C. If the pH of a cytoplasmic compartment falls from 7.0 to 6.0 then:

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• 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)
• NOTE MEMBRANE STRUCTURE AND FUNCTION WILL BE ON
  THE EXAM
• These are dry-runs for the Exams you will take.
  The questions here ARE exam questions from
  previous years (thats why the jokes are so out
  of date). You will see questions similar to
  these on Sept 23 (with fresher jokes).
• Section I. MULTIPLE, Multiple Choice.
• Rarely is there just one right answer in life.
  These questions are designed to explore the
  different characteristics of individual things,
  processes or properties. Practice looking for
  ALL possible characteristics of an item while you
  are studying your notes.
• Indicate all of the answers below that correctly
  relate to the questions in bold type. Note
  there is frequently more than one right answer!
  Sometimes there IS only one correct choice, other
  times none of the choices are correct, or all may
  be correct. Think of this as a type of
  true-false choice for each possible answer to
  the question. When you fill out the bubble
  answer sheet column 1 will be true, column 2
  will be false. On the the practice exam
• below, you have 200 answer choices so each
  choice is worth 0.5 pt that is, if you say it is
  correct and it is, you get 0.5 pt if you dont
  say it is correct and it is, you lose 0.5 pt,
  etc. We the actual exam will probably be shorter
  (have less answer choices, like 150), so each
  choice will be worth more (like 0.67 pt). You
  only have 50 min for the 9/23 exam.

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
 
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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.
6 7 9 10 13
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
15 18
2
D. Which of the following biologically-important
linkages are the result of condensation/dehydratio
n reactions 20) peptide bonds 21) ester
linkages 22) phosphodiester bond 23) James
Bond 24) hydrogen bonds 25) Van der Waals
interactions 26) Glycosidic bonds
20 21 22 26
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.
27 28
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  
31 33
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
36 37 38 42 43
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
45 46 47 49
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• Intracellular membrane-bound organelles
• 50) Are typically observed in Prokaryotes
• 51) Comprise distinct compartments within the
  cytoplasm
• 52) Are the cells lock boxes
• 53) Include mitochondria
• 54) are typically observed in Eukaryotes
• 55) include the Golgi Apparatus
• 56) include the endoplasmic reticulum
• 57) include ribosomes
• 58) include nuclei (plural of nucleus)
• 59) contain phospholipids in their membranes
• 60) allow different functions to occur in a cell
  at the same time
• 61) allow different microcompartments within the
  cell to have distinct internal pHs
• 62) allow the cell to maximize effective surface
  area

51 53 54 55 56 58 59 60 61 62
J. Water has a tendency to 63) Form hydrogen
bonds with polar molecules 64) Form hydrogen
bonds with non-polar molecules 65) Form four
oxygen bonds with carbon molecules 66) ionize and
form the charged species OH and H 67) Form
hydrogen bonds with hydrocarbon chains
(R-CH2-CH2-CH2-CH3) 68) Form hydrogen bonds with
amino groups (R-NH2) 69) Bomb Iraq 70) Let the
weapons inspectors do their job
63 66 68
K. A Carbon atom always makes this number of
covalent bonds 71) one 72) two 73) four 74)
eight
73
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
75 76 78
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• Which of the following is a membrane-bound
  organelle?
• 80) ribosome
• 81) nucleus
• 82) triglyceride
• 83) microtubule

80
N. A covalent bond between a carbon and a
hydrogen atom is considered 84) nonpolar 85)
polar 86) ionic 87) ironic 88) romantic
84
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
91
P. A carboxylic acid group with a pKa of
5.5 93) Will be ionized at pH 7.0 94) Will be
uncharged at pH 7.0 95) Will be uncharged at pH
4.0 96) Will be uncharged at pH 8.8 97) Will bear
a negative charge in a solution that has 1x10-10
M OH ions 98) Can form a condensation reaction
with an alcohol group to form an ester bond 99)
Is hydrophilic
93 95 98 99
Q. Which of the following components are found
in prokaryotes (bacteria and cyanobacteria)? 100)
plasma membrane 102) nucleus 103) endoplasmic
reticulum 104) golgi
apparatus 105) ribosomes 106) DNA 107) bloody
gloves 108) mitochondria 109)
chloroplasts 110) lysosomes 111) Bruno Magli
shoes
100 105 106
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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.
112 113 115 116
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 123) Threonine 124) deoxyRibose

121 124
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.
129 130
U. Which of the following structures represents a
monosaccharide?
131) C12H22O11
132)
133)
HO C O H C OH
H C OH H
132
134)
V. An alpha helix ( a-helix ) 135) Is a
primary structure 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
136
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W. Which of the following are considered
hydrophobic amino acids with hydrophobic R
groups 140) glucose 144) serine 148)
palmitic acid   141) leucine 145)
valine   142) phenylalanine 146)
glutamine   143) adenine 147)
lysine  
141 142 145
1.    
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 Lewinskis
dress
150 154 155 156
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 (lets 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
158 161 162 165
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Z. The monomers which make up a polypeptide
are 167) held together by phosphodiester
bonds 168) chiral 169) nitrogenous bases 170)
unsaturated 171) nucleotides 172) amino
acids 173) monosaccharides 174) interns
168 172
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
176 178
182 183 184
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 CC. Familiarity with the properties of water
is important to understand 185) Why polymers
adopt the secondary and tertiary structures they
do 186) How soap works 187) What chirality
is 188) What a lock box is 189) Why we need a
tax cut (didnt Reagan try this already?) 190)
Why some hydronium (H) ions and hydroxide (-OH)
ions are always present for reactions in
water 191) Why hydrophilic polymers tend to
hydrogen bond with themselves rather than
water 192) Who this Chad guy is 193) How Chad
got pregnant. 194) Why membranes form in
water 195) Why carbon atoms can form covalent
bonds with 4 other atoms
185 186 190 191 194
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
199 200
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.
B C E