Bio 2
Fall, 2009
***Multiple choice and matching in Part II are answered here.
We covered Part II in Activity
Bio 2
Exam 1
Total possible: 100 pts
Part I ______
Part II ______
Total ______
Part I. Multiple Choice. (One point each.) There should be just one correct answer for each of the
questions below. Please answer on a Scantron 882-E form.
1.
Which of the following is a false statement?
a.
b.
c.
d.
e.
2.
The lowest level of biological organization that can perform all the activities required for life is the
a.
b.
c.
d.
e.
3.
animal
archaea
fungi
d.
e.
protists
plant
Prokaryotic and eukaryotic cells generally have which of the following features in common?
a.
b.
c.
d.
e.
5.
organism - for example, an amoeba, dog, human, or maple tree.
organelle - for example, a chloroplast.
organ system - for example, the reproductive system.
tissue - for example, nervous tissue.
cell - for example, a muscle cell.
Which of the following types of cells utilize deoxyribonucleic acid (DNA) as their genetic material but
do not have their DNA encased within a nuclear envelope?
a.
b.
c.
4.
All forms of life are composed of cells that have a membrane-enclosed nucleus.
Every cell uses DNA as its genetic information.
DNA is the unit of inheritance that is transmitted from parent to offspring.
Every cell is enclosed by a membrane.
All of the above are true
linear chromosomes made of DNA and protein
flagella or cilia that contain microtubules
a cell wall made of cellulose
a membrane-bounded nucleus
ribosomes
How do the reductionist approach to science and the systems approach differ?
a.
b.
c.
d.
e.
The reductionist approach attempts to understand biology by breaking the complexity of
biology down to its fundamental components while systems biology just focuses on
understanding organ systems in animals.
The reductionist approach attempts to understand biology by breaking the
complexity of biology down to its fundamental components while systems biology
attempts to assemble the pieces we have examined using the reductionist approach
back together to understand biological complexity.
The reductionist approach applies only hypothesis-based studies while the systems
approach applies only discovery science.
All of the above are correct.
None of the above are correct.
6.
Most scientists agree that the most unifying theme in biology is that:
a. All organisms carry out energy conversion
b. All cells are enclosed by membranes
c. All cells use DNA as their hereditary material
d. That all life came about through evolution
e. None of the above
7.
What is a hypothesis?
a.
b.
c.
d.
e.
8.
Nitrogen has an atomic number of 7 and a mass number of 14. Thus, the atomic mass of an oxygen
[nitrogen] atom is
a.
b.
c.
d.
e.
9.
a fact based on qualitative data that is testable
a fact based on quantitative data that is falsifiable
a verifiable observation sensed directly, or sensed indirectly with the aid of scientific
instrumentation
the same thing as an unproven theory
a tentative explanation that can be tested and is falsifiable
exactly 7 grams.
approximately 14 grams.
approximately 14 daltons.
exactly 7 daltons.
21 amu (atomic mass units)
Calcium has an atomic number of 20 and an atomic mass of 40. Therefore, a calcium atom must have
a. 40 neutrons.
b. 20 protons.
c. 40 electrons.
d. 20 protons and 40 electrons.
e. 20 protons, 40 electrons, and 40 neutrons.
10. Carbon-12, carbon-13, and carbon-14 differ from each other in
a.
b.
c.
number of protons
number of neutrons
valence electron distribution
d.
e.
number of electrons
amount of radioactivity
11. If two atoms are joined by a polar covalent bond, the electrons that are shared in forming the covalent
bond are drawn more strongly to
a.
b.
c.
d.
e.
The atom that is less electronegative
The atom that is more electronegative
Neither, electrons are equally shared in all covalent bonds
The atom with the higher atomic number
It depends entirely on the other atoms in the molecule
12. For a pair of atoms that form an ionic bond:
a.
b.
c.
d.
e.
One loses an electron while the other gains an electron
The bond is also considered to be a highly polar covalent bond
The two atoms are held together by the attraction of opposite charges
The compound formed is likely to be water soluble
a, c and d are all correct.
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Bio 2
Fall, 2009
13. Sulfur, like oxygen, has six electrons in its outer shell. If an atom of sulfur (atomic number 16) were
allowed to react with atoms of hydrogen (atomic number 1), which of the molecules below would
be expected to form:
C and E are correct
a.
H
b.
|
H-S-H
|
H
d. S - H
H-S-H
|
H
c. H - S - H
e. H - S - H
14. What gives rise to the cohesiveness of water molecules?
a.
b.
c.
d.
e.
nonpolar covalent bonds
hydrophobic interactions
ionic bonds
hydrogen bonds
both hydrophobic interactions and ionic bonds
15. What is the difference between covalent bonds and ionic bonds?
a.
b.
c.
d.
e.
