membranes.
10. The presence of cholesterol in the plasma membranes of some animals
A) enables the animal to remove hydrogen atoms from saturated phospholipids.
B) makes the animal more susceptible to circulatory disorders.
C) makes the membrane less flexible, so it can sustain greater pressure from within the cell.
D) enables the membrane to stay fluid more easily when cell temperature drops.
E) enables the animal to add hydrogen atoms to unsaturated phospholipids.
11. According to the fluid mosaic model of cell membranes, which of the following is a true statement about
membrane phospholipids?
A) They have hydrophilic tails in the interior of the membrane.
B) They can move laterally along the plane of the membrane.
C) They frequently flip-flop from one side of the membrane to the other.
D) They are free to depart from the membrane and dissolve in the surrounding solution.
E) They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the
membrane.
12. Which kind of metabolic poison would most directly interfere with glycolysis?
A) an agent that reacts with oxygen and depletes its concentration in the cell
B) an agent that binds to pyruvate and inactivates it
C) an agent that inhibits the formation of acetyl coenzyme A
D) an agent that reacts with NADH and oxidizes it to NAD+
E) an agent that closely mimics the structure of glucose but is not metabolized
13. All of the following statements about glycolysis are true except:
A) Glycolysis makes ATP exclusively through substrate-level phosphorylation.
B) The enzymes of glycolysis are located in the cytosol of the cell.
C) Glycolysis has steps involving oxidation-reduction reactions.
D) Glycolysis can operate in the complete absence of O2.
E) The end products of glycolysis are CO2 and H2O.
14. What could happen to target cells in an animal that lack receptors for local regulators?
A) They would divide but could never reach full size.
B) They would not be expected to multiply in response to growth factors from nearby cells.
C) They could develop normally in response to neurotransmitters instead.
D) They could compensate by receiving nutrients via a factor.
E) Hormones would not be able to interact with target cells.
15. Which of the following is true of synaptic signaling and hormone signaling?
A) Both use neurotransmitters, but hormone signaling is for adjacent cells in animals only.
B) Hormone signaling is important between cells that are at greater distances apart than in synaptic
signaling.
C) Both are forms of paracrine signaling.
D) Hormone signaling occurs in animals only.
16. From the perspective of the cell receiving the message, the three stages of cell signaling are
A) the alpha, beta, and gamma stages.
B) signal reception, nucleus disintegration, and new cell generation.
C) signal reception, signal transduction, and cellular response.
D) the paracrine, local, and synaptic stages.
E) signal reception, cellular response, and cell division.
17. All of the following statements are true except:
A) Mitosis may occur without cytokinesis.
B) Mitosis produces new nuclei with exactly the same chromosomal endowment as the parent
nucleus.
C) Mitosis and cytokinesis are required for asexual reproduction.
D) All cells come from a preexisting cell.
E) The mitotic spindles in prokaryotic cells are composed of microtubules.
18. Cytokinesis usually, but not always, follows mitosis. If a cell completed mitosis but not cytokinesis, what
would be the result?
A) a cell with two nuclei but with half the amount of DNA
B) a cell with a single large nucleus
C) a cell with two nuclei
D) a cell with high concentrations of actin and myosin
E) a cell with two abnormally small nuclei
19. Which of the following is a true statement about viruses?
A) A single virus particle contains both DNA and RNA.
B) Viruses are classified below the cellular level of biological organization.
C) Even small virus particles are visible with light microscopes.
D) A and B only are true.
E) A, B, and C are true.
20. The host range of a virus is determined by
A) the structure of the viral capsid.
B) whether the virus nucleic acid is DNA or RNA.
C) proteins on the surface of the cell.
D) enzymes produced by the virus before it infects the cell.
E) both A and C.
21. Which of the following organelles has protein-phospholipid membranes, energy conversion enzymes, and
ribosomes similar to those found in bacteria?
A) Lysosome
B) Peroxisome
C) Rough Endoplasmic reticulum
D) Centriole
E) Mitochondrion
22. The complementary RNA sequence for GATCAA is
A)
B)
C)
D)
E)
CTAGTT
CUAGUU
AGCTGG
AGCUGG
TCGACC
23. In the presence of a fixed concentration of a competitive inhibiter, which of the following would best
characterize an enzyme-catalyzed reaction when the concentration of the substrate is increased?
A) The inhibition does not change.
B) The inhibition decreases.
C) The Km increases.
D) The maximal rate of reaction (Vmax) increases
E) The maximal rate of reaction (Vmax) decreases.
