bio Flashcards
(619 cards)
1
Q
A ribonucleoside has a ______ and a ________
A
hydroxyl group on the 2’ and 3’ carbons; purine
2
Q
How many nitrogens are in an imidazole group?
A
2
3
Q
Which of the following structures represents histidine with a protonated side chain?
A
4
Q
Which of the following structures is a ribonucleoside?
A
5
Q
The reaction in which histidine is converted to histamine is catalyzed by what enzyme?
A
histidine decarboxylase
6
Q
What nitrogenous bases contain an imidazole group?
A
Adenine and Guanine
7
Q
The alpha-helical structure of a protein is held together by what type of bond?
A
Hydrogen bonding between carbonyl oxygen and amino hydrogen atoms
8
Q
Triacylglycerols consist of what?
A
Three fatty acid subunits connected to a three-carbon glycerol backbone
9
Q
This molecule is classified as a:
A
deoxyribonucleotide
10
Q
What enzyme unwinds the DNA helix and separates the strands?
A
helicase
11
Q
What enzyme is responsible for reading the DNA template in a 3’ to 5’ direction and synthesizing the complementary strand in a 5’ to 3’ direction?
A
DNA polymerase
12
Q
What enzyme synthesizes a short RNA primer that is used as the starting point for the synthesis of a new strand of DNA?
A
Primase
13
Q
Increased molecular length and bulkiness would generate _____ ________
A
steric hindrance
14
Q
complementary strands are always synthesized in _______ directions
A
opposite
15
Q
What is the function of DNA polymerase α?
A
initiates synthesis in eukaryotes
16
Q
What is the function of DNA polymerase δ?
A
synthesizes new DNA strands complementary to a template and requires an existing 3’ hydroxyl (OH) group to “build off of” as it extends its new strand
17
Q
Examples of post-transcriptional modification include ________, ________, and ________
A
addition of a 5’ cap (specifically, a 7-methylguanylate cap), addition of a 3’ poly-A tail, and splicing
18
Q
What is the start codon?
A
AUG
19
Q
What are the three stop codons?
A
UGA, UAA, and UAG
20
Q
What enzyme possesses a 3’-to-5’ exonuclease activity?
A
DNA polymerase
21
Q
What is incomplete penetrance?
A
clinical symptoms (phenotype) are not always present in individuals who have the disease-causing mutation (genotype)
22
Q
A test cross crosses the organism in question with an organism that is ________ for the ________ trait
A
homzygous; recessive
23
Q
Diseases with high penetrance show what?
A
a high correlation between individuals that have the disease genotype and individuals who exhibit the signs and symptoms of the disease
24
Q
Define the relationship between genetic linkage and the physical locations of two genes on the same chromosome
A
Genes that are physically far apart are less likely to be linked
25
What are the two equations for Hardy-Weinberg equilibrium?
1. p² + 2pq + q² = 1 2. p+q = 1
26
p² and q² correspond to ________ individuals for p and q, respectively
homozygous
27
The 2pq term gives the frequency of _________
heterozygotes
28
__________ removes the positive charge on lysine residues in histone proteins, __________ the level of attraction between positively-charged histones & the negatively-charged DNA backbone. This creates [more or less] space between histones and DNA, making gene transcription easier
Acetylation; decreasing; more
29
The following structure depicts what?
cytosine
30
The following structure shows what?
addition of a methyl at C5
31
Transcription of structural lac genes takes place so the bacterium can metabolize the lactose sugar when lactose is [present or absent]
present
32
Allolactose binds to _______, causing it to dissociate from _______ region, freeing up the _______ region for transcription to take place
repressor; operator; operator
33
cDNA is reverse transcribed from the associated ____ molecule
mRNA
34
cDNA lacks ______
introns
35
cDNA is named for being ____________ to ____
complementary; mRNA
36
In an electrolytic cell, the anode is _______ & the cathode is _______
positive; negative
37
Sanger sequencing involves the use of _______________
dideoxynucleotides
38
What are dideoxynucleotides?
Nucleotides that lack an -OH group on both the 2' and 3' carbons
39
The highest-temperature step of a PCR reaction is the __________ step
denaturation
40
What is the denaturation step?
the step in which the reaction mixture is heated to around 95°C
41
Which cells make myelin in the CNS?
oligodendrocytes
42
Which cells make myelin in the PNS?
Schwann cells
43
What are the resident macrophages of the central nervous system called?
microglia
44
_____ are functional groups in which a carbonyl carbon is attached to another –OR group
Esters
45
Yes or No: Do N atoms have to be attached to at least 1 H atom to be an amine functional group?
No, amines can be attached to multiple R groups and no H atoms
46
Action potentials are what kind of phenomena?