Covalent bonds involve the transfer of electrons between atoms, and ionic bonds involve
the sharing of neutrons between atoms.
Covalent bonds involve the sharing of neutrons between atoms, and ionic bonds involve
the sharing of electrons between atoms.
Covalent bonds involve the sharing of protons between atoms, and ionic bonds involve
the sharing of neutrons between atoms.
Covalent bonds involve the sharing of electrons between atoms, and ionic bonds involve
the electrical attraction between atoms.
Covalent bonds involve the sharing of protons between atoms, and ionic bonds involve
the sharing of electrons between atoms.
16. Why are hydrocarbons insoluble in water?
a.
b.
c.
d.
e.
They are lighter than water.
They exhibit considerable molecular complexity and diversity.
They are hydrophilic.
The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages.
The majority of their bonds are polar covalent carbon-to-hydrogen linkages.
17. Which of the following statements correctly compares water with other compounds?
a.
b.
c.
d.
e.
It takes more heat to raise the temperature of liquid water 1° than an equal volume of most other
liquids
Unlike most compounds, as a solid it is less dense than its liquid form
Liquid water forms more hydrogen bonds than most other liquids
More energy is required to cause vaporization than is required for most other liquids
All of the above are true
18. What is the pH of a solution with a hydrogen ion [H+] concentration of 10-10 M?
a.
b.
pH 2
pH 4
c.
d.
pH 10
pH 12
3
e.
pH 14
Bio 2
Fall, 2009
19. If the pH of a solution is decreased from 9 to 8, it means that the
concentration of OH- has increased 10-fold (10X) compared to what it was at pH 9.
concentration of H+ has increased 10-fold (10X) compared to what it was at pH 9.
concentration of H+ has decreased to one-tenth (1/10) what it was at pH 9.
concentration of OH- has decreased to one-tenth (1/10) what it was at pH 9.
concentration of H+ has increased 10-fold (10X) compared to what it was at pH 9 and concentration
of OH– has decreased to one-tenth (1/10) what it was at pH 9.
a.
b.
c.
d.
e.
20. The equilibrium relationship shown below shows the relationship between carbon dioxide (CO 2),
carbonic acid (H2CO3) and bicarbonate (HCO3-) in solution
H2O + CO2 ⇔ H2CO3 ⇔ HCO3- + H+
What effect should the increasing atmospheric CO2 levels we are current experiencing have
on the pH of the oceans?
a.
b.
c.
d.
e.
a decrease in the concentration of H2CO3 and an increase in the concentration of HCO3and H+.
an increase in the concentration of H2CO3 and a decrease in the concentration of H+.
a decrease in the concentration of HCO3- and an increase in the concentration of H +.
an increase in the concentration of HCO3- and an increase in the concentration of H +.
a decrease in the concentration of HCO3- and an increase in the concentration of both H+
and H2CO3.
21. The structures of glucose and fructose are shown above. These two molecules are
a.
b.
c.
d.
e.
geometric isotopes.
geometric isomers.
enantiomers.
nonisotopic isomers.
structural isomers.
22. A compound contains multiple hydroxyl groups as its predominant functional group. Which of the
following statements is likely true concerning this compound?
a.
b.
It lacks an asymmetric carbon, and it is probably a fat or lipid.
It should dissolve in water.
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Bio 2
Fall, 2009
c.
d.
e.
It is hydrophobic.
It should dissolve in a nonpolar solvent.
It won't form hydrogen bonds with water.
23. What is the name of the functional group shown in the figure below?
a.
b.
c.
aldehyde
ketone
carbonyl
d.
e.
24. Which of the following is true regarding sulfhydryl groups?
a.
The are non-polar
b.
They are basic in pH.
c.
They contain nitrogen.
d.
e.
hydroxyl
carboxyl
They participate in covalent
crosslinkages in proteins.
All of the above .
25. Which functional groups can act as acids?
a.
b.
c.
carboxyl and phosphate
ketone and amino
carbonyl and carboxyl
d.
e.
amine and sulfhydryl
hydroxyl and aldehyde
26. The enzyme amylase is present in our saliva and can break glycosidic linkages between glucose
monomers only if the monomers are the  form. Which of the following could amylase break down?
a.
b.
c.
cellulose
glycogen and cellulose
glycogen and starch
d. starch only
e. glycogen, cellulose and chitin
27. Which of the following descriptors is true of the molecule shown in the figure below?
a.
b.
c.
This is a hexose
This is a pentose
This is a purine
d.
e.