24. Plasmodesmata most closely resemble which of the following structures in animal cells?
A) Desmosomes
B) Gap junctions
C) Basal junctions
D) Tight junctions
E) Ion channels
25. All of the following cellular events involve actin filaments EXCEPT
A) amoeboid movement
B) cytoplasmic streaming
C) cytokinesis
D) contraction of smooth muscles
E) flagellar movement in bacteria
26. Eukaryotic and prokaryotic cells share all of the following features EXCEPT
A) ribosome-dependent protein synthesis
B) ATP synthesis linked to a proton gradient
C) a selectively permeable plasma membrane
D) a cytoskeleton of tubulin
E) a semiconservative replication of DNA
27. Mitochondria and chloroplasts carry out oxidative phosphorylation and photophosphorylation,
respectively, by means of
A) conformational coupling
B) chemiosmotic coupling
C) high-energy intermediate coupling
D) photorespiration
E) sliding filaments
28. Successful reproduction of a lytic virus requires that all of the following processes occur EXCEPT
A) incorporation of viral DNA into host cell DNA
B) translation of viral mRNA
C) binding of the virus to the host cell’s surface
D) penetration of the viral genome into the host cell
E) replication of the viral genome
29. C4 plants, by decreasing photorespiration and efficiently carrying out photosynthesis, can
A) decrease stomatal openings and thereby reduce water loss
B) decrease stomatal openings and thereby reduce leaf temperature
C) increase stomatal openings and thereby increase water loss
D) increase stomatal openings and thereby increase leaf temperature
E) increase stomatal openings and thereby increase transpiration rates
30. It has been proposed that mitochondria and chloroplasts evolved from certain bacteria that existed as
endosymbiotic organisms in early cells. Which of the following would best support this hypothesis?
A) Both organelles contain DNA molecules.
B) Both organelles have microtubules.
C) Both organelles lack mRNA
D) Mitochondria, but not chloroplasts, are surrounded by a double membrane.
E) Chloroplasts, but not mitochondria, are able to synthesize protein.
North Hollywood High Science Olympiad
Summer 2008
CELL BIOLOGY TEST
NAME:_______________________
SCORE:______________________
1. All of the following are chemoheterotrophs EXCEPT:
A)
Staphylococci aureus.
B)
fungi.
C)
algae.
D)
animals.
E)
non-photosynthetic roots.
2. Metabolon characteristics include all EXCEPT:
A)
“units of metabolism”.
B)
discrete multienzyme complex.
C)
soluble enzymes associated into stable
multienzyme complexes.
D)
membrane bound multienzyme systems.
E)
all are characteristics.
3. At the end of stage 1 of aerobic catabolism, glycolysis,
the carbons appear as
A)
pyruvate.
B)
CO2..
C)
acetyl group of acetyl-CoA.
D)
glucose.
E)
alanine.
4. What are the final products of aerobic catabolism?
A)
pyruvate and H2O.
B)
acetyl-CoA and CO2.
C)
CO2 and H2O.
D)
pyruvate and acetyl-CoA.
E)
ammonia and O2.
5. The dehydrogenase enzymes facilitate the direct
transfer of hydride anion. Which coenzyme is
required for this transfer?
A)
biotin
B)
folic acid
C)
lipoic acid
D)
TPP
E)
NAD+
6. Pyruvate + CoA + NAD+  __________ + CO2 +
__________
A)
oxaloacetate; ATP
B)
malonyl CoA; NADH + H+
C)
methylmalonyl CoA; biotin
D)
acetyl CoA; NADH + H+
E)
succinyl CoA; NAD+
7. What common structural element is present in the
coenzymes FAD, NAD+ and CoA?
A)
All contain a pyridoxal phosphate (PLP)
group.
B)
All contain a GDP group.
C)
All contain a nicotinamide group
D)
All contain an ADP group.
E)
All contain a TPP group.
8. What is the major role of NADPH in metabolism?
A)
Carrying electrons into the electron
transport pathway in mitochondria.
B)
Carrying electrons into the reduction
reactions of biosynthesis.
C)
Carrying high-energy phosphate groups
in ATP biosynthesis.
D)
Carrying high-energy phosphate hydride
groups in protein regulation.
E)
Carrying one or two electrons by a
semiquinone mechanism
9. Which of the following water-soluble vitamins forms
part of the structure of NAD+?
A)
Riboflavin
B)
Thiamine
C)
Pantothenate
D)
Pyridoxine
E)
Niacin
10.
11.
The driving force for the coupling of the electron
transport process to oxidative phosphorylation
of ADP is the creation of a protein gradient
across the
A)
Outer mitochondrial membrane
B)
Smooth endoplasmic reticulum
C)
Inner mitochondrial membrane
D)
Nuclear membrane
E)
Peroxisomal membrane
B)
C)
D)
E)
16.
Lipids are the biomolecules of choice for
storage of metabolic energy because they:
A)
are soluble in water
B)
yield a large amount of energy
upon oxidation
C)
are highly oxidized
D)
are easily hydrolyzed
E)
are amphipathic
17.
Which of the following is not a feature that a
micelle and a lipid bi-layer have in common?
A)
Both assemble spontaneously in
water.
B)
Both are made up of amphipathic
molecules.
C)
Both are very large, sheet-like
structures.
D)
Both have the thickness of two
constituent molecules in one of their
dimensions.
E)
Both are stabilized by hydrophobic
interactions, van der Waals forces,
hydrogen bonds, and electrostatic
interactions
18.
Membranes with unsaturated fatty acids in
their components are more flexible and fluid
because
A)
Unsaturated fatty acids pack closely
together to form ordered arrays.
