FINAL Flashcards
(556 cards)
1
Q
true or false: monomers of macromolecules are joined together by hydrolysis reactions
A
false
2
Q
true or false: the liquid form of water (H2O) is more dense, than the solid form of water
A
true
3
Q
true or false: cations are negatively charged atoms that have fewer protons than electrons
A
false
4
Q
true or false: the “R-“ group of an amino acid has the greatest influence on the overall structure of a protein
A
true
5
Q
true or false: inductive reasoning applies general principles to predict specific results
A
false
6
Q
true or false: the pH of a solution is a measure of the
-log[H+]
A
true
7
Q
true or false: a fatty acid chain that lacks double bonded carbons, is considered a saturated fatty acid
A
true
8
Q
true or false: chaperone proteins help newly synthesized proteins fold correctly into functional structures
A
true
9
Q
true or false: in general, fruits and vegetables contain more saturated fats than meats
A
false
10
Q
true or false: life a dynamic process that is constantly in flux, thus living things exist in a non equilibrium state
A
true
11
Q
the first life form from which all life forms on Earth are believed to be derived from, first appeared __ billion years ago (BYA)
A
3.5
12
Q
how are the tails and heads of membrane phospholipids oriented in their environment?
A
the hydrophobic tails are oriented towards each other and the hydrophilic heads are oriented towards the extracellular fluid and the intracellular fluid
13
Q
which of these carbohydrates is not a six carbon sugar?
A
ribose
14
Q
which types of monomers make up proteins
A
amino acids
15
Q
in which type of macromolecule found in living systems would you expect to find a sulfhydryl group (-S-H)?
A
protein
16
Q
based on the “Hypothesis-driven science” example on scientific investigations given in class (crying 3 month old baby), how would you describe “baby is hungry” on the flow chart?
A
hypothesis
17
Q
out of the 12 elements that make up most living things, which four elements make up 96.4% of the human body?
A
oxygen, nitrogen, hydrogen, carbon (COHN)
18
Q
proteins are important to biological systems because of their function in
A
cell movement, cell structure, and enzyme catalysis
19
Q
a substance that has a high concentration of hydrogen ions ( >10^-7)
A
is called a acid
20
Q
in his book “On the Origin of Species by Means of Natural Selection” Charles Darwin based his theory of Natural Selection on observations that were made on adaptive differences saw in which animal on the Galapagos Islands
A
cactus finch
21
Q
what is the name given to the electrons found in the outer most rings of an atom?
A
valence electrons
22
Q
which of the following is NOT a property of the elements most commonly found in living organisms
A
the elements possess eight electrons in their outer energy level
23
Q
of the four structures associated with protein, which structure would not be effected by denaturing the protein
A
primary structure
24
Q
biologists have divided all living things into three domains, Bacteria, Archaea, and Eukarya. The Eukarya are further subdivided into four kingdoms of Protista, fungi, Animalia, and plantae. within these domains, which of these have cells that are ONLY composed of single cell organisms with little internal structure
A
bacteria
25
a atom with a net positive charge must have __
more protons than electrons
26
if the atomic number of nitrogen (N) is 7, how many electrons would be needed to be shared by covalent bonds to fill the outer shell of the Nitrogen atom
three
27
How is the process of natural selection different from that of artificial selection
artificial selection is a result of human intervention
28
which of these types for chemical bond are correctly organized from the strongest to the weakest
covalent, ionic, hydrogen
29
what was the contribution to science of Pasteur's classic experiment
disproved spontaneous generation hypothesis
30
which of the following is not a disaccharide
fructose
31
which hierarchical group contains the most diverse group of organisms?
community
32
RNA is a form of __ composed of __
nucleic acid; phosphate, 5-carbon sugar, and nitrogen base
33
which of these biological categories is not part of the domain eukarya?
archaea
34
the organization of living systems is __
hierarchical with cells at the base and the biosphere at the top
35
if I knew that I had a sample of a nucleic acid, how would I be able to determine, if the sample was only composed of DNA. I would know by the absence of __
uracil
36
a scientific theory states __
a statement of how the world works that is supported by experimental data
37
a solution that has a change of 4 pH units indicates what fold change in the [H+] of the solution
10,000 X
38
if you shake a bottle of oil and vinegar then let it sit, it will separate into 2 phases because __
non polar oil is not soluble in water
39
which part of a nucleic acid is the variable portion that defines it as Adenine, Cytosine, Guanine, Thymine?
the nitrogen base
40
when water molecules stick to the other polar molecules (other than water) by hydrogen bonding, that is called __
adhesion
41
what is the chronological order of the scientific method?
observation, question, hypothesis, experiment, data, prediction
42
if the basic (neutral) structure of a carbon-12 atom is 6 protons, 6 neutrons, 6 electrons, what is the structure of the isotope carbon-13?
6 protons, 7 neutrons, 6 electrons
43
an element is said to be radioactive when the number of __ is greater than the other subatomic particles in the atom
neutrons
44
the mass of an atom is determined by its __ and __
neutron; proton
45
phospholipids that form membranes in cells are composed of
phosphate group, glycerol, and fatty acid
46
plant cells store energy in the form of __, and animal cells store energy in the form of __
starch; glycogen
47
when we talk about "Sodium chloride dissolving in water by the formation of hydration cells", what property of water is this related to?
solubility
48
of the 90 naturally occurring elements on Earth, how many of them are actually found in living systems in more than trace amounts?
12 elements
49
which carbohydrate would you find as part of a molecule of RNA?
none of these
50
true or false: coupled transport uses the concentration gradient established by active transport
true
51
true or false: bacterial cells that can alter the composition of the fatty acids in their membrane phospholipids would increase their unsaturated fatty acids in a cold climate
true
52
true or false: the gram stain is determined by the composition of the bacterial phospholipid bilayer
false
53
true or false: pinocytosis is not a mechanism for brining material into the cell
false
54
true or false: Robert Koch studied anthrax; proposed four postulates to prove a causal relationship between a microorganism and a disease
true
55
true or false: bacterial transformation and transduction the same process
false
56
true or false: osmosis is the diffusion of water across a membrane in response to the concentration of one or more of the cells
false
57
true or false: Robert Hooke first described "cells"
true
58
true or false: small cells have a greater surface-area-to-volume ratio than large cells
true
59
true or false: fusion of mouse and human cells was a classic experiment which established that cell membrane was not fluid
false
60
for the process of diffusion to occur, molecules must
move from areas of high concentration to areas of lesser concentration until an equilibrium is reached
61
dental plaque (a biofilm), a first stage in tooth decay, consists of
bacteria surrounded by a polysaccharide matrix
62
cell division in prokaryotic cells occurs by a process called
binary fission
63
the part of a membrane protein that extends through the phospholipid bilayer is primarily composed of amino acids that are
non-polar
64
mitochondria and chloroplasts are the other organelles besides the nucleus that contain:
DNA
65
when bacteria are exposed to nutrient-poor conditions, they form thick-walled structures that contain the chromosome and a small amount of cytoplasm. These structures are called
endospores
66
streptomycin is an antibiotic that interferes with the function of the 30S subunit of the prokaryotic ribosome. What is the consequence of treating a bacteria with streptomycin?
impaired protein synthesis
67
which type of proteins is embedded in the cell membrane in both active transport and facilitated transport?
carrier
68
in bacteria, fungi, and plants, the high internal pressure generated by osmosis is counteracted by the mechanical strength of their
cell walls
69
the protein sorting pathway involves the following organelles/compartments in order:
RER, transport vesicle, Golgi, final destination
70
Phil has chronic ulcers, he has been taking acid blockers and drinking vast amounts of liquid antacids. These help relieve the symptoms but he still suffers from ulcers. What would be the best course of action to treat the source of his ulcers?
taking a course of antibiotics
71
which of the following statements about sexually transmitted diseases (STDs) is false?
because chlamydia has both bacterial and viral characteristics, it cannot be treated with antibiotics
72
which of the following does NOT contribute to the secretive permeability of a biological membrane?
hydrogen bond formation between water and phosphate groups
73
the plasma membrane is said to be a fluid-mosaic of phospholipids because it contains __
a mosaic of proteins suspended within a phospholipid bilayer
74
the evolutionary process that created chloroplasts and mitochondria is
endosymbiosis
75
which of these terms describes the recipient cell following the transfer of the F plasmid with integration into the host chromosome?