All-or-nothing
47
The extracellular concentration of sodium ions is [greater or less] than the intracellular concentration
greater
48
______ ______ and ________ can affect gene expression
steroid hormones; methylation
49
______ ________ & _________ affect gene expression
steroid hormones; methylation
50
______ ________ bind with nuclear receptors that regulate expression through transcription factors
steroid hormones
51
__________ is a DNA-level covalent modification that is an example of epigenetics
Methylation
52
______ ________ bind to membrane receptors and trigger intracellular signaling cascades that dramatically impact cellular activity
peptide hormones
53
At the peak of an action potential, the membrane potential of the neuron is approximately ___ mV
+40
54
______ ceases to flow into the cell, while voltage-gated ________ channels open to allow ________ to flow out of the cell
sodium; potassium; potassium
55
What is the function of the basal ganglia?
controls fine motor movements
56
What is the function of the inferior colliculus?
transmits signals to the medial geniculate nucleus located within the thalamus
57
What is hyperpolarization?
a state in which the membrane potential is more negative than its resting value
58
when ________ ions are positive, their exit from the cell would make its interior more ________
potassium; negative
59
What are the four functions of insulin?
stimulates glycogenesis, increases triglyceride synthesis, decreases fatty acid oxidation, and facilitates the uptake of glucose into muscle, adipose, and other cells
60
In females, a surge of LH causes what between days 11 and 21 of the menstrual cycle?
causes mature follicles on the ovary to undergo ovulation
61
What is the role of LH in males?
LH binds to its receptors on Leydig cells, stimulating testosterone synthesis and secretion
62
A paracrine agent acts on what?
nearby cells
63
Autocrine agents act on what?
the cell that secreted them
64
Exocrine activity involves what?
the secretion of products through ducts
65
The thyroid-stimulating hormone is secreted by one gland?
anterior pituitary gland
66
TSH acts on the thyroid gland to promote the secretion of which two hormones?
thyroxine (T4) and triiodothyronine (T3)
67
What is the function of thyroxine (T4) and triiodothyronine (T3) hormones?
increase the metabolic rate of nearly every cell in the body
68
What are the two functions of the adrenal mineralocorticoid?
acts on the distal tubules and collecting ducts of the kidney nephron and stimulates sodium retention and potassium secretion
69
The adrenal mineralocorticoid promotes what in the presence of ADH?
water retention
70
Calcium ions, cAMP, and cGMP are all common ______ __________
second messengers
71
True or False: ATP is considered a second messenger
False
72
Insulin is produced in what kinds of cells?
ꞵ cells
73
Glucagon is produced in what kinds of cells?
ɑ cells
74
Somatostatin is produced in what kinds of cells?
delta cells
75
Epsilon cells produce what hormone?
ghrelin
76
Corticotropin-releasing hormone (CRH) is secreted by what structure?
hypothalamus
77
Adrenocorticotropic hormone (ACTH) is released by what gland?
anterior pituitary gland
78
What is the function of ACTH?
acts on the adrenal cortex to release cortisol
79
Name the molecule corresponding to this structure
estradiol
80
·O₂⁻, ·OH, & H₂O₂ are all examples of what?
reactive oxygen species
81
Vitamin E is an ___________
antioxidant
82
What is the order of events in the developmental process of oocytes?
Meiosis I initiation → meiosis I completion → puberty →meiosis II initiation → fertilization → meiosis II completion
83
What are the seven steps of the ejaculatory pathway of sperm?
Seminiferous tubules, epididymis, vas deferens, ejaculatory ducts, urethra, penis (think: SEVE(n) UP)
84
Ovulation in which diploid primary oocytes mature into haploid secondary oocytes occurs when?
after puberty
85
The variability of the menstrual cycle is due to what phase?
follicular phase
86
What is another word for the follicular phase?
proliferative phase
87
The luteal phase lasts for how many days in the menstrual cycle?
14 days
88
What is another word for the luteal phase?
the secretory phase
89
What is the order of the stages of embryonic development from earliest to latest?
Morula, blastula, gastrula, neurulation
90
What hormone mimics LH and maintains the corpus luteum to maintain estrogen and progesterone levels?
Human chorionic gonadotropin (hCG)
91
hCG is what kind of hormone?
peptide hormone
92
What 3 factors causes acidosis due to extended cardiac arrest?
reduced gas exchange, increased serum [CO2], and increased lactic acid production due to anaerobic metabolism
93
After gas exchange in the tissues, blood typically has a higher ______ ________ content, a lower ______ content, and a lower __
carbon dioxide; oxygen; pH
94
What two blood vessels carry deoxygenated blood from the right side of the heart to the lungs to be oxygenated in the lungs?
systemic veins and pulmonary arteries
95
What blood vessels return oxygenated blood to the heart?
pulmonary veins
96
What structures provide electrical conduction to the ventricles?
