Name ____________________ BCOR 011 Vayda/Stratton Sept 14, 2005 PRACTICE EXAM QUESTIONS Lectures 1, 2 & 3 (Bonding & Functional Groups, Water, pH & Hydrophobicity, Carbohydrates, Lipids, Nucleic Acids &n Proteins, Cell Tour)
A. The structure at right:
1) is a -sheet (beta)
2) is a base pair
3) is a micelle
4) is a starch grain
5) is an polysaccharide
B. The tertiary structure of a protein is:
6) the overall 3-D structure of the protein.
7) dictated by interactions of amino acid R-groups with one another.
8) dictated by interactions of the N-terminus with the C-terminus of the polypeptide.
9) influenced by the presence of disulfide bonds.
10) influenced by hydrophobic interactions.
11) the interaction of two or more polypeptide chains to form a protein complex.
12) the interaction of individual amino acids with one another to form a polypeptide.
13) dictated by how the surfaces of secondary structures interact with one another.
C. If the pH of a cytoplasmic compartment falls from 7.0 to 6.0 then:
14) the gloves must fit
15) the amount of H+ (hydronium) ions has increased
16) the amount of -OH (hydroxide) ions has increased
17) an acid with a pKa of 4.2 will lose its negative charge
18) a base with a pKb of 6.8 will become positively charged
19) phosphate functional groups will become positively charged
D. Which of the following biologically-important linkages are the result of condensation/dehydration reactions:
20) peptide bonds
21) ester linkages
22) phosphodiester bond
23) James Bond
24) hydrogen bonds
25) Van der Waal’s interactions
26) Glycosidic bonds
E. Covalent bonds:
27) are formed when two atoms share electrons.
28) enable atoms to form molecules with stable, precise spatial configurations
29) give the molecule a positive charge at high pH
30) can be purchased through your stockbroker.
F. Atoms interact to attain chemical stability by:
31) sharing electrons to form covalent bonds
32) sharing the Oval Office
33) “stealing” electrons to complete a stable outer electron shell
34) forming micelles
35) sharing intimate secrets with Linda Tripp
G. Chiral carbons:
36) are found in carbohydrate polymers
37) are found in amino acids
38) are found in polypeptides
39) were found at Rockingham
40) are found in saturated fatty acids
41) are found in water
42) are found in DNA
43) have 4 different functional groups attached to them
44) cannot interact with water
H. Amino acids:
45) as monomers, can be expected to be ions at pH 7.0
46) with non-polar “R” groups include alanine, valine and leucine.
47) can be joined in linear polymers to form polypeptides.
48) were allegedly used by Nicole and Faye Resnick
49) with alcohols for “R” groups include threonine and serine
K. A Carbon atom always makes this number of covalent bonds:
L. Eukaryotic cells differ from prokaryotic cells in that eukaryotic cells:
75) are typically much larger than prokaryotic cells
76) contain internal membranes and membrane bound organelles whereas
prokaryotic cells typically do not
77)) store their genetic information in the DNA whereas prokaryotic cells use RNA to store genetic information
78) have nuclei whereas prokaryotic cells do not
79) have viruses whereas prokaryotic cells do not
N. A covalent bond between a carbon and a hydrogen atom is considered:
O. A solution with a pH of 5 :
89) has a hydrogen ion concentration of 1x10-9M
90) has a water concentration of 5 M
91) has a hydrogen ion concentration of 0.00001M
92) cannot form hydrogen bonds
Q. Which of the following components are found in prokaryotes (bacteria and cyanobacteria)?
100) plasma membrane
103) endoplasmic reticulum
104) golgi apparatus
107) bloody gloves
111) Bruno Magli shoes
R. Carbohydrate polymers are polar molecules which tend to:
112) be insoluble in water.
113) hydrogen bond with themselves rather than water.
114) form micelles which are great for cleaning greasy dishes.