Hfr+ cell
76
if two solutions have unequal concentrations of a solute, the solution with the lower concentration is called
hypotonic
77
flattened sacs of internal membranes associated with photosynthesis are called
thylakoids
78
using the picture below: which organelle contains the hydrolytic proteins that breaks down molecules
lysosome
79
current classification of prokaryotes is based on
sequencing of proteins, DNA, and RNA
80
which type of cell membrane protein hold cells together to form tissues?
junction proteins
81
if the label on a slide reads gram-positive bacillus, what would a student expect to see?
purple rod shaped cells
82
the process often referred to as "bulk transport" into the cell is referred to as __
endocytosis
83
plasmodesmata in plants and gap junctions in animals are functionally similar in that
they form channels between cells that allow diffusion of small molecules
84
the peptidoglycan of bacterial cell walls contains a carbohydrate matrix linked together by short chains of
amino acids
85
microfilaments such as actin, microtubules, and the intermediate filaments form the cell-supporting structure called the
cytoskeleton
86
a scientist performs an experiment in which they create an artificial cell with a selectively permeable membrane through which only water can pass. They inject a 5M solution of glucose into the cell and then place the cell into a beaker containing 5M glucose. What effect do you expect to observe?
no net change in cell weight
87
which of these is not a common shape associated with bacteria?
none, they all are
88
Schleiden and Schwann stated the "cell theory", which in its modern form says
all organisms are composed of one or more cells, all cells are the smallest living things and all cells arise by division of other cells
89
based on the data, which gene is closest to gene 1?
gene 2
90
why is chlamydia much more common than syphilis?
many chlamydia infections are asymptomatic
91
which of these bulk transport mechanisms is used in animals to secrete hormones, neurotransmitters, or digestive enzymes?
exocytosis
92
which of the following is an INCORRECT match?
smooth ER - storage of water
93
in a single sodium-potassium pump cycle, ATP is used with the result that
3 sodium ions leave and 2 potassium ions enter
94
which of these bacterial diseases causes an acute infection of the respiratory system in humans?
mycobacterium tuberculosis
95
when bacteria are used to remove pollutants from water, air, and soil, the term used to describe this process is
bioremediation
96
how can freeze-fracture be used to determine the orientation of a protein in a membrane?
freeze-fracture allows a cell to be cleaved in between the lipid bilayer, splitting the plasma membrane into two layers
97
organelles that breakdown hydrogen peroxide into water and oxygen are
peroxisomes
98
cell membrane proteins that actively transport molecules and ions against a concentration gradient (from areas of low to high concentrations) are
transport proteins
99
a cell biologist has developed a new drug that blocks a vesicle transport at the cis face of the Golgi apparatus. What will this drug prevent from happening inside a cell?
the movement of lipids and proteins from the endoplasmic reticulum to the Golgi apparatus
100
true or false: the Krebs cycle is a catabolic pathway, while the Calvin cycle is an anabolic pathway
true
101
true or false: cactus and pineapple are examples of plants that carry out CAM photosynthesis
true
102
true or false: a solenoid is a unit of light energy from the sun
false
103
true or false: oxidation and reduction reactions are chemical processes that result in a gain or loss of electrons
true
104
true or false: in an enzyme-catalyzed reaction, the reactant is called the product
false
105
true or false: photorespiration occurs when excessive heat causes stoma to close and traps gasses in the leaves which causes RuBP binds to O2 instead of CO2
true
106
consider the signaling pathway: epinephrine > G coupled Protein Receptor > G protein > Adenylyl cyclase > cAMP > protein kinase A. Identify the second messenger
cAMP
107
the receptors for steroid hormones and peptide hormones are fundamentally different because
peptides are hydrophilic and steroids are hydrophobic
108
the law of thermodynamics that states that energy cannot be created nor destroyed is
the first law of thermodynamics
109
the energy needed to destabilize existing chemical bonds and stand a chemical reaction is called
activation energy
110
pyruvate oxidation in eukaryotic cells occurs in the __
mitochondria
111
why is the energy generated from the catabolism of sugars and other macromolecules ultimately harnessed to generate ATP?
ATP can be used by cells to drive endergonic reactions
112
what stage of cellular respiration can occur in human cells with or without oxygen present?
glycolysis
113
which of these statements describes endocrine signaling?
hormones released from a cell travel through circulatory system to affect other cells throughout the body
114
during the day, where in the chloroplast would you find the highest concentration of protons?
in the stroma
115
interaction of components __ and __ initiates the process of signal transduction, which converts the information in the signal into a cellular response
receptor; ligand
116
the Krebs cycle occurs in the mitochondria. there are nine biochemical reactions involved in the Krebs cycle, and they are highly ordered. Select the correct order
acetyl-CoA joins the Krebs cycle and unites with oxaloacetate -> forming citrate -> which forms a-ketoglutarate -> which forms succinyl-CoA -> which forms succinate -> which forms fumarate -> which forms malate -> which forms oxaloacetate
117
a drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme, it prevents substrate binding. This drug would be considered a(n)
competitive inhibitor
118
organisms that can manufacture their own chemical energy are called __
autotrophs
119
when an atom or molecule gains or more electrons, it is said to be
reduced
120
energy is defined as
the capacity to do work
121
all of these are "electron carriers" except
ATP
122
all of these are phases of the light-independent Calvin cycle, except one __
oxidation of water
123
the ultimate source of energy for humans comes from what source?
the sun
124
the wavelengths of light that are most effective for photosynthesis are __
red, blue, and violet
125
what is the correct order of steps in the light dependent reactions of photosynthesis?
photosystem II > electron transport system > photosystem I > electron transport system > ATP synthase
126
which type of receptor-ligand binding leads to activation of glycogen synthase?
insulin receptor
127
the production of ATP by chemiosmosis occurs in mitochondria (during respiration), and chloroplasts (during photosynthesis) when there is a imbalance of __
[H+]
128
hydrophobic-nonpolar ligands, such as steroids, cross the membranes of all cells, but effect only target cells because
intracellular receptors are present only in target cells
129
binding of a signaling molecule to which type of receptor leads directly to a change in the distribution of ions on opposite sides of a membrane
ligand-gated ion channel
130
one way to generate acetyl-CoA is to convert pyruvate into acetyl-CoA by stripping off a CO2
decarboxylation
131
based on the graph, what are the optimal temperatures for the human enzyme and hot springs prokaryote enzyme?
the optimal temperature for the human enzyme is 40ºC. The optimal temperature for the hot springs prokaryote enzyme is 72ºC
132
in the process of cell signaling, scaffolding proteins organize the components of a kinase cascade into a single protein complex, which gives the advantage of efficiency, to the complex, however it does have a disadvantage in __
reducing the amplification effect
133
a particular chemical reaction is exergonic. What can you say about the relationship between the reactants and the products in this exergonic reaction?
the reactants have more free energy than the products
134
when oxygen is unavailable during heavy exercise, what process do muscle cells use for energy generation?
glycolysis coupled with lactate fermentation
135
these three amino acids have -OH as R-groups that can be phosphorylated
tyrosine, serine, theronine
136
what is an end-product of glycolysis?
pyruvate
137
what aspect of cellular respiration occurs in the cytoplasm in eukaryotic cells?
glycolysis
138
this scientist believed the mass of plants came from not soil, but water
Jan Baptista van Helmont
139
which pair are examples of second messengers?
cAMP, calcium ions
140
C4 pants initially fix carbon by
incorporating CO2 into oxaloacetate, which is converted into malate
141
while standing at the top of the stairs, you have a PE of 40 joules. If you walk all the way down the stairs, what would your PE be at the bottom of the stairs?