Purkinje fibers
97
What is the name of the hormone released from blood platelets?
thromboxane
98
What is the name of the enzyme in blood plasma that causes the clotting of blood by converting fibrinogen to fibrin?
thrombin
99
Active exhalation involves contraction of what muscles?
internal intercostal muscles
100
Contraction of the diaphragm is associated with [inhalation or exhalation]?
inhalation
101
What is residual volume?
volume of air remaining in the lungs after an individual has exhaled as much as possible
102
How does the epiglottis protect the lungs?
closes while eating to protect the lungs from swallowed objects
103
Where is surfactant found and function does it serve?
in the alveoli and serves to reduce surface tension
104
What cells produce mucus?
goblet cells
105
Hyperventilation can markedly [increase or decrease] the amount of carbon dioxide in the blood
decrease
106
What kinds of receptors stimulate ventilation in response to increased arterial carbon dioxide levels?
carbon dioxide-sensing chemoreceptors
107
What form of transport is used to exchange gases between the alveoli and the capillaries?
simple diffusion
108
Individuals can only receive blood if [statement]
it does not contain antigens that the recipient makes antibodies against
109
What is required to have a net filtration pressure?
the net pressure must favor movement of fluid from the capillary into the Bowman’s space
110
The fluid movement into the Bowman’s space is [positive or negative]
positive
111
The fluid movement into the glomerular capillary is [positive or negative]
negative
112
What part of the nephron accounts for the majority of transport along the nephron?
the proximal tubule
113
The descending loop of Henle only allows for [passive or active] reabsorption of water
passive
114
The ascending loop of Henle is [permeable or impermeable] to water, and has to [passively or actively] pump ions out of the nephron
impermeable; actively
115
__% of our sample values to fall within 1 standard deviation of the population mean
68
116
__% would fall within 2 standard deviations
95
117
__% of the sample values will be within 3 standard deviations of the population mean
99.7
118
What is oncotic pressure?
a form of osmotic pressure exerted by proteins in a blood vessel's plasma
119
What are the four major proteins in the blood & they each comprise how much % of the blood?
albumins (55%), globulins (38%), fibrinogen, also known as clotting factor I (7%), and clotting factors (<1%)
120
What are the two primary effects of aldosterone?
increases sodium absorption in the distal convoluted tubule and collecting duct of the nephron and causes fluid retention increasing the blood pressure
121
What is the function of the gallbladder?
releases stored bile into the small intestine to help emulsify fats
122
___________ are broken down in the small intestine by enzymes known as _______________
disaccharides; disaccharidases
123
The pancreas is the source of the zymogen form of ______, a ________
trypsin; protease
124
Starch is partially digested in the mouth by what enzyme?
salivary amylase
125
What organ is typically the site of the absorption of significant amounts of water into the body?
large intestine
126
Since cellulose cannot be digested or absorbed, it will remain in the digestive tract, [increasing or decreasing] its osmolarity and [increasing or reducing] the concentration gradient of water
increasing; reducing
127
Vasopressin activity results in what?
retention of water via reabsorption in the collecting duct of the nephron
128
A vasopressin receptor antagonist [increases or decreases] water retention, & [increases or reduces] blood volume
decreases; reduces
129
What is the function of the proximal convoluted tubule?
the site of major reabsorption and secretion that is largely driven by sodium transport
130
What is the function of the distal convoluted tubule?
involved with hormone-controlled reabsorption and secretion
131
What is the function of the Loop of Henle?
create an osmotic gradient
132
What is the function of the collecting duct?
create a concentration of urine
133
What sphincter is composed of skeletal muscle and is under voluntary control?
external anal sphincter
134
What sphincter (there are 2 names) separates the esophagus from the stomach and is under involuntary control?
the gastroesophageal sphincter or the cardiac sphincter
135
What sphincter separates the stomach from the small intestine and is involuntary?
the pyloric sphincter
136
Why are proteins not typically found in urine?
Because they are too large to pass from the blood stream into the filtrate at the nephron
137
True or False: Ketones are normally found in urine
False, ketones are not normally found in urine
138
The presence of ketones in urine is associated with what condition?
diabetes
139
Immunosuppression [increases or decreases] the risk of cancer
increases
140
What is the variable region?
the amino acid sequence that is complementary to the antigenic sequence
141
Antigens bind to the variable region through what kinds of interactions?
noncovalent interactions
142
The blood-brain barrier is formed by what?
capillary endothelial cells
143
What are tight junctions?
closely associated regions of adjacent cells that form a virtually impermeable barrier to fluid
144
True or False: Iron is present in carbonic anhydrase
False, iron is not present in carbonic anhydrase
145
What is carbonic anhydrase?
a metalloenzyme that catalyzes the reversible reaction between carbon dioxide and water
146
The active site of carbonic anhydrase contains a ____ molecule
zinc
147
Respectively, labels A, B, and C refer to
the renal medulla, the renal cortex, and a ureter
148
What kind of selection occurs when the population's alleles are seen to favor more extreme phenotypes over time?