This is a pyrimidine
None of the above
28. Which of the following is true of starch, glycogen and cellulose?
a.
b.
c.
d.
e.
They are geometric isomers of each other.
They are all used for energy storage in plants.
They are all polymers of glucose.
They can all be digested by humans.
They are all composed of glucose molecules in  1-4 linkages.
29. Which of the following is true regarding saturated fatty acids?
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Bio 2
Fall, 2009
a.
b.
c.
d.
e.
They are usually liquid at room temperature.
They are usually produced by plants.
They are the predominant fatty acid in corn oil.
They have double bonds between carbon atoms of the fatty acids.
They are used in the synthesis of the fats in lard and butter.
30. Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits.
Which of the following is an exception to this statement?
a.
b.
c.
d.
e.
phospholipid
cellulose
an enzyme
DNA
a contractile protein
31. The molecule at the right is most likely a _________ that was synthesized in the _______
a.
b.
c.
d.
e.
Steroid, Smooth ER
Fatty acid, Peroxisome
Steroid, Lysosome
Carbohydrate, Rough ER
Nucleotide, mitochondria
32. At which bond would water need to be added to achieve hydrolysis of the peptide shown below to
yield its component amino acids?
a.
b.
A
B
c.
d.
C
D
33. The primary structure of a protein is its:
a.
b.
c.
d.
e.
Amino acid sequence
Local regions of organized structure such as alpha helices and beta sheets
Overall structure of each polypeptide
Complete structure of the protein that includes all subunits
All of the above
34. Which bonds are created during the formation of the primary structure of a protein?
a.
b.
c.
hydrogen bonds
phosphodiester bonds
peptide bonds, hydrogen bonds, and disulfide bonds
6
e.
E
d.
e.
disulfide bonds
peptide bonds
35. The  helix and the ß pleated sheet are both common polypeptide forms found in which level of
protein structure?
a. secondary
d. quaternary
b. tertiary
e. all of the above
c. primary
36. The R group or side chain of the amino acid serine is -CH2-OH. The R group or side chain of the amino acid
alanine is -CH3. Which of these amino acids would you expect to find in the portion of a protein that is
embedded in a membrane?
a.
b.
c.
d.
e.
Serine since it is hydrophilic
Serine since it is hydrophobic
Alanine since it is hydrophilic
Alanine since it is hydrophobic.
Neither since proteins aren’t in membranes.
37. The figure at the right best illustrates the
a.
b.
c.
d.
e.
primary structure of a polysaccharide.
quaternary structure of a protein.
double helix structure of DNA.
secondary structure of a polypeptide.
tertiary structure of a polypeptide.
38. How does pH affect protein structure?
a. By disrupting hydrogen bonds between base pairs
b. By causing the charge of some side chains to change which then affects the overall
structure
c. Since all amino acids include carboxyl groups and amino groups, the charge on each
individual amino acid may change
d. By causing the hydrolysis of peptide bonds
e. All of the above
39. Heating double-stranded DNA to a high enough temperature will cause the two strands to melt. In
other words, it causes the two strands to separate. What types of bonds are being broken (melted) for
this to occur?
a. Polar covalent bonds
b. Phosophodiester bonds
c. Non-polar covalent bonds
d. Ionic bonds
e. Hydrogen bonds
7
40. Which of the following statements about the 3' end of a polynucleotide strand of DNA is correct?
a.
b.
c.
d.
e.
The 3' end has a carboxyl group attached to the number 3 carbon of ribose.
The 3' end has a phosphate group attached to the number 3 carbon of ribose.
The 3' end is the third position on one of the nitrogenous bases.
The 3' end is the point of addition of incoming nucleotides as DNA is synthesized
All of the above.
41. How do A-T and G-C base pairs differ from each other?
a.
b.
c.
d.
e.
A-T bases are both purines while G-C bases are both pyrimidines
There are 2 covalent bonds joining A-T base pairs and 3 covalent bonds joining G-C base
pairs
There are 2 hydrogen bonds joining A-T base pairs and 3 hydrogen bonds joining G-C
base pairs
A-T base pair contain ribose while G-C base pairs contain deoxyribose
All of the above
42. What is the structural feature that allows DNA to be accurately replicated?
a.
b.
c.
d.
e.
The three-component structure of the nucleotides
disulfide bonding (bridging) of the two helixes
complementary pairing of the A-T and G-C base pairs
twisting of the molecule to form an alpha helix
the sugar-phosphate backbone
43. All of the following are part of a prokaryotic cell except
a.
b.
c.
DNA.
RNA.
ribosomes
d.
e.
nuclear envelope
a plasma membrane.