0 joules
142
glucose is not our only food source, nor the only one we can utilize in our bodies to generate energy. Other primary sources of energy include other sugars, proteins, and fats. What metabolic intermediate are fats primarily converted into?
acetyl-CoA
143
what are the products of one turn of the Krebs cycle?
2 CO2, 3 NADH, 1 FADH2, 1 ATP
144
you return home to find that your baby brother has scattered his toy trains and trucks all over the floor of your room. As you begin to pick up the toys and put them away, you realize that even though he is just a baby, he has clearly mastered:
the second law of thermodynamics
145
true or false: Prokaryotic conjugation which results in the transfer and insertion of the F plasmid into a recipient cell'schromosome leads to the formation an F+ cell.
false
146
true or false: Unsaturated fatty acids make cell membranes more fluid than saturated fatty acids.
true
147
Plasmids are distinguished from bacterial chromosomes in that
plasmids have few genes, bacterial chromosomes have many genes.
148
While water continually orients phospholipids into a lipid bilayer, it does not fix the lipids permanently into position. Thus, the bilayer is considered to be ________.
fluid
149
The lipid layer that forms the foundation of cell membranes is primarily composed of molecules called ________.
phospholipids
150
A cytologist is examining a tissue under an electron microscope. He notices that the endoplasmic reticulum of each cell is extremely rough in appearance and he knows that the rough appearance is because of the ribosomes embedded there. He asks why there areso many ribosomes. You respond,
"This tissue exports proteins to other areas of the body."
151
The semi-fluid matrix that surrounds organelles in a cell is called the:
cytoplasm
152
Which of these is not a mechanism of vertical gene transfer in prokaryotes?
none
153
Prokaryotes undergo a process that produces cells that are identical. This process is called
binary fission
154
Which of these prokaryotic organsisms is called the "Silent STD"?
Chlamydia trachomatis
155
If the label on a slide reads Gram-positive bacillus, what would a students expect to see?
Purple rod shaped cells
156
Osmosis is the diffusion of water across a membrane in response to the concentration of one or more of the ___.
solutes
157
In a single sodium-potassium pump cycle, ATP is used with the result that
3 sodium ions leave and 2 potassium ions enter.
158
The type of movement that is specific and requires carrier molecules and energy is
active transport
159
Some prokaryotes attach to other substrates by hairlike outgrowths, which are shorter than flagella. These are called
pili
160
Which of the following enables a cell to pick up and concentrate a specific type of molecule?
receptor-mediated endocytosis
161
If left untreated, syphilis infections go through four stages. The first stage is a sore calleda chancre. The signs of the second stage are
rash, sore throat, and sores in the mouth
162
Organelles that breakdown hydrogen peroxide into water and oxygen are:
peroxisomes.
163
The part of a membrane protein that extends through the phospholipid bilayer is primarily composed of amino acids that are
non-polar.
164
Small cells function more effectively, because as cells become larger their surface area to volume ratio:
decreases
165
On the outer surface of the plasma membrane there are marker molecules that identify the cell type. Often these molecules are
carbohydrate chains.
166
Current classification of prokaryotes is based on
sequencing of proteins, DNA, and RNA.
167
The movement of substances to regions of lower concentration is called
diffusion
168
true or false: Most competitive inhibitors bind to allosteric sites on an enzyme.
false
169
true or false: Exergonic reactions occur spontaneously after the energy of activation is achieved
true
170
true or false: Coupled transport uses the concentration gradient established by active transport.
true
171
Most enzymes are composed of ____
Proteins
172
In eukaryotes, photosynthesis takes place inside the _______
chloroplasts
173
The light-independent reactions of photosynthesis are those that
convert CO2 into reduced molecules (sugars).
174
the "Chief currency" that all cells use for energy is _______.
ATP
175
The discovery of ribozymes meant that
RNAs can act as enzymes.
176
What happens to the oxygen that is used in cellular respiration?
It is reduced to form water
177
Visible light has a wavelength range of
400-740 nanometers.
178
Which of these statements are true of ATP ?
ATP hydrolysis drives endergonic reactions
179
If the label on a slide reads Gram-positive bacillus, what would a students expect to see?
Purple rod shaped cells
180
What chemical property characterizes the interior of the phospholipid bilayer?
It is hydrophobic
181
Organisms that can manufacture their own chemical energy are called _____.
autotrophs
182
What color of light is least strongly absorbed by chlorophyll?
green
183
For photosynthesis in green plants, the electron donor for the light dependent reaction is
water.
184
In aerobic respiration, chemiosmotic generation of ATP is driven by:
a difference in H+ concentration on the two sides of the inner mitochondrialmembrane.
185
NADPH is made by
the passing of electrons from photosystem I to an electron transport chain.
186
What is activation energy?
The energy required to initiate a chemical reaction.
187
An endergonic reaction has the following properties
+∆G and the reaction is not spontaneous
188
What oxidizing agent is used to temporarily store high energy electrons harvested fromglucose molecules in a series of gradual steps in the cytoplasm?
NAD+
189
true or false: Proto-oncogenes function by preventing cells from dividing uncontrollably.
false
190
Nucleotides have a phosphate group attached at the ________ carbon atom of the sugar.
5'
191
In your research, you have discovered that Protein X is often ubiquitinated in people with a certain disease. What would you predict about levels of Protein X in these patients?
Levels of Protein X will be low due to degradation in the proteasome.
192
Certain proteins can bind to specific DNA regulatory sequences by entering
the major groove of the DNA and reading the nucleotide base pairs.
193
The enzyme dicer chops dsRNA molecules into small pieces of
miRNA and siRNA.
194
You are studying regulation of a prokaryotic operon. Experiments show that expression of the operon is increased when levels of biosynthetic product from that pathway are low. Based on this information, what is a likely mode of regulation?
The product binds a repressor, allowing it to bind the operator.
195
Information obtained by Franklin from X-ray crystallography on DNA suggested that itis shaped like a
helix.
196
Viruses that attack bacteria are called
phages
197
You decide to repeat the Meselson-Stahl experiment, except this time you plan to grow the E. coli cells on light 14N medium for many generations and then transfer them to heavy 15N medium and allow them to grow for 2 additional generations (2 rounds of DNA replication). If the conservative model of DNA replication was correct, what is the expected distribution of DNA in the density gradient after two rounds of replication?
One band of light density and one band of heavy density.
198
Single-stranded ends generated by the same restriction enzyme are complementary to each other. They can be joined together,
even when the source of the DNA is different.
199
You are studying the effects of specific transcription factors on the activation of gene expression. You notice that one particular transcription factor binds far away from the promoter of its target gene. What can explain this?
DNA looping brings the transcription factor closer to the promoter and initiates gene transcription.
200
Which statement about the Hershey-Chase experiment is false?
The virus-infected bacteria contained radioactive sulfur.
201
If you were able to look very closely at a portion of DNA and find methylated histones, you would
be looking at a region of inactive chromatin.
202
Because the two strands of a DNA molecule are ________ to each other, either one can be used as a template to reconstruct the other.
complementary
203
If a strain of bacteria had a mutation that blocked expression of the lac repressor, what would you expect as a result?
The mutant strain would waste energy producing enzymes in the absence oflactose.
204
BamHI is a Type II restriction enzyme that recognizes the sequence 5' G*GATCC 3', and cuts between the two Gs, leaving a 5' overhang. If you were to digest DNA withBamHI, what would be the sequence of the overhanging sticky ends of the two strands?
5' GATC 3' and 5' GATC 3'
205
The method of DNA replication, where each original strand is used as a template to build a new strand, is called the
semiconservative method.