disruptive selection
149
What are centromeres?
heterochromatin-based regions of DNA that assist in the connection of sister chromatids
150
What is transformation?
taking up extraneous information from the environment
151
________ are used in lab settings to incorporate genes of interest into certain cells.
Plasmids
152
What is hyperpolarization?
when the neuron's potential is dropping to a more negative value
153
What is hyperpolarization?
when the neuron's potential is dropping to a more negative value
154
What is anterior-posterior patterning?
changing the poles or zone of polarizing activity
155
What is the function of limb-specific transcription factors?
activate the transcription of specific genes to initiate differentiation
156
What is the function of limb-specific transcription factors?
activate the transcription of specific genes to initiate differentiation
157
An embryo becomes a fetus by the ___ week of development
9th
158
The region marked 2 corresponds to what part of the antibody?
the antigen-binding domain or variable domain
159
What purpose does the variable domain serve?
allows antibodies to recognize very specific antigens
160
What purpose does the variable domain serve?
allows antibodies to recognize very specific antigens
161
Carbon dioxide is a ________ of hemoglobin that binds to the active heme group
substrate
162
Hemoglobin is an iron-containing _____________
metalloprotein
163
Circular loops or linear strands of ssDNA pertain to what organisms?
viruses
164
Linear strands of dsDNA pertain to what organisms?
humans
165
Circular loops of dsDNA pertain to what organisms?
bacteria
166
True or False: Erythrocytes are anucleate & incapable of synthesizing new proteins
True
167
True or False: Erythrocytes are able to produce MHC
False, erythrocytes are unable to produce MHC and do not express it under any circumstances
168
What happens in the first reaction of integration?
integrase cleaves a dinucleotide from the 3' end of a strand of viral DNA
169
Cleaving a dinucleotide from the 3' end of a strand of viral DNA involves the cleavage of a ___ bond
P-O
170
mRNA transcribed from retroviral DNA can be used in what two ways?
to synthesize viral proteins or used as the RNA genome for progeny viruses
171
What is the average molecular weight of an amino acid?
110 Da
172
What is the average molecular weight of an amino acid?
110 Da
173
What is necessary for confirming that a small molecule induces the formation of integrase tetramers from integrase dimers?
visualize the proteins in their native state
174
What is the consequence of using a denaturing agent?
disrupts the interactions between monomers
175
What is the consequence of using a reducing agent?
disrupts any disulfide bonds
176
Na⁺ reabsorption is of utmost importance to the function of what organ?
the loop of Henle
177
Na⁺ reabsorption is of utmost importance to the function of what organ?
the loop of Henle
178
The loop of Henle is where...
Na⁺ is reabsorbed from the filtrate moving through the nephron
179
What causes the depolarization of the neuron that occurs during the action potential?
the massive influx of sodium through voltage gated ion channels
180
Glycolysis produces ___ ATP molecules per glucose molecule
2
181
Glycolysis produces ___ ATP molecules per glucose molecule
2
182
How many Na⁺ molecules are extruded for each ATP molecule utilized by the sodium pump?
3 Na⁺ molecules
183
The protection of glucose in this harsh environment is due to what?
its effects on the diffusion of water
184
Hyperglycemia normally elicits [insulin or glucagon] secretion
insulin
185
[Glucagon or Insulin] secretion is suppressed by hyperglycemia
Glucagon
186
What feature of RNA makes RNA more reactive and unstable than its DNA counterparts?
the presence of a 2' hydroxyl group on ribose
187
What feature of RNA makes RNA more reactive and unstable than its DNA counterparts?
the presence of a 2' hydroxyl group on ribose
188
What is the typical resting potential of a neuron?
-45 mV
189
What is the typical resting potential of a neuron?
-45 mV
190
True or False: Prokaryotic translation does rely on the presence of several release factors
True
191
What release factor do eukaryotes need?
eukaryotic translation termination factor 1 (eRF1)
192
Protozoans are [eukaryotic or prokaryotic] organisms
eukaryotic
193
The cardiac muscle tissue has an action potential with a "_______" in its depolarization whereas the skeletal muscle tissue does not have a "_______."
plateau; plateau
194
Repolarization is delayed due to what?
the action of slow-to-open voltage gated Ca2+ channels
195
the opening of K+ channels in skeletal muscle tissue is able to [slowly or rapidly] repolarize the cell
rapidly
196
What kind of molecule is myoglobin and what is its role?
monomeric and plays an analogous role in maintaining an oxygen reserve in the tissues
197
What are restriction endonucleases?
enzymes that cut DNA at specific sites
198
Restriction endonucleases are used in an early step of ________ ________ procedure, and they can also be utilized to cleave DNA as part of a ______ _______
Southern blotting; repair process
199
The mesodermal layer gives rise to what three structures?
