Ch 1: Cell & Molecular Biology Flashcards
(169 cards)
1
Q
Which of the following in considered a nonpolar amino acid?
A
Alanine
2
Q
Which of the following in considered a basic amino acid?
A
Lysine, Arginine, Histidine
3
Q
Which of the following is considered a polar, but uncharged amino acid?
A
glutamine
4
Q
Which of the following amino acids has a negatively charged side chain at physiological pH?
A
Aspartic acid
5
Q
Which of the following are consumed or produced during the formation of a six amino acid long polypeptide formed from individual amino acid?
A
5 H2O produced
6
Q
Which of the following is not a function of proteins?
A
main component of cell membranes
7
Q
Which of the following is responsible for maintaining the structure of an alpha helix?
A
hydrogen bonding
8
Q
Which of the following is responsible for maintaining the tertiary structure of a protein?
A
Dipole dipole forces, hydrogen bonding, covalent bonding, hydrophobic effect
9
Q
Which of the following is not a disaccharide?
A
fructose
10
Q
Chitin consists of repeating units of
A
beta-glucose
11
Q
Lactose consists of which pairs of monomers?
A
glucose-galactose
12
Q
Which of the following polymers is found typically in the exoskeleton of invertebrates?
A
chitin
13
Q
This polysaccharide serves as a store of glucose in liver and muscle cells.
A
glycogen
14
Q
Amylose and amylopectin comprise this storage polysaccharide in plants
A
starch
15
Q
What type of bond joints two monosaccharides together?
A
glycosidic
16
Q
A molecule of DNA consists of two complementary strands, these are joined together by__.
A
hydrogen bonds
17
Q
The “backbone” of a DNA molecule is made up of __
A
both sugar and phosphate
18
Q
How many hydrogen bonds from between the nucleotides Guanine and Cytosine?
A
3
19
Q
RNA contains which nitrogen bases?
A
Adenine, Uracil, Guanine, Cytosine
20
Q
A section of DNA with the sequence 3’-ATAACGGTACC-5’ is transcribed into mRNA. Which of the following shows the correct mRNA sequence?
A
3’-GGUACCGUUAU-5’
21
Q
Which of the following sugars is found in a molecule of RNA?
A
ribose
22
Q
A single nucleotide contains__
A
sugar + phosphate + nitrogenous base
23
Q
A single nucleoside contains__
A
sugar + nitrogenous base
24
Q
In, DNA nucleotides are joined by which type of bond?
A
phosphodiester
25
Of the bases Adenine (A), Thymine (T), and Cytosine (C), __ are purines and __ are pyrimidines
A&G, C&T
26
DNA molecules are most commonly __, and RNA is usually__
double stranded, single stranded
27
Compared with DNA, RNA has an additional __, which makes RNA relatively__
2' OH, less stable
28
A fatty acid and glycerol are joined together by which type of bond?
ester bond
29
The main structural difference between saturated and unsaturated fats in __
saturated fats contain all carbon carbon single bonds whereas unsaturated facts contain one or more carbon carbon double bonds
30
A phospholipid consists of__
a phosphate group "head" and hydrocarbon "tails"
31
Which of the following best described a phospholipid?
the tails of the molecule are hydrophobic while the head of the molecule is hydrophilic
32
Which of the following is correct regarding the formation of one triglyceride molecule from glycerol and three fatty acids?
3 molecules of water are produced
33
Which of the following is not derived from cholesterol?
vitamin C
34
Which of the following is not a lipid?
Albumin
35
Oils are fats which are lipids at room temperature. Fats and oils with relatively low melting temperatures have __ fatty acids chain length and a __ degree of unsaturation than those with higher melting temperatures
shorter, higher
36
Enzymes increase the rate of biological reactions by __
lowering the activation energy for the reaction
37
Which of the following statements is true regarding how enzymes affect the rate of a reversible reaction?
enzymes increase the rate of both forward and reverse reactions but do not affect the position of equilibrium
38
For an enzyme that follows Michaelis Menten kinetics, which of the following represents the rate of reaction, V, in terms of (S)?
V= Vmax (S)/ Km + (S)
39
A low value of the Michaelis Menten constant, Km means _
strong substrate binding by enzyme
40
A competitive inhibitor binds to which of the following sites on an enzyme?
active site
41
Competitive inhibitors reduce the effectiveness of an enzyme by __
blocking the active site
42
The effect of competitive inhibition can be overcome by __
increasing the concentration of the substrate
43
The effect of a noncompetitive inhibitor can be overcome by __
noncompetitive inhibition cannot be easily overcome
44
Which of the following best describes the structure of the nuclear membrane?
a double phospholipid bilayer
45
The gel like aqueous substance which surrounds organelles and suspends particles in the cell is known as the __
cytosol
46
Which of the following is not part of the cytoplasm of eukaryotes?
nucleus
47
Ribosomal RNA is synthesized __
in the nucleolus
48
Ribosomes are composed of __
RNA and proteins
49
Which of the following molecules does not cross the nuclear envelope?