206
You are working to identify enhancer regions of a particular gene. The best place to look is
primarily upstream of the promoter, possibly some distance away.
207
You have been asked to design a synthetic DNA motif, able to bind transcriptional regulatory proteins. The location on this motif that you will design for protein binding is the
major groove of the DNA double helix.
208
The PCR technique requires a DNA polymerase from an organism that can endure high heat, such as Thermus aquaticus. What step of the protocol makes the heat-stability most necessary?
Denaturation
209
In vertebrates, DNA methylation-the addition of a methyl group to DNA nucleotides-ensures that
once a gene is turned off, it will remain off.
210
After attaching to a bacterial cell, a bacteriophage typically
injects DNA into the cell.
211
When E. coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the
trp operon.
212
The observable expression of the genes present in an organism is called its
phenotype.
213
________ are a type of internal signal molecule used in controlling the cell cycle.
Kinases
214
A tumor suppressor gene undergoes a mutation that causes it to lose its normal function. What would be the most likely result of this mutation?
The cell no longer responds to signals that cause it to stop dividing or undergoapoptosis.
215
Which of the following statements is correct?
Meiosis involves 2 divisions and produces 4 non-identical daughter nuclei.
216
When during the cell cycle are chromosomes visible?
during Mitosis
217
Barr bodies —
All of the above
218
What structure is formed by two sister chromatids being held together by a centromere?
chromosome
219
Individuals that have 2 alleles for most gene loci are best described as
diploid
220
Let P = purple flowers and p = white, and T = tall plants and t = dwarf. What are the genotypes of the gametes that are produced by a plant that is heterozygous for both traits?
PT, Pt, pT, and pt
221
If an individual allele has more than one effect on the phenotype, this is called
pleiotropy.
222
Irene knows her blood type is A, but William does not know his blood type. However, William knows that his mother and father both had blood type B. Irene and William's first child is a boy with type O blood. Based on this information, William's blood type could be
either B or O
223
In humans, the sickle-cell trait is caused by a single defective allele, but sickle-cell disease only occurs in individuals that are homozygous for the sickle-cell allele. A man and woman each carry the trait, but do not have sickle-cell disease. What is the probability that their first two children will both have sickle-cell disease?
1/16
224
Cold weather can change what aspect of a Himalayan rabbit?
phenotype
225
In Mendel's experiments on seed color in pea plants, when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant, what was the approximate phenotypic ratio among the F2 generation?
3 yellow: 1 green
226
Chromosomes that occur in pairs and code for the same traits are called _____ chromosomes; these do not include the _____ chromosomes which code for gender.
homologous: sex
227
An individual with the karyotype 48, XYYY would have how many Barr bodies?
0
228
The failure of sister chromatids to separate during meiosis is called
nondisjunction.
229
Amniocentesis is a —
medical procedure permitting prenatal diagnosis of many genetic disorders.
230
If a short sequence of DNA is 5' AATTGCCGT 3', its complement is
3' TTAACGGCA 5'.
231
If 14% of the nucleotides from a DNA molecule contain the base T, what percent will contain the base G?
36%
232
During DNA replication, which enzyme removes the RNA primers and then fills in the gap?
DNA pol I
233
true or false: The monosaccharide galactose (C6H12O6 ) is a stereoisomer of glucose
true
234
true or false: Monomers of all carbohydrates are composed of three chemical groups, a triphosphate, nitrogenous base, and 5-carbon sugar.
false
235
true or false: Living systems exist in an equilibrium state.
false
236
The "Chief currency" that all cells use for energy is ___.
ATP
237
The property of water that stabilizes the internal temperature of an organism against changes in the external environment, is best describes as ____.
High specific heat
238
This property of water allows a plants leaves to pull water up from the roots, and seeds to swell and germinate.
cohesion and adhesion
239
Which hierachical organization of living systems do tissues belong?
organismal level
240
A mutation that effects a single amino acid change within the polypeptide sequence of a protein, alters_____.
all of these
241
Which of these is not a lipid?
glucose
242
Plant cells store energy from glucose in the form of _______, and animal cells store energy from glucose in the form of ____.
starch; glycogen
243
The molecules of DNA are most important to biological systems because _____
they encode the information necessary for making a new individual.
244
Which of the following is not a property of elements most commonly found in living organisms?
The elements posess eight electrons in their outer energy level.
245
Which structure of a protein would not be affected by heat denaturation?
Primary structure
246
Which of the solutions listed below would you expect to be described as a weak base?
sea water
247
A fatty acid chain that lacks double bonded carbons, is considered a _____ fatty acid.
saturated
248
Out of the 12 elements that make up most living things, which four elements make up 96.4% of the human body?
Oxygen, Nitrogen, Hydrogen, Carbon
249
How is the process of natural selection different from artificial selection?
Artifical selection selection is a result of human intervention.
250
Covalent bonds arise from ____.
shared valence electrons
251
A DNA molecule containing 25% thymine would contain how much cytosine?
25%
252
What is the significance of Pasteur's experiment to test the germ hypothesis?
It demonstrated that cells can only arise from other cells.
253
Evolutionary conservation occurs when a characteristic is
important to the life of an organism.
254
The isotopes carbon-12 and carbon-14 differ in
the number of neutrons
255
Using the periodic table , which of the following atoms would you predict should form a positively charged ion (cation)?
Potassium (K)
256
A molecule with polar covalent bonds would
be soluble in water.
257
What aspect of triglyceride structure accounts for their insolubility in water?
The non polar C-H bonds in fatty acids
258
which of the following statements is NOT part of the cell theory?
eukaryotic cells have evolved from prokaryotic cells
259
all cells have all of the following except
a) plasma membrane
b) genetic material
c) cytoplasm
d) cell wall
cell wall
260
eukaryotic cells are more complex than prokaryotic cells. which of the following are found only in a eukaryotic cell?a) cell wall
b) plasma membrane
c) ER
d) ribosomes
ER
261
which of the following are differences between bacteria and archaea?
the molecular architecture of their cell walls
262
the cytoskeleton includes
intermediate filaments made of twisted fibers of vimentin and keratin
263
the smooth ER is
the site of lipid and membrane synthesis
264
plasmodesmata in plants and gap junctions in animals are functionally similar in that
they form channels between cells that allow diffusion of small molecules
265
the most important factor that limits the size of a cells is the
surface area-to-volume ratio of the cell
266
all eukaryotic cells possess each of the following except
a) mitochondria
b) cell wall
c) cytoskeleton
d) nucleus
cell wall
267
adherens junctions, which contain cadherin, are found in all animals. Given this, which of the following predictions is most likely?
cadherins would be found in the ancestor to all animals
268
different motor proteins like kinesin and myosin are similar in that they can
use e from ATP to produce movement
269
the protein sorting pathway involves the following organelles/compartments in order
RER, transport vesicle, Golgi, final destination
270
chloroplasts and mitochondria have many common features bc both
arose by endosymbiosis
271
eukaryotic cells are composed of 3 types of cytoskeletal filaments. How are these 3 filaments similar?
they contribute to the shape of the cell
272
the fluid mosaic model of the membrane describes the membrane as
made up of proteins and lipids that can freely move
273
what chemical property characterizes the interior of the phospholipid bilayer
it is hydrophobic
274
the transmembrane domain of an integral membrane protein
is composed of hydrophobic amino acids, often forms an a-helical structure, can cross the membrane multiple times
275
the specific function of a membrane within a cell is determined by the
type and number of membrane proteins
276
the movement of water across a membrane is dependent on
the solute concentration
277
if a cell is in an isotonic environment, then
osmosis still occurs, but there is no net gain or loss of cell volume
278
which of the following is NOT a mechanism for bringing material into a cell
exocytosis
279
a bacteria cell that can alter the composition of saturated and unsaturated fatty acids in its membrane lipids is adapted to a cold environment. If this cell is shifted to a warmer environment, it will react by
increasing the degree of saturated fatty acids in its membrane
280
what variable(s) influence(s) whether a non polar molecule can move across a membrane by passive diffusion?