the skeletal system, the cardiovascular system, and the kidneys
200
When traveling from the cortex towards the inside of the body or the medulla, the solute concentration [increases or decreases]
increases
201
True or False: Neurons, epithelial cells, and fat cells would be expected to have a high actin concentration
False, neurons, epithelial cells, and fat cells would not be expected to have a high actin concentration
202
What types of cells should have the highest concentration of actin and myosin?
muscle cells
203
What types of cells should have the highest concentration of actin and myosin?
muscle cells
204
The ______ is the area of the nucleus where the genes that code for ribosomal RNA (rRNA) are transcribed
nucleolus
205
What is one of the functions of the liver?
drug detoxification
206
Stabilizing selection generally results from what?
forces favoring moderate phenotypes over extreme ones
207
When does the bottleneck effect occur?
a disaster or other event results in a loss of a large portion of a population. All future members of a population then descend from a small number of individuals
208
Glucagon increases gluconeogenesis in the _____ and _______ only
liver; kidneys
209
Between meals, glucagon stimulates enzymes in the liver to break down _______ ______ so that glucose can be released into the bloodstream
glycogen stores
210
What is the function of aldosterone?
causes increased absorption of sodium and water
211
True or False: Aldosterone is a fast-acting hormone
False, aldosterone is not a fast-acting hormone
212
Vasopressin is also known as what?
ADH
213
What is vasopressin (or ADH)?
a fast-acting hormone that increases water reabsorption in the collecting ducts of nephrons in the kidneys. It concentrates urine and results in less frequent urination
214
The endoderm gives rise to what?
linings of internal organs (stomach, lungs, intestines, etc.)
215
What structures differentiate from the ectoderm?
epidermis, nervous system, eye lens, and hair
216
What structures differentiate from the mesoderm?
muscle, cardiac and skeletal systems, blood, heart, and spleen
217
The pulmonary veins are adjacent to what structure?
the left atrium
218
Pulmonary veins receive __________ blood from lungs and carry it back to the _____
oxygenated; heart
219
RNA pol I transcribes certain genes into what type of RNA molecule?
rRNA
220
What is lineage potential?
the ability to differentiate into many cell types
221
What is lineage potential?
the ability to differentiate into many cell types
222
As pluripotent cells develop into multipotent cells, they express a [greater, equal, or smaller] percentage of lineage-specific genes due to specialization
greater
223
What is one of the mechanisms used to "turn off" genes not related to newly specialized cells?
DNA methylation
224
In eukaryotes, dsDNA is wrapped around proteins known as what?
histones
225
A DNA-histone subunit is termed a __________
nucleosome
226
Chromatin represents what?
fully packed DNA
227
True or False: Selection pressures can decrease the frequency of a trait even if that trait is not negative and the pressure is not acting directly on that trait
True
228
The term, "wild type," refers to what?
traits an animal typically possesses when found in nature
229
____ ____ usually refers to a dominant trait but not always
wild type
230
What is the epiglottis and what is its function?
a piece of connective tissue that covers the trachea when swallowing food to ensure food goes down the esophagus
231
What structure connects the esophagus to the stomach?
the cardiac sphincter
232
Dyneins carry cargo towards the [ends or center] of the cell
center
233
Where is the microtubule organizing center (MTOC) located?
close to the center of the cell
234
Microtubules grow from the [positive or negative] end, so the end is located towards the periphery of the cell while the [positive or negative] ends are found close to the center
positive; negative
235
Kinesins travel toward the [positive or negative] ends of microtubules
positive
236
What is the likelihood of independent assortment for genes on different chromosomes?
50%
237
Lipase’s ability to catalyze the hydrolysis of fats and similar molecules reveals what?
some enzymes interact with several different substrate molecules that have similar chemical linkages
238
Upon undergoing meiosis and distributed to the cytoplasm to two daughter cells, most of it goes to the daughter cell destined to be the ____
ovum
239
The daughter cells that are cast off with little cytoplasm are called what?
polar bodies
240
An antisense drug works to prevent what?
the expression of undesirable genes
241
What is the only way to cure PKU?
add a gene that could lead to the production of effective enzymes to replace the ones that do not function correctly
242
The coordination of cell differentiation during development is extremely sensitive to what?
the timing of mRNA turnover
243
Prolonged increase in heart rate and breathing rate is caused by what?
insufficient blood hemoglobin to supply oxygen for exercise at low oxygen pressure found at high altitudes
244
What is myoglobin?
the substance that holds oxygen in the muscles and organs
245
During anaphase of mitosis, sister chromatids are pulled apart at the ____________, each becoming an independent chromosome in the two diploid daughter cells
centromeres
246
What happens during anaphase I of meiosis I?
homologous pairs of chromosomes are separated into two daughter cells
247
The centromere is split and the sister chromatids separate during what phase of meiosis II?
anaphase II
248
Mammalian skin is involved with what three functions?