44. A cell that contains a large amount of smooth ER could be specialized to do which of the following:
a.
b.
c.
Synthesize starch
Synthesize proteins
Degrade toxins
d.
e.
Synthesize glycoproteins
All of the above
45. Which structure is the site of the synthesis of proteins that may be exported from the cell?
a.
b.
c.
mitochondria
smooth ER
rough ER
d.
e.
Golgi apparatus
lysosomes
46. The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following
statements correctly describes this polarity?
a.
b.
c.
d.
e.
Proteins in the membrane of the Golgi may be sorted and modified as they move from
one side of the Golgi to the other.
Lipids in the membrane of the Golgi may be sorted and modified as they move from one
side of the Golgi to the other.
Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as
they move from one side of the Golgi to the other.
Transport vesicles fuse with one side of the Golgi and leave from the opposite side.
All of the above correctly describe polar characteristics of the Golgi function.
8
47. In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular
components. Which organelle functions in this compartmentalization?
a.
b.
c.
central vacuole
lysosome
peroxisome
d.
e.
chloroplast
centrosome
48. Membrane enclosed organelles other than the nucleus that contain DNA include
a.
b.
c.
d.
e.
mitochondria and chloroplasts only
chloroplasts.
ribosomes, mitochondria, and chloroplasts
ribosomes.
mitochondria.
49. A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and
mitochondria. It could be a cell from
a.
b.
c.
any kind of organism.
a bacterium.
an animal, but not a plant.
d.
e.
a plant, but not an animal.
a plant or an animal.
50. Most animal cells contain members of each class of cytoskeletal element. Some cells have greater
amounts of one type of cytoskeletal element or specialized types of each of these so that they can
perform their function well. One important role of our skin is to provide a strong barrier against the
environment. Which cytoskeletal element is a key component of skin and provides it with its strength
to resist tearing?
a. Microfilaments
b. Intermediate filaments
c. Microtubules
d. Actin filaments
e. All of the above
51. Muscle cells are able to contract with great force. Which cytoskeletal element works with myosin
motors to enable muscle cells to contract?
a. Microfilaments
b. Intermediate filaments
c. Microtubules
d. Actin filaments
e. Both a and d
52. The nuclear lamina, which is located in the nucleus, provides structural support and may also act as a
scaffold to help organize chromosomes. Of what cytoskeletal is it composed?
a. Microfilaments
b. Intermediate filaments
c. Microtubules
d. Actin filaments
e. All of the above
53. Where in the cell would you be most likely to find motor proteins?
a. In the nucleus where they move chromosomes
b. Inside the ER
c. In mitochondria and chloroplasts
d. Attached to all cytoskeletal elements
e. Attached to microtubules and microfilaments
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Part II.
1.
(5 pts.) Identify each of the functional groups shown below:
A. ______________________________
B. ______________________________
C. ______________________________
D. ______________________________
E. ______________________________
Refer to the structures below to answer the questions that follow. There may be more than one correct
answer for each question. Write “none” if there are no matches.
2. (12 pts) Which of the above are:
amino acids __2, 7, 8______
fatty acids __9_____
ribose ____12_____
polysaccharides __14__
phospholipids ___5____
nitrogenous bases __13__
10
deoxyribose __none__
hexoses _1, 4, 6____
3.
(4 pts) Glycine is the simplest amino acid--the R group is a hydrogen atom. Draw the structure of this
amino acid.
4.
(6 pts) Now draw two glycine molecules linked together by a peptide bond. On this molecule, label
the N-terminus, the C-terminus and the peptide bond.
5.
(2 pts) During protein synthesis in the cell, to which end of the growing polypeptide are amino acids
added?
6.
(3 pts) Where are proteins that are soluble in the cytoplasm normally synthesized?
7.
(5 pts) Which membrane-bound organelles make up the endomembrane system?
8.
(4 pts) a. If a protein is glycosylated (i.e. has sugar groups added to it) where would these first be
added to the protein?
b. Are these sugars exposed to the cytosol, the outside of the cell, or is it equally likely to find
them exposed to the cytosol or outside of the cell?
9.
(6 pts) Many cells have specialized functions and, in many cases, we observe a proliferation of
organelles that are necessary for that function. For each of the following:


list the organelles that you expect to find in increased amounts. and
identify the function(s) that the organelles are performing in these cells.
(Be thorough—a total of 4 bonus points are possible here for thorough answers).
a.
A white blood cell engaged in phagocytosis of a pathogen:
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b.
Liver cells from an individual being treated with large amounts of drugs:
c.
An animal muscle cell:
12