the difference in conc of the molecule across the membrane
281
which of the following does NOT contribute to the selective permeability of a biological membrane?
hydrogen bond formation between water and phosphate groups
282
how are active transport and coupled transport related?
coupled transport uses the conc gradient established by active transport
283
a cell can use the process of facilitated diffusion to
move ions or large polar molecules from a region of high conc to a region of low conc
284
which of the following would be an example of a biomarker?
a hydrocarbon found in an ancient rock layer
285
a cell that can use e from the sun, and CO2 as a carbon source is a
photoautotroph
286
gram positive (+) and gram (-) bacteria are characterized by differences in
the cell wall: gram + have a thick layer of peptidoglycan and gram - have an outer membrane
287
which of the following characteristics is unique to the archaea?
ether-linked phosolipids
288
the horizontal transfer of DNA using a plasmid is an example of
conjugation
289
the disease tuberculosis is
caused by a bacterial pathogen
290
prokaryotes participate in the global cycling of
carbon and nitrogen
291
which of the following is typically NOT associated with a prokaryote?
multiple, linear chromosomes
292
the mechanisms of DNA exchange in prokaryotes share the feature of
horizontal transfer of info
293
the cell wall in both gram-positive and gram-negative cells is
a target for antibiotics that affect peptidoglycan synthesis
294
the three domains of life
consist of three different basic cell types
295
ulcers and tooth decay do not appear related, but in fact both
can be due to bacterial infection
296
bacteria lack independent internal membrane systems, but are able to perform psyn and resp, both of which use membranes. they are able to perform these functions bc
invaginations of the plasma membrane can provide an internal membrane surface
297
plants cannot fix nitrogen, yet some plants do NOT need nitrogen from the soil. This is because...
of a symbiotic association with a bacterium that can fix nitrogen
298
An autotroph is an organism that
does both a and b
a. extracts energy from organic sources.
b. converts energy from sunlight into chemical energy
299
Which of the following processes is (are) required for the complete oxidation of glucose?
all of the choices are correct
a. The Krebs cycle
b. Glycolysis
c. Pyruvate oxidation
300
Which of the following is NOT a product of glycolysis?
CO2
301
Glycolysis produces ATP by
substrate-level phosphorylation
302
What is the role of NAD+ in the process of cellular respiration?
It functions as an electron carrier
303
The reactions of the Krebs cycle occur in the
matrix of the mitochondria
304
the electrons carried by NADH and FADH2 can be
moved between proteins in the inner membrane of
| the mitochondrion
305
which of the following is NOT a true statement regarding cellular respiration?
Electrons have a higher potential energy at the end
| of the process.
306
The direct source of energy for the ATP produced by ATP synthase comes from
a proton gradient
307
Anaerobic respiration
yields less energy than aerobic respiration because other final electron acceptors have lower affinity for electrons than O2
308
what is the importance of fermentation to cellular metabolism?
It oxidizes NADH to NAD+ in the absence of O2
309
The link between electron transport and ATP synthesis
is a proton gradient.
310
a chemical agent that makes holes in the inner membrane of the mitochondria would
stop ATP synthesis.
311
Yeast cells that have mutations in genes that encode enzymes in glycosides can still grow on glycerol. They are able to utilize glycerol because it
can feed into the Krebs cycle and generate ATP via e- transport and chemiosmosis.
312
the light-dependent rxns of psyn are responsible for the production of
ATP and NADPH
313
Which region of a chloroplast is associated with the capture of light energy?
Thylakoid membrane
314
The colors of light that are most effective for photosynthesis are
red, blue, and violet
315
During noncyclic photosynthesis, photosystem I functions to ___________, and photosystem II functions to _____________
reduce NADP+; oxidize H2O
316
How is a reaction center pigment in a photosystem different from a pigment in the antenna complex?
The reaction center pigment loses an electron when it absorbs light energy.
317
The ATP and NADPH from the light reactions are used
during the reactions of the Calvin cycle to produce glucose.
318
The carbon fixation reaction converts
inorganic carbon into an organic acid.
319
C4 plants initially fix carbon by
incorporating CO2 into oxaloacetate, which is converted to malate.
320
The overall flow of electrons in the light reactions is from
H2O to NADPH.
321
If you could measure pH within a chloroplast, where would it be lowest?
In the lumen of the thylakoid
322
The excited electron from photosystem I
Both a and c are correct.
a. can be returned to the reaction center to generate ATP by cyclic photophosphorylation.
c. is replaced by an electron from photosystem II.
323
If the Calvin cycle runs through six turns
enough carbon will be fixed to make one glucose, but they will not all be in the same molecule.
324
Which of the following are similarities between the structure and function of mitochondria and chloroplasts?
Both a and c are correct.
a. They both create internal proton gradients by electron transport.
reactions.
c. They both have a double membrane system.
325
Given that the C4 pathway gets around the problems of photorespiration, why don’t all plants use it?
It also has an energetic cost.
326
if the thylakoid membrane became leaky to ions, what would you predict to be the result on the light reactions?
It would stop ATP production.
327
the overall process of photosynthesis
results in the reduction of CO2 and the oxidation of H2O.
328
the function of a __ is to add phosphates to proteins, whereas a __ functions to remove the phosphates
protein kinase, protein phosphatase
329
which of the following receptor types is NOT a membrane receptor
a. channel-like receptor
b. enzymatic receptor
c. G protein-coupled receptor
d. steroid hormone receptors
steroid hormone receptors
330
how does the function of an intracellular receptor differ from that of a membrane receptor?
the intracellular receptor binds DNA
331
signaling through receptor tyrosine kinases often
leads to the activation of a cascade of kinase enzymes
332
what is the function of Ras during tyrosine kinase cell signaling?
it links the receptor protein to the MAP kinase pathway
333
which of the following best describes the immediate effect of ligand binding to a G protein-coupled receptor?
the G protein trimer releases a GDP and binds a GTP
334
the action of steroid hormones is often longer-lived than that of peptide hormones. this is because they
they turn on gene expression to produce proteins that persist in the cell
335
the ion Ca2+ can act as a second messenger because it is
normally at a low level in the cytoplasm
336
different receptors can have the same effect on a cell. one reason for this is that
signal transduction pathways intersect- the same pathway can be stimulated by different receptors
337
in comparing small G proteins like Ras and GPCR proteins, we can say that
both proteins have intrinsic GTPase activity that stops signaling & both proteins are active bound to GTP
338
the same signal can have different effects in different cells because there
a. are different receptor subtypes that initiate different signal transduction pathways.
b. may be different coactivators in different cells.
c. may be different target proteins in different cells’ signal
transduction pathways.