touch sensation, protection from disease, and protection against internal injury
249
Within a sarcomere, the microfilament length remains ______
stable
250
Because one end of the microfilament is anchored in the Z line, actin monomers are prevented from what?
being added to or subtracted from that end
251
To retain a stable length, both ends of the microfilament must be
capped
252
What are cytochalasins?
drugs that inhibit the growth of microfilaments
253
E. coli bacteria is a species common to what anatomical structure?
colon
254
The _______ is continuous with the _____ so that bacteria can move between these two structures
appendix; colon
255
A reducing agent is used during SDS-PAGE for what purpose?
to cleave disulfide bonds
256
Disulfide bonds hold what?
two separate subunits of different masses together
257
True or False: Phosphodiester bonds contribute to the stabilization of protein structure
False, phosphodiester bonds do not contribute to the stabilization of protein structure
258
____________ _____ link adjacent nucleotides in DNA
Phosphodiester bonds
259
What type of inhibitors do not alter the slope of the Lineweaver–Burk plot, which is equal KM/Vmax?
uncompetitive inhibitors
260
Uncompetitive inhibitors bind their target enzymes only when what?
the substrate is first bound to the enzyme
261
At higher substrate concentrations, the substrate–enzyme complex are more abundant, so the uncompetitive inhibitor will work most effectively when the substrate concentration is the [highest or lowest]
highest
262
What is the glomerulus?
a tuft of capillaries that bulges into the capsular space, which is a potential space lined with simple squamous epithelium
263
Fluid is expressed from the blood across the _________ ___________
capillary endothelium
264
What is the pathway of fluid through capillary endothelium?
capsular space → kidney tubule → proximal tubule → U-shaped loop of Henle → distal tubule
265
The amount of glucose in the fluid in the capsular space as it enters the tubule system would be [greater than, the same as, or less than] the amount of glucose in the plasma
the same as
266
As blood is lost from the circulation, reduction in vessel size helps with what?
maintaining the necessary pressure to keep the blood circulating to all body tissues
267
Vasoconstriction, the narrowing of a vessel, restricts blood flow to an organ and can [increase or decrease] blood pressure
increase
268
Sperm motility requires [small, medium or large] amounts of ATP as evidenced by the [low, medium, or high] concentration of mitochondria in the sperm midpiece
large; high
269
What are mutations?
heritable changes in the sequence of the nucleic acid component of chromosomes
270
Mutations that lead to unregulated cellular growth can lead to what?
cancer
271
Secondary spermatocytes are the products of meiosis I, where [diploid or haploid] cells are first formed
haploid
272
Erection is triggered by [sympathetic or parasympathetic] nervous stimulation
sympathetic
273
The ectoderm produces what four anatomical structures?
epidermis, nervous system, eye lens, and hair
274
Veins contain a layer of ______ muscle in their walls
smooth
275
What are the three common characteristics of smooth muscle?
one nucleus per cell, rounded cells with tapered ends, and a lack of striation found in other muscle types
276
Homologous chromosomes separate during anaphase of meiosis I, producing cells that are [diploid or haploid]
haploid
277
Stimulation of oxytocin receptors located in the uterine wall increases ________ ___________, which causes increased ________ _______ during subsequent contractions
uterine elasticity; uterine stretch
278
Glucagon stimulates ________________ in liver cells so that glucose can be made from non-sugar substrates
gluconeogenesis
279
The H zone refers to what?
the non-overlapping area between thin filaments in the center of the sarcomere
280
True or False: Thin and thick filaments slide relative to one another
True, thin and thick filaments slide relative to one another
281
The Z line is the name given to what?
junction or "border" at either end of the sarcomere
282
The Z line is __________ to the direction of contraction
orthogonal
283
Antibodies are recognized based upon their _____ ______
heavy chains
284
Regions 1,3, and 4 refer to what?
heavy chains
285
Heavy chains are part of the [variable or constant] region
constant
286
The Bohr effect characterizes what?
the inverse relationship between binding affinity and plasma carbon dioxide concentration
287
When the concentration of carbon dioxide increases, hemoglobin [increases or decreases] its affinity for oxygen
decreases
288
When the concentration of carbon dioxide decreases, hemoglobin [increases or decreases] its affinity for oxygen
increases
289
What is hybrid vigor?
a phenomenon in which the recessive gene persists due to the advantage of being heterozygous
290
Paracrine activity involves the secretion of what?
local signaling molecules known as paracrine factors diffuse to nearby target cells
291
What is the role of the wall of the artery?
acts as a semipermeable membrane setting up the conditions needed for osmosis to occur
292
An increase in plasma albumin will upset the osmotic balance because the blood will become [hypotonic, isotonic, or hypertonic] with respect to the tissue
hypertonic
293
The liver can partially regenerate after illness or damage through what process?