B)
Unsaturated fatty acids bend at the
double bond preventing close
packing.
C)
Saturated fatty acids have a “kink”
that produces more fluid aggregates.
D)
Unsaturated fatty acids have cis
double bonds that makes it more
“sticky”.
E)
All of the above are correct.
Which of the following is not part of the electron
transport chain?
A)
NADH
B)
FADH2
C)
Coenzyme Q
D)
Coenzyme A
E)
FMNH2
12.
Proteins that phosphorylate other proteins are
called:
A)
protein phosphatases
B)
protein kinases
C)
peptidases
D)
protein hydrolases
E)
phosphotransferases
13.
Which of the following steps in glycolysis
constitutes an oxidation reaction?
A)
conversion of glucose to glucose 6phosphate
B)
conversion of phosphoenolpyruvate to pyruvate
C)
D)
E)
conversion of fructose 1,6diphosphate to glyceraldehyde 3phosphate
conversion of glyceraldehyde 3phosphate to 1,3-bisphosphoglycerate
conversion of 3-phosphoglycerate to 2phosphoglycerate
14.
In the citric acid cycle, Coenzyme A is a carrier
for
A)
phosphate groups
B)
carboxyl groups
C)
methyl groups
D)
hydride ions
E)
acetyl groups
15.
Fatty acids are all EXCEPT:
A)
either saturated or unsaturated
found seldom in free form
mostly found with an even number of
carbons
found in linear, branched and
cyclic forms
all are true
19.
20.
21.
22.
23.
24.
Cellulose and chitin are similar in all of the
following ways EXCEPT:
A)
Both are polymers of glucose.
B)
Both are structural polysaccharides.
C)
Both have extended ribbon
conformations.
D)
Both have extensive hydrogen bonding.
E)
All are true.
Proteoglycans are a group of macromolecules
formed from:
A)
proteases and monosaccharides.
B)
proteins and glycosaminoglycans.
C)
proteins and polysaccharides.
D)
proteases and glycosaminoglycans.
E)
proteins and glycogen.
The cytoplasmic membrane of bacteria
A)
retains the cytoplasm and its contents
B)
acts as a selectively permeable barrier,
allowing some molecules to pass while
preventing others.
C)
Is the major site of ATP synthesis in
aerobes.
D)
all of the above
Which of the following is not true of bacterial
plasmids?
A)
They can replicate independently of the
chromosome.
B)
They may carry genes of drug resistance.
C)
They are required for host growth
and/or reproduction.
D)
They may carry genes that enhance the
metabolic capabilities of the bacterium.
The lipopolysaccharide (LPS) found in the outer
membrane of gram-negative bacteria is also
known as
A)
exotoxin
B)
teichoic acid
C)
murein
D)
endotoxin
Gram-positive cells retain the primary stain
whereas gram-negative cells do not because
A)
B)
C)
D)
alcohol removes the outer membrane
and, therefore, the trapped stain from
gram-negative bacteria.
The alcohol shrinks the pores of the thick
peptidoglycan layer of gram-positive
cells, thereby trapping the stain.
A and B
None of the above
25.
Which of the following is true of capsules?
A)
They help bacteria escape phagocytosis
by host cells.
B)
They retain water and help prevent
desiccation of the bacteria.
C)
They prevent entry of many bacterial
viruses.
D)
All of the above
26.
The term used to describe bacteria that are
shaped like curved rods is
A)
coccus.
B)
Bacillus.
C)
Vibrio.
D)
Coccobacillus.
27.
Square planar arrangements of cells that forms
when round bacteria remain attached to each
other during reproduction are called
A)
streptococci
B)
staphylococci
C)
tetrads
D)
sarcinae.
28.
Proteins that are loosely attached to the
cytoplasmic membrane are called ________
proteins.
A)
peripheral
B)
integral
C)
external
D)
internal
29.
Proteins that are embedded within the
cytoplasmic membrane and not easily extracted
are called _________ proteins.
A)
peripheral
B)
integral
C)
external
D)
internal
30.
A feature unique to some archael plasma
membranes is that they may
A)
consist of a lipid bilayer that lacks
integral membrane proteins.
B)
Consist of a lipid bilayer with embedded
proteins.
C)
Contains sterols such as cholesterol.
D)
Consist of a lipid monolayer.
31.
Shrinkage of the plasma membrane away from
the cell wall with the bacterium is placed in a
hypertonic environment is called
A)
osmolysis.
B)
Plasmolysis
C)
Hyrolysis
D)
Hypertonolysis
32.
Although penicillin inhibits peptidoglycan
synthesis, bacterial cells will continue to grow
normally in the presence of penicillin in a(n)
____________ environment.
A)
hypotonic
B)
isotonic
C)
hypertonic
D)
nonpolar
33.
Mesosomes are
A)
photosynthetic organelles of bacteria.
B)
Found only in gram-negative bacteria.
C)
Invaginations of the plasma membrane
often found near septa or cross-walls.
D)
Found only in gram-positive bacteria.