339
The receptors for steroid hormones and peptide hormones are fundamentally different because
peptides are hydrophilic and steroids are hydrophobic
340
paracrine signaling is characterized by
secreted by neighboring cells
341
signal transduction pathways
include the intracellular events stimulated by an extracellular signal
342
a covalent bond between 2 atoms represents what kind of energy?
potential energy
343
during a redox rxn the molecule that gains an electron has been
reduced and now has a higher energy level
344
an endergonic rxn has the following properties
+∆G and the rxn is not spontaneous
345
a spontaneous rxn is one in which
the reactants have a higher free energy than the products
346
what is activation energy?
the energy required to initiate a chemical rxn
347
which of the following is not a property of a catalyst?
a catalyst lowers the free energy of the reactants
348
where is the energy stored in a molecule of ATP?
in the bonds connecting the two terminal phosphate groups
349
cells use ATP to drive endergonic rxns because
energy released by ATP hydrolysis makes ∆G for coupled rxns more negative
350
which of the following statements is not true about enzymes?
enzymes make ∆G for a rxn more negative
351
ATP hydrolysis has a ∆G of -7.4 kcal/mol. Can an endergonic rxn with a ∆G of 12 kcal/mol be "driven" by ATP hydrolysis?
no, the overall ∆G is still positive
352
an online auction site offers a perpetual-motion machine. You decide not to bid on this because
the second law says that energy loss due to entropy will not allow for perpetual motion
353
enzymes have similar responses to both changes in temperature and pH. The effect of both is on the
three-dimensional shape of the enzyme
354
feedback inhibition is an efficient way to control a metabolic pathway because the
first enzyme is the pathway inhibited by the end-product of the pathway
355
Binary fission in prokaryotes does not require the
assembly of the nuclear envelope
356
Chromatin is composed of
DNA and protein
357
What is a nucleosome?
a region of DNA wound around histone proteins
358
what is the role of cohesin proteins in cell division?
they hold the DNA of the sister chromatids together
359
the kinetochore is a structure that functions to
connect the centromere to microtubules
360
separation of the sister chromatids occurs during
anaphase
361
why is cytokinesis an important part of cell division?
it is responsible for the proper separation of the cytoplasmic contents
362
what steps in the cell cycle represent irreversible commitments?
both b and c
b. The G1/S checkpoint
c. Anaphase
363
Cyclin-dependent kinases(Cdks) are regulated by
the periodic destruction of cyclins
364
The bacterial SMC proteins, eukaryotic cohesin proteins, and condensin proteins share a similar structure. Functionally they all
interact with DNA to compact or hold strands together
365
Genetically, proto-oncogenes act in a dominant fashion. this is because
they act in a gain-of-function fashion to turn on the cell cycle
366
The metaphase to anaphase transition involves
loss of cohesion between sister chromatids
367
the main difference between bacterial cell division and eukaryotic cell division is that
none of the above is correct
368
in animal cells, cytokinesis is accomplished by a contractile ring containing actin. The related process in bacteria is
septation via a ring of FtsZ protein, which is a tubulin-like protein
369
in comparing somatic cells and gametes, somatic cells are
diploid with twice the number of chromosomes
370
what are homologous chromosomes?
two genetically similar chromosomes, one from each parent
371
chiasmata form
between homologous chromosomes
372
crossing over involves each of the following with the exception of
the transfer of DNA between two sister chromatids
373
during anaphase I
homologous chromosomes move to opposite poles
374
at metaphase I the kinetochores of sister chromatids are
attached to microtubules from the same pole
375
what occurs during anaphase of meiosis II?
sister chromatids are pulled to opposite poles
376
which of the following does NOT contribute to genetic diversity?
metaphase of meiosis II
377
how does DNA replication differ between mitosis and meiosis?
during meiosis, there is only one round of replication for two divisions
378
which of the following is NOT a distinct feature of meiosis?
attachment of sister kinetochores to spindle microtubules
379
which phase of meiosis I is most similar to the comparable phase in mitosis?
telophase I
380
structurally, meiotic cohesins have different components than mitotic cohesins. This leads to the following functional difference:
centromeres remain attached during anaphase I of meiosis
381
mutations that affect DNA repair often also affect the accuracy of meiosis. This is because
the proteins involved in the repair of double-stranded breaks are also involved in crossing over
382
what property distinguished Mendel's investigation from previous studies?
Mendel quantified his results
383
the F1 generation of the monohybrid cross purple (PP) x white (pp) flower pea plants should
all have purple flowers
384
the F1 plants from the previous question are allowed to self-fertilize. The phenotypic ratio for the F2 should be
3 purple: 1 white
385
which of the following is NOT a part of Mendel's five-element model?
if an allele is present it will be expressed
386
an organism's __ is/are determined by its __
phenotype; genotype
387
phenotypes like height in humans, which show a continuous distribution, are usually the result of
the action of multiple genes on a single phenotype
388
Japanese four o'clocks that are red and tall are crossed to white short ones, producing an F1 that is pink and tall. If these genes assort independently, and the F1 is self-crossed, what would you predict for the ratio of F2 phenotypes?
3 red tall: 6 pink tall: 3 white tall: 1 red short: 2 pink short: 1 white short
389
If the two genes in the previous question showed complete linkage, what would you predict for an F2 phenotypic ratio?
1 red tall: 2 pink tall: 1 white short1 red tall: 2 pink tall: 1 white short
390
what is the probability of obtaining an individual with the genotype bb from a cross between two individuals with the genotype Bb?
1/4
391
In a cross of AaBbcc x AaBbCc, what is the probability of obtaining an individual with the genotype AABbCc?
1/16
392
when you cross true-breeding tall and short tobacco plants you get an F1 that is intermediate in height. When this F1 is self-crossed, it yields an F2 with a continuous distribution of heights. What is the best explanation for these data?
Height is determined by the additive effects of many genes
393
Mendel's model assumes that each trait is determined by a single factor with alternative forms. We now know that this is too simplistic and that
a single gene can affect more than one trait, and traits may be affected by more than one gene
394
Why is the white-eye phenotype always observed in males carrying the white-eye allele?
Because the allele is located on the X chromosome and males only have one X
395
In an organism’s genome, autosomes are
all of the chromosomes other than sex chromosomes.
396
What cellular process is responsible for genetic recombination?
Crossing over between homologues
397
The map distance between two genes is determined by the
recombination frequency.
398
How many map units separate two alleles if the recombination frequency is 0.07?
7 cM
399
How does maternal inheritance of mitochondrial genes differ from sex linkage?
Since mitochondria are inherited from the mother, females and males are equally affected.
400
Which of the following genotypes due to nondisjunction of sex chromosomes is lethal?
OY
401
A recessive sex-linked gene in humans leads to a loss of sweat glands. A woman heterozygous for this will
have patches of skin with and without sweat glands
402
As real genetic distance increases, the distance calculated by recombination frequency becomes an
underestimate due to multiple crossovers that cannot be scored.
403
Down syndrome is the result of trisomy for chromosome 21. Why is this trisomy viable and trisomy for most other chromosomes is not?
Chromosome 21 is a small chromosome with few genes so this does less to disrupt the genome.
404
Genes that are on the same chromosome can show independent assortment
when they are far enough apart that odd numbers of crossovers is about equal to even.
405
The A and B genes are 10 cM apart on a chromosome. If an A B/a b heterozygote is testcrossed to a b/a b, how many of each progeny class would you expect out of 100 total progeny?
45AB, 45ab, 5Ab, 5aB
406
During the process of spermatogenesis, a nondisjunction event that occurs during the second division would be
better than the first division because only two of the four meiotic products would be aneuploid.
407
What was the key finding from Griffith’s experiments using live and heat-killed pathogenic bacteria?
Genetic material can be transferred from dead to live bacteria.
408
Which of the following is NOT a component of DNA?
The pyrimidine uracil
409
Chargaff studied the composition of DNA from different sources and found that
the proportions of A equal that of T and G equals C.
410
the proportions of A equal that of T and G equals C.
hydrogen bonds.
411
The basic mechanism of DNA replication is semiconservative with two new molecules,
each with one new and one old strand.
412
One common feature of all DNA polymerases is that they
synthesize DNA in the 5′-to-3′ direction.
413
Which of the following is NOT part of the Watson–Crick model of the structure of DNA?
The two DNA strands are oriented in parallel (5′-to-3′).
414
If one strand of a DNA is 5′ATCGTTAAGCGAGTCA3′, then the complementary strand would be:
If one strand of a DNA is 5′ATCGTTAAGCGAGTCA3′, then the complementary strand would be:
415
Hershey and Chase used radioactive phosphorus and sulfur to
differentially label DNA and protein.
416
The Meselson and Stahl experiment used a density label to be able to
distinguish between newly replicated and old strands.
417
The difference in leading versus lagging strand synthesis is a consequence of
both the physical structure of DNA and the action of
| polymerase enzyme.