mitosis
294
Mitosis is the process whereby [human body cells or gametes] reproduce
human body cells
295
The ability to produce ATP via ATP synthase is common to both __________ and _____ cells
bacterial; human
296
Where does ATP synthesis take place in bacterial cells?
the plasma membrane
297
Where does ATP synthesis take place in human cells?
inner mitochondrial membrane
298
Most bacterial chromosomes are ________ whereas human chromosomes are ______
circular; linear
299
Work is equal to what?
the product of the force applied to an object and the distance over which the object is moved
300
What is convergent evolution?
a process whereby distantly related organisms independently evolve similar traits to adapt to similar needs
301
Gonadotropin-releasing hormone regulates _________ ____________ (luteinizing hormone and follicle-stimulating hormone) secretion
pituitary gonadotropin
302
If gonadotropin-releasing hormone is not able to regulate luteinizing hormone and follicle-stimulating hormone secretion from the pituitary, the ____________ axis will remain quiescent
reproductive
303
Inhibition of apoptosis is a characteristic of what types of cells?
cancer cells
304
Decrease transport of Ca2+ to the extracellular environment,increase availability of intracellular Ca2+ to bind to troponin, & increase overall Ca2+ stores in the sarcoplasmic reticulum lead to what?
an increase in intracellular calcium levels, resulting in enhancement of the contractile force of the heart
305
Na⁺K⁺+ ATPase is an example of what type of membrane transport?
primary active transport
306
The autonomic nervous system is part of the [central or peripheral] nervous system
peripheral
307
The adrenal medulla secretes what two hormones in response to short-term stress?
epinephrine and norepinephrine
308
Reactions to short-term stress are mediated by the ____________ branch of the autonomic nervous system
sympathetic
309
Osmotic pressure is [directly or indirectly] proportional to solute concentration
directly
310
Imprinted genes are expressed in what kind of manner?
parent-specific manner
311
if protein synthesis was under way when the radioactive amino acids were added, then the [C-terminal or N-terminal] end and probably the ______ part of the protein were already synthesized before the addition of the radioactive amino acids
N-terminal; middle
312
RNA viruses require what type of enzyme to replicate themselves?
transcriptase
313
The structure of the glomerular capillaries serves what function?
to prevent the entry of large molecules, such as proteins, into the filtrate
314
What are epithelial cells and where are they found?
specialized cells for secretion and are found in the respiratory tract
315
How is serotonin removed from the synaptic space?
by transport of released serotonin back into the presynaptic terminal
316
Transport of released serotonin back into the presynaptic terminal, an action that _____ block
SSRIs
317
Large plasma proteins, such as albumin, in the blood [increase or decrease] the osmotic pressure of the blood, which in turn, [increases or decreases] the return of fluid to the circulatory system from the body tissues
increase; increases
318
With malnutrition, the osmotic pressure of the blood would [increase or decrease] resulting in an [increase or decrease] of fluid in the body tissues
decrease; increase
319
To increase calcium levels in the blood, osteoblast activity should be [increased or decreased] and osteoclast activity should be [increased or decreased] to release stored calcium from the bone to the bloodstream
decreased; increased
320
Blood is filtered into ________ _____ within Bowman’s capsule and then moves sequentially through the ________ ______, the ____ __ _____, ___ ______ ______, and the __________ ____
Bowman’s space; proximal tubule; loop of Henle; distal tubule; collecting duct
321
The sympathetic nervous system directly inhibits what two processes?
peristalsis and secretion of digestive enzymes
322
Sympathetic nervous system [increases or decreases] the blood glucose concentration and causes [constriction or dilation] of the blood vessels that supply the deep muscles and internal organs, which aids nutrient delivery to these tissues
increases; dilation
323
Blocking the reuptake of NE into the nerve terminal leaves [more or less] NE in the synapse where it can continue to stimulate the adrenergic receptors on the membrane of the tissue supplied by the neuron
more
324
What is triggered when an action potential reaches a nerve terminal?
opening of Ca+ channels in the neuronal membrane
325
Because the extracellular concentration of Ca+ is greater than the intracellular Ca+ concentration, Ca+ flows [into or out of] the nerve terminal
into
326
A change in membrane potential from –60mV to –70mV indicates what?
the cell membrane is most likely repolarizing to its resting potential of -70mV following an action potential
327
In a neuron, how does the cell membrane repolarize to its resting potential?
by opening the K⁺ channels that release K⁺ from the cell to counterbalance the influx of Na⁺ that occurred during depolarization
328
Blood flows from where to where to where?
arteries to capillaries and then to veins
329
As molecular weight increases, the rate of filtration is expected to [increase or decrease]
decrease
330
Uracil is a component of what molecule?