DNA
50
Which of the following statements is correct regarding the nucleolus?
the nucleolus is not separated from the nucleus by a membrane
51
Which of the following are not true organelles?
cytoplasm, nucleolus
52
All of the following are included in the cytoplasm expect?
nucleolus
53
The general function of the golgi apparatus is__
sorting and packaging of proteins into vesicles
54
Which of the following is incorrect regarding the golgi body?
it is attached to the nuclear envelope
55
The function of the centrosome is __
structure and organization of the spindle apparatus
56
Which of the following would not be found in plant cells?
centrosomes
57
Which of the following organelles/ structures contains ribosomes either within the organelles interior or attached to the membrane exterior?
mitochondria, nucleus, rough endoplasmic reticulum
58
The result of lysosomal enzymes leaking into the cytosol is __
no significant effect
59
Microtubules are composed of which of the following proteins?
tubulin
60
Which of the following provide structural support for cells and help them to maintain their shape?
intermediate filament
61
The spindle apparatus is made up of __
microtubules
62
Which of the following is not part of the cytoskeleton?
cytosol
63
In addition to supporting the cell, which of the following processes does the cytoskeleton function in?
cell division and motility
64
Which of the following is a function of peroxisomes?
break down of fatty acids
65
The major function of peroxisomes in fatty acid catabolism. Which of the following is also broken down in peroxisomes?
D-amino acids
66
plant cell walls are composed of __
cellulose
67
Bacterial cell walls are composed of __
peptidoglycans
68
Fungal call walls are composed of __
chitin
69
Archea cell walls are composed of __
polysaccharides
70
In plant cells, starch is stored in __
storage vacuoles
71
Which of the site of photosynthesis in plant cells?
chloroplast
72
During which phase of the cell cycle are spindle fibers attached to kinetochores of chromosomes?
M
73
During which phase of the cell cycle does DNA replication occur?
S
74
Which phase of the cell cycle is the primary growth phase?
G1
75
In the G0 phase __
cell cycle progression is paused
76
Which of the following shows the correct order of the phases of the cell cycle?
G1, S, G2, M
77
A cell which is in the G0 phase of the cell cycle is __
inactive
78
Division of the cytoplasm during mitosis is known as __
cytokinesis
79
The product of mitosis is __
two identical diploid cells
80
In which of the following cells would mitosis not occur?
sperm cells
81
How many times does cytokinesis occur during mitosis?
1
82
G1, S, and G2 phases are a part of __?
interphase
83
Which of the following are microtubules organizing centers?
centrosomes
84
The function of microtubules organizing centers in mitosis is __
formation of spindle fibers
85
Mitotic spindle fibers are composed of __
tubulin
86
During which. mitotic phase does chromatin condense into chromosomes?
prophase
87
Spindle fibers begin to form during __
prophase
88
Mitotic spindle fibers connect to __
kinetochores
89
Most cells spend the greatest amount of time in __
interphase
90
Centromeres are __
the region of chromosomes where sister chromatids are joined together
91
Kinetochores are __
a complex of proteins which bind to the centromeres of chromosomes during cell division
92
Centrosomes are __
organelles which form the spindle fibers during mitosis
93
The cleavage furrow refers to __
the indentation in the cell surface which forms at the start of cytokinesis
94
During mitosis, the two centrioles move to opposite ends of the cell during __
prophase
95
Sister chromatids are pulled to opposite ends of the cell during __
anaphase
96
Nuclear division occurs during __
telophase
97
During mitosis, disjunction refers to __
the separation of sister chromatid to opposite ends of the cell
98
Which of the following structures causes chromosomes migration during mitosis?
spindle fibers
99
The product of meiosis is __
four non identical haploid cells
100
How many rounds of cytokinesis occur during meiosis?
2
101
Which of the following occurs in meiosis but not in mitosis?
homologous chromosomes line up in pairs along the metaphase plate
102
A pair of homologous chromosomes conjoined during meiosis I is called a __
tetrad
103
A bivalent refers to which of the following?
a pair of homologous chromosomes
104
Crossing over occurs during which phase of meiosis?
prophase I
105
The region where homologous chromosomes overlap and exchange genetic material in meiosis is known as __
chiasma
106
The pairing of homologous chromosomes during meiosis is known as __
synapsis
107
Which of the following processes does not occur during meiosis I?
migration of sister chromatids to opposite poles of the cell
108
Recombination refers to which of the following processes?
the exchange of DNA between homologous chromosomes during crossing over
109
The nuclear envelope breaks down and disappears during which phases of meiosis?
prophase I and prophase II
110
Uncoupling and separation of homologous chromosomes occurs during which phase of meiosis?
anaphase I
111
Migration of sister chromatids to opposite poles of the cell occur during which phase of meiosis?
anaphase I
112
Which of the following accurately represents the relationship between the terms catabolism, metabolism, anabolism, and energy transfer?
metabolism= catabolism + anabolism + energy transfer
113
Catabolism involves the __
breakdown of larger molecules into smaller molecules
114
Which of the following molecules are not used to transfer energy in metabolism?