418
if the activity of DNA ligase was removed from replication, this would have a greater effect on
synthesis on the lagging strand versus the leading strand.
419
Successful DNA synthesis requires all of the following except
endonuclease.
420
the synthesis of telomeres
requires telomerase, which uses an internal RNA as a
| template.
421
When mutations that affected DNA replication were isolated, two kinds were found. In cultures that were not synchronized (that is, not all dividing at the same time), one class put an immediate halt to replication, whereas the other put a much slower stop to the process. The first class affects functions at the replication fork like polymerase and primase. The second class affects functions necessary for
initiation: cells complete replication but cannot start a new round.
422
The experiments with nutritional mutants in Neurospora by Beadle and Tatum provided evidence that
genes specify enzymes.
423
What is the central dogma of molecular biology?
information passes from DNA to RNA to protein
424
In the genetic code, one codon
both a and b
a. consists of 3 bases
b. specifies a single amino acid
425
Eukaryotic transcription differs from prokaryotic in that
eukaryotes have three RNA polymerases
426
An anticodon would be found on which of the following types of RNA?
tRNA (transfer RNA)
427
RNA polymerase binds to a__ to initiate ___ .
promoter; transcription
428
During translation, the codon in mRNA is actually “read” by
the anticodon in a tRNA
429
You have mutants that all affect the same biochemical pathway. If feeding an intermediate in the pathway supports growth, this tells you that the enzyme encoded by the affected gene
acts before the intermediate used
430
the splicing process
can produce multiple mRNAs from the same transcript
431
The enzyme that forms peptide bonds is called peptidyl transferase because it transfers
the growing peptide from a tRNA to the next amino acid.
432
In comparing gene expression in prokaryotes and eukaryotes
Both a and c are correct.
a. eukaryotic genes can produce more than one protein.
c. both produce mRNAs that are colinear with the protein.
433
The codon CCA could be mutated to produce
a silent mutation
434
An inversion will
only cause a mutant phenotype if the inversion breakpoints fall within a gene
435
What is the relationship between mutations and evolution?
mutations can create new alleles
436
In prokaryotes, control of gene expression usually occurs at the
initiation of transcription.
437
Regulatory proteins interact with DNA by
binding to the major groove of the double helix and interacting with base-pairs.
438
In E.coli, induction in the lac operon and repression in the trp operon are both examples of
negative control by a repressor.
439
The lac operon is controlled by two main proteins. These proteins
act in the opposite fashion, one negative and one positive.
440
In eukaryotes, binding of RNA polymerase to a promoter requires the action of
general transcription factors.
441
In eukaryotes, the regulation of gene expression occurs
at the level of transcription initiation, or posttranscriptionally.
442
In the trp operon, the repressor binds to DNA
in the presence of trp
443
The lac repressor, the trp repressor and CAP are all
allosteric proteins that bind to DNA and an effector.
444
Specific transcription factors in eukaryotes interact with enhancers, which may be a long distance from the promoter. These transcription factors then
can interact with the transcription apparatus via DNA looping.
445
Repression in the trp operon and induction in the lac operon are both mechanisms that
allow the cell to control the level of enzymes to fit
| environmental conditions.
446
Regulation by small RNAs and alternative splicing are similar in that both
Both a and b are correct.
a. act after transcription.
b. act via RNA/protein complexes.
447
Eukaryotic mRNAs differ from prokaryotic mRNAs in that they
are not colinear with the genes that encode them.
448
In the cell cycle, cyclin proteins are produced in concert with the cycle. This likely involves
control of initiation of transcription of cyclin genes, and ubiquitination of cyclin proteins.
449
A mechanism of control in E.coli not discussed in this chapter involves pausing of ribosomes allowing a transcription terminator to form in the mRNA. In eukaryotic fission yeast, this mechanism should
not occur as transcription occurs in the nucleus and translation in the cytoplasm.
450
Which of the following is NOT a property of life?
movement
451
The process of inductive reasoning involves
the use of specific observations to develop general principles
452
A hypothesis in biology is best described as
a possible explanation of an observation
453
A scientific theory is
a statement of how the world works that is supported by experimental data.
454
The cell theory states that
All living things are made up of cells
455
The molecule DNA is important to biological systems because
it encodes the information for making a new individual.
456
The organization of living systems is
hierarchical with cells at the base, and the biosphere at the top
457
The idea of evolution
Predated both Darwin and Wallace
458
What is the significance of Pasteur's experiment to test the germ hypothesis?
It demonstrated that cells can only arise from other cells
459
Which of the following is NOT an example of reductionism?
An evaluation of the overall behavior of a cell
460
How is the process of natural selection different from that of artificial selection?
Artificial selection is a result of human intervention.
461
If you found a fossil for a modern organism next to the fossil of a dinosaur, this would
have no bearing on evolution by natural selection and indicate that dinosaurs may still exist.
462
The theory of evolution by natural selection is a good example of how science proceeds because
a. it makes predictions that have been tested by a variety of approaches
b. it represents Darwin's belief of how life has changed over time.
463
In which domain of life would you find only single-celled organisms?
both b and c
b. bacteria
c. archaea
464
Evolutionary conservation occurs when a characteristic is
important to the life of the organism
465
The property that distinguishes an atom of one element (carbon, for example) from an atom of another element (oxygen, for example) is
the number of protons
466
If an atom has one valence electron—that is, a single electron in its outer energy level—it will most likely form
an ionic bond
467
An atom with a net positive charge must have more
protons than electrons
468
The isotopes carbon-12 and carbon-14 differ in
number of neutrons
469
Which of the following is NOT a property of the elements most commonly found in living organisms?
The elements possess eight electrons in their outer
| energy level.
470
Ionic bonds arise from
attractions between ions of opposite charge
471
A solution with a high concentration of hydrogen ions
is called an acid
472
Using the periodic table on page 22, which of the following atoms would you predict should form a positively charged ion (cation)?
Potassium (K)
473
Refer to the element pictured. How many covalent bonds could this atom form?
Three
474
A molecule with polar covalent bonds would
be soluble in water
475
Hydrogen bonds are formed
when hydrogen is part of a polar bond
476
If you shake a bottle of oil and vinegar then let it sit, it will separate into two phases because
non-polar oil is not soluble in water.
477
How is a polymer formed from multiple monomers?
By the removal of an -OH group and a hydrogen atom
478
Why are carbohydrates important molecules for energy storage?
The C—H bonds found in carbohydrates store energy.
479
Plant cells store energy in the form of _________, and animal cells store energy in the form of ___________.
Starch; glycogen
480
Which carbohydrate would you find as part of a molecule of RNA?
Ribose
481
A molecule of DNA or RNA is a polymer of
nucleotides
482
What makes cellulose different from starch?
Cellulose forms long filaments, and starch is highly branched
483
What monomers make up a protein?
amino acids
484
A triglyceride is a form of _______ composed of ___________.
Lipids; fatty acids and glycerol
485
You can use starch or glycogen as an energy source, but not cellulose because
starch and glycogen have similar structures.
486
Which of the following is NOT a difference between DNA and RNA?
Phosphodiester versus hydrogen bonds
487
Which part of an amino acid has the greatest influence on the overall structure of a protein?
the R group
488
A mutation that alters a single amino acid within a protein can alter
all of the choices are correct
| * the primary, secondary, and tertiary structures
489
Two different proteins have the same domain in their structure. From this we can infer that they have
similar function
490
What aspect of triglyceride structure accounts for their insolubility in water?
The non-polar C—H bonds in fatty acids
491
The spontaneous formation of a lipid bilayer in an aqueous environment occurs because
both a and c are correct.
a. the polar head groups of the phospholipids can interact with water
c. the fatty acid tails of the phospholipids are hydrophobic
492
if 18% of the nucleotides from a dsDNA molecule contains the base T, what percent will contain the base G?