RNA
331
What happens in starvation?
the body uses up its stores of carbohydrate and lipids, and then begins to break down body proteins for metabolic energy
332
What is a byproduct of the metabolism of the amino acids from protein?
nitrogen
333
What is the reason animals have kidneys?
to provide a way of eliminating nitrogenous waste products
334
True or False: The diaphragm relaxes during inspiration
False, the diaphragm does not relax during inspiration
335
Elevation of the rib cage serves what function?
increases the volume inside the chest cavity
336
Reduction of pressure inside the pleural cavity causes what?
air to move into the lungs
337
Contraction of the external intercostal rib muscles serves what function?
helps the chest expand
338
How does atropine prevent acetylcholine from exerting its effect?
by preventing its binding to the acetylcholine receptor
339
What autonomic nerve fibers innervate the heart to slow it down?
the parasympathetic motor fibers of the vagus nerve
340
Multiple pathways to ganglia lead to what?
more rapid response of the sympathetic system
341
Hydrolysis of acetylcholine results in [increased or decreased] acetylcholine levels
increased
342
What is the name of the enzyme that breaks down acetylcholine?
acetylcholinesterase
343
What is the purpose of removing acetylcholine from the synapse?
to make sure the neurotransmitter can no longer activate its receptor
344
How do many viruses form infective particles (virions)?
by budding off the surface of eukaryotic cells and become enclosed in a vesicle composed of the host’s cell membrane
345
Eukaryotic cell membrane is made up of what?
a bilayer of amphipathic lipids with associated proteins
346
What is one of the characteristics of viruses?
they are obligate intracellular parasites
347
Viruses are unable to reproduce without the aid of what?
the host cell’s metabolic machinery
348
How do viruses make more virus particles?
by taking advantage of the elaborate intracellular mechanisms of the host cell
349
True or False: Viruses can be grown in tissue culture
True
350
Transcription is _______
copying
351
Translation is ________ ___ ________
changing the language
352
How do viruses make proteins?
by translating their specific RNAs into protein
353
The initial source for energy replacement is from hepatic glycogen indicating upregulation of what process?
glycogen breakdown (glycogenolysis)
354
After hepatic glycogen stores are exhausted the glucose pool must be replenished from non-carbohydrate sources implying upregulation of what pathway?
the gluconeogenic pathway
355
What three compounds are used in gluconeogenesis?
lactate, oxaloacetate, and α-ketoglutarate
356
Following glucagon binding to its receptor and activation of its coupled G protein, activities of the adenylate cyclase and the protein kinase A, and level of cAMP are all [increased or decreased]
increased
357
Activation of the G protein promotes what?
the dissociation of bound GDP and its exchange for GTP on the α subunit
358
Exposure to high glucose levels results in [elevated or lowered] levels of circulating insulin which prevents mobilization of endogenous glucose storage
elevated
359
What is the technique used to detect a particular sequence in a sample of RNA?
Northern blotting
360
What is the technique used to detect a particular sequence in a sample of DNA?
Southern blotting
361
Parathyroid hormone promotes what function?
the breakdown of bone tissue
362
How does the body respond when the level of calcium in the blood plasma is low?
by mobilizing stores of calcium from the bones via the activity of parathyroid hormone
363
Parathyroid hormone will [increase or decrease] the number of osteoclasts
increase
364
Calcitonin reduces ____ __________
bone resorption
365
When does bone resorption occur?
when the level of calcium in the blood plasma is low
366
Removal of the parathyroid gland would lead to ____________, a condition of low blood calcium, resulting from the lack of parathyroid hormone
hypocalcemia
367
What is one of the key factors that determines a species?
the ability to successfully breed and produce fertile offspring
368
An aldosterone deficiency would result in [higher or lower] Na+ reabsorption into the bloodstream
lower
369
Decreased blood volume would result in [increased or decreased] blood pressure
decreased
370
The double stranded daughter DNA molecule would be an _____ _________ of the parent molecule
exact duplicate
371
The nitrogenous base, uracil, combined with the sugar ribose and phosphate makes up what nucleotide?
uridine
372
Uridine is found in ___, but not in ___
RNA; DNA
373
Nervous tissue arises developmentally from what germ layer?
ectoderm
374
Circulatory, bone, and dermal tissue all arise from what germ layer?
mesoderm
375
Because ATP synthesis is driven by a flow of hydrogen ions down a concentration gradient, ATP production will [increase or decrease] and eventually ____ as equilibrium is established
decrease; stop
376
Any disruption of mitochondria is likely to [increase or decrease] ATP production since they are a major cellular source of that molecule
decrease
377
What would occupy the active site on the ATP synthase molecule?
ATP or precursor molecules such as phosphate and ADP
378
What would disrupt the electrochemical gradient responsible for the necessary flow of protons?
an influx of another positively charged ion
379
Males specifically pass down their own chromosomes to their [sons or daughters]
daughters
380
In order to regulate blood glucose levels, glycogen is made, stored, and broken down in where?
the liver
381
An increase in acetylcholine receptors on the postsynaptic membrane would [enhance or diminish] transmission
enhance
382