H2O
115
Most of the energy stored in ATP is found within which type of bond?
phosphate phosphate
116
The movement of hydrogen ions across the mitochondrial inner membrane down their concentration gradient to power ATP synthesis is known as __
chemiosmosis
117
Which of the following is the site of the Krebs Cycle of cellular respiration?
mitochondrial matrix
118
Which of the following is correct regarding the pH of the mitochondrial matrix and the intermembrane space?
the intermembrane space has a lower pH than the mitochondrial matrix
119
Which of the following is a final product derived from glucose in glycolysis?
pyruvate
120
Which of the following enzymes catalyzes the first step of glycolysis?
hexokinase
121
Which of the following shows the next yield of high energy molecules from glycolysis per molecule of glucose?
2 ATP, 2 NADH
122
Which of the following represents the correct chemical equation for the aerobic respiration of glucose?
C6H12O6 + 6O2 --> 6CO2 + 6H2O
123
Which of these stages of cellular respiration do not occur in the mitochondria?
glycolysis
124
Which of the following shows the net yield of high energy molecules from the citric acid cycle per molecule of acetyle coA?
1 ATP, 3 NADH, 1 FADH2
125
Which of the following is reduced during glycolysis?
NAD+
126
Which of the following is the product of oxidative decarboxylation of alpha-ketoglutarate in aerobic respiration?
succinyl-CoA
127
Aerobic respiration involves the __ of oxygen into __
reduction, H2O
128
Which of the following steps in glycolysis is the major regulatory step?
phosphoenolpyruvate --> pyruvate
129
ATP hydrolysis is __
exergonic
130
Which of the following shows substrate-level phosphorylation?
ADP + Pi --> ATP
131
Which of the following describes the function of hexokinase in cellular respiration?
phosphorylation of glucose
132
How many of molecules of ATP are hydrolyzed per molecule of glucose during glycolysis?
2
133
Which of the following describes the function of phosphofructokinase- 1 (PFK-1) in glycolysis?
phosphorylation of fructose -6- phosphate
134
Which of the following describes the function of the pyruvate dehydrogenase complex in cellular respiration?
decarboxylation of pyruvate
135
Which of the following is a product of the reaction catalyzed by the pyruvate dehydrogenase complex?
acetyl-CoA
136
Which of the following describes the function of cristae in mitochondria?
increase the surface area for electron transport
137
Which of the following is correct regrading energy resulting from NADH and FADH2 via the electron transport chain?
NADH results in more energy than FADH2
138
Which of the following drives ATP production in the electron transport chain?
formation of an H+ gradient across the mitochondrial inner membrane
139
Coenzyme Q carries electrons between __ in the electron transport chain
complex II and complex III
140
Cytochrome C carries electron between __ in the electron transport chain
complex III and complex IV
141
At complex I in the electron transport chain, NADH is __
oxidized
142
Which of the following is/are the final products of alcohol fermentation?
ethanol + CO2
143
Which of the following macromolecules store the greatest amount of energy per gram?
fats
144
Phosphofructokinase-1 is activated by __ and inhibited by __
insulin, glucagon
145
Which of the following store significant amounts of glycogen?
liver, muscles
146
Which of the following activates the conversion of glucose into glycogen?
insulin
147
Which of the following activates the conversion of glycogen into glucose?
glucagon
148
Where are fatty acids concerted into acetyl coA?
mitochondria of liver cells
149
Photosynthesis occurs in which of the following structures in plant cells?
chloroplasts
150
Chlorophyll is found in which of the following structures in chloroplasts?
Thylakoid
151
The function of chlorophyll and carotenoids in plants is __
absorption of light energy by electrons
152
The most abundant light absorbing pigment is plants is __
chlorophyll a
153
Which of the following ions is found at the center of a chlorophyll molecule?
Mg2+
154
The structure of chlorophyll is derived from which of the following cyclic structures?
porphyrin
155
Photosynthesis is initiated by the absorption of light by __
photosystem II
156
The products resulting from noncyclic photophosphorylation is/are __
ATP and NADPH
157
The first reaction is photosynthesis is/are the __ reactions
light dependent
158
The photon absorbing pigments in photosystem I is
P700
159
The photon absorbing pigment in photosystem II is
P680
160
Compared with PSI, PSII absorbs light of __ frequency and __ wavelength
higher, shorter
161
The electrons donated by chlorophyll to the electron transport chain are replaced by which of the following?
H2O
162
Which of the following proteins forms ATP in photosynthesis?
ATP synthase
163
In which of the following chloroplast structures does the process of chemiosmosis occur?
thylakoid membranes
164
ATP production in the thylakoid of chloroplasts is driven directly by which of the following?
H+ gradient across the thylakoid membrane
165
Which of the following molecules is produced in both cyclic and non cyclic photophosphorylation?
ATP
166
Six turns of the Calvin cycle produce how many molecules of glyceraldehyde 3 phosphate?
2
167
NADPH produced in non cyclic photophosyphorylation is used __
to form glucose from CO2 in the calvin cycle
168
The first step in the calvin cycle is __
fixation of CO2
169
Which of the following steps of photosynthesis does photorespiration compete with?
carbon fixation