32%
493
true or false: transcription and translation occurs simultaneously (coupled) in eukaryotic cells
false
494
an individual with the karyotype 45, XO would have how many Barr bodies?
0
495
let P = purple flowers and p = white flowers, and T = tall plants and t = dwarf. What are the genotypes of the gametes that are produced by a plant that is heterozygous for both traits?
PT, Pt, pT, and pt
496
Viruses that attack bacteria are called
phages
497
Chromosomes that occur in pairs and code for the same traits are called __ chromosomes; these do not include the __ chromosomes which encode for gender.
homologous; sex
498
If a short sequence of DNA is 5' AATTGCCGT 3', its complement is
3' TTAACGGCA 5'.
499
In hemoglobin, the shift from glutamic acid to valine is considered what type of mutation?
point mutation
500
Because the two strands of a DNA molecule are __ to each other, either one can be used as a template to reconstruct the other
complementary
501
true or false: mutations within genes (DNA) always result in non-functional proteins
false
502
what structure is formed by two sister chromatids being held together by a centromere?
chromosome
503
the failure of sister chromatids to separate during meiosis is called
nondisjunction
504
true or false: if a strain of bacteria had a mutation that blocked expression of the lac repressor, the mutant strain would waste energy producing enzymes in the absence of lactose
true
505
You decide to repeat the Meselson-Stahl experiment, except this time you plan to grow the E. coli cells on light 14N medium for many generations and then transfer them to heavy 15N medium and allow them to grow for 2 additional generations (2 rounds ofDNA replication). If the conservative model of DNA replication was correct, what isthe expected distribution of DNA in the density gradient after two rounds ofreplication?
One band of light density and one band of heavy density.
506
You are studying regulation of a prokaryotic operon. Experiments show that expression of the operon is increased when levels of biosynthetic product from that pathway are low. Based on this information, what is a likely mode of regulation?
The product binds a repressor, allowing it to bind the operator
507
certain proteins can bind to specific DNA regulatory sequences by entering
the major groove of the DNA and reading the nucleotide base pairs
508
when during the cell cycle are chromosomes visible?
during mitosis
509
true or false: alternative splicing explains how there are more mRNAs than there are genes on the human genome
true
510
true or false: hemophilia and albinism are recessive traits in humans
true
511
individuals that have 2 alleles for most gene loci are best described as
diploid
512
a woman with blood type O has a child with blood type O. She claims that a man named Ralph is the child's father. Her claim would be proven false if Ralph has blood type:
AB
513
Information obtained by Franklin from X-ray crystallography on DNA suggested that it is shaped like a
helix
514
after attaching to a bacterial cell, a bacteriophage typically
injects DNA into the cell
515
true or false: when studying F2 plants of monohybrid crosses in pea plants, Mendel found that the ratio of the dominant-to-recessive phenotypes were 3: 1
true
516
during translation which site on the ribosome does the incoming tRNA carrying the next amino acid bind?
A- site
517
Irene knows her blood type is A, but William does not know his blood type. However, William knows that his mother and father both had blood type B. Irene and William's first child is a boy with type O blood. Based on this information, William's blood type could be
either B or O
518
during DNA replication, which enzyme removes the RNA primers and then fills in the gap?
DNA pol I
519
specialized cells differ from one another because
they only express certain genes
520
Is this trait shown below dominant or recessive? and What is the genotype of III-3?
recessive/ homozygous recessive
521
Single-stranded ends generated by the same restriction enzyme are complementary to each other. They can be joined together
even when the source of the DNA is different
522
when E. coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the
trp operon
523
A tumor suppressor gene undergoes a mutation that causes it to lose its normal function.What would be the most likely result of this mutation?
The cell no longer responds to signals that cause it to stop dividing or undergo apoptosis.
524
The observable expression of the genes present in an organism is called its
phenotype
525
In Mendel's experiments on seed color in pea plants, when a dominant green seed-bearing plant was crossed with a recessive yellow seed-bearing plant, what was the approximate phenotypic ratio among the F2 generation?
1 yellow: 3 green
526
nucleotides have a phosphate group attached at the __ carbon atom of the sugar
5'
527
which of the following statements is correct?
Meiosis involves 2 divisions and produces 4 non-identical daughter nuclei.
528
true or false: Mendel's Second Law of Independent Assortment states that "Gametes located on different chromosomes are inherited independently of one another"
true
529
As a genetic counselor, you are constructing a human pedigree for a particular disease. You note that every generation shows the trait, suggesting that the trait is
dominant
530
true or false: prokaryotic mRNAs have more introns than Eukaryotic mRNAs.
false
531
if an individual allele has more than one effect on the phenotype, that is called
pleiotropy
532
cold weather can change what aspect of a Himalayan rabbit?
phenotype
533
a karyotype shows chromosomes arranged by
banding patterns, size, and shape
534
amniocentesis is a -
medical procedure permitting prenatal diagnosis of many genetic disorders.
535
true or false: proto-oncogenes function by preventing cells from dividing uncontrollably
false
536
true or false: kinases are a type of internal signal molecule used in controlling the cell cycle
true
537
which statement about the Hershey-Chase experiment is false?
The virus-infected bacteria contained radioactive sulfur.
538
the sequence of the mRNA that would result from transcribing the gene pictured would be
DNA template strand: TACGCTAAT
AUGCGAUUA
539
the sequence of the peptide that would result from transcribing and translating the gene pictured would be
Met-Arg-Leu
540
In your research, you have discovered that Protein X is often ubiquitinated in peoplewith a certain disease. What would you predict about levels of Protein X in these patients?
Levels of Protein X will be low due to degradation in the proteasome.
541
Certain proteins can bind to specific DNA regulatory sequences by entering
the major groove of the DNA and reading the nucleotide base pairs.
542
The enzyme dicer chops dsRNA molecules into small pieces of
miRNA and siRNA.
543
You are studying the effects of specific transcription factors on the activation of gene expression. You notice that one particular transcription factor binds far away from thepromoter of its target gene. What can explain this?
DNA looping brings the transcription factor closer to the promoter and initiatesgene transcription.
544
If you were able to look very closely at a portion of DNA and find methylated histones,you would
be looking at a region of inactive chromatin.
545
If a strain of bacteria had a mutation that blocked expression of the lac repressor, whatwould you expect as a result?
The mutant strain would waste energy producing enzymes in the absence oflactose.
546
BamHI is a Type II restriction enzyme that recognizes the sequence 5' G*GATCC 3',and cuts between the two Gs, leaving a 5' overhang. If you were to digest DNA with BamHI, what would be the sequence of the overhanging sticky ends of the two strands?
5' GATC 3' and 5' GATC 3'
547
The method of DNA replication, where each original strand is used as a template to build a new strand, is called the
semiconservative method.
548
You are working to identify enhancer regions of a particular gene. The best place to look is
primarily upstream of the promoter, possibly some distance away.
549
You have been asked to design a synthetic DNA motif, able to bind transcriptional regulatory proteins. The location on this motif that you will design for protein binding is the
major groove of the DNA double helix.
550
The PCR technique requires a DNA polymerase from an organism that can endure high heat, such as Thermus aquaticus. What step of the protocol makes the heat-stability most necessary?
Denaturation
551
In vertebrates, DNA methylation- the addition of a methyl group to DNA nucleotide - ensures that
once a gene is turned off, it will remain off.
552
Barr bodies —
All of the above
553
In humans, the sickle-cell trait is caused by a single defective allele, but sickle-cell disease only occurs in individuals that are homozygous for the sickle-cell allele. A man and woman each carry the trait, but do not have sickle-cell disease. What is the probability that their first two children will both have sickle-cell disease?
1/16
554
An individual with the karyotype 48, XYYY would have how many Barr bodies?
0
555
disaccharides
sucrose, lactose, and maltose
556
monosaccharides
glucose, galactose, and fructose