115) be slimy, gooey or gelatinous when forced to be fully hydrated by water.
116) serve as recognition markers on external surfaces of membrane proteins.
117) hydrolyze peptide bonds.
S. Which of the following components are usually found in DNA:
118) phosphatidyl Choline
119) Glutamic acid
120) the preservative EDTA
121) Adenosine monophosphate
122) phosphatidyl Inositol
T. Phospholipids tend to:
125) form aromatic rings.
126) be solids at room temperature if comprised of unsaturated fatty acids.
127) form cholesterol.
128) be hydrolyzed to cholesterol and wax.
129) form bilayers and vesicles.
130) bear a negative charge at pH 7.0.
U. Which of the following structures represents a monosaccharide?
HO – C = O
H – C – OH
H – C – OH
V. An alpha helix ( a-helix ) :
135) Is a “primarystructure” that a polypeptide can adopt
136) Is formed when one polar peptide bond hydrogen bonds with another peptide bond further down the chain
137) is held together by disulfide bonds
138) Is the covalent bonding arrangement that holds two polypeptides into a quaternary structure
139) Is a secondary structure of DNA and other polynucleotide chains
W. Which of the following are considered “hydrophobic” aminoacids with “hydrophobic”
140) glucose144) serine148) palmitic acid
141) leucine145) valine
142) phenylalanine 146) glutamine
143) adenine147) lysine
X. The molecule below :
149) is the L form of an amino acid
150) is likely to be a liquid oil
151) is a pentose
152) is likely to bear a negative (-) charge at pH 7.0
153) is a trisaccharide
154) is comprised of one or more unsaturated fatty acids
155) is hydrophobic
156) was found on Monica Lewinski’s dress
Among other things
Note: will never take off for a “joke” answer
Y.The SECONDARY STRUCTURE of DEOXYRIBONUCLEIC ACID (DNA) polymer:
157) Is formed by linking ATP mononucleotides together
158) Is a double-helix of anti-parallel strands
159) Is an alpha (a) helix of two parallel strands
160) Is a beta (b) helix of two anti-parallel strands
161) Is stabilized by precise hydrogen bonding of complementary “bases” trapped in a non-polar microenvironment; A with T, G with C
162) Is driven by the need for hydrophobic bases to stack on top of one another
163) Is driven by the insatiable desire for Bill Clinton to stack… (let’s not go there)
164) Is driven by the political motives of Kenneth Starr
165) Has the negatively (-) charged phosphate groups on the outside, exposed to water
166) is maintained “fluid” by the presence of unsaturated fatty acids in the polymer
BB. Which of the following amino acids has a hydrophilic R-group ?
181) isoleucine 182) threonine 183) arginine 184) glutamic acid
Z. The monomers which make up a polypeptide are:
167) held together by phosphodiester bonds
169) nitrogenous bases
172) amino acids
AA. Cellulose and Amylose (starch):
175) both contain the exact complement of amino acids but arranged in different orders
176) are both polymers of D-glucose but monomers of one are bound together by a1-4 glycosidic linkages whereas the other is bound together by b1-4 glycosidic linkages
177) are both polysaccarides, but one is hydrophobic and the other is hydrophilic
178) are polymers comprised of glucose but have very different 3-D shapes
179) are amphipathic molecules
180) are buffers which can bind ATP
DD. A molecule that is Chiral has :
196) an unshared pair of electrons
197) a pH of 7
198) hydrophobic character
199) a left-handed and right-handed form
200) at least one carbon with four different functional groups bonded to it
2. The fluid mosaic model of membranes predicts that:
a) O.J. did it.
b) phospholipids are free to move laterally in membranes.
c) proteins are free to move laterally in membranes.
d) fluids are free to pass through membranes but solid particles cannot.
e) polypeptides are embedded in a sea of phospholipids.
f) polymers of a-D-glucose are soluble in water whereas polymers of b-D-glucose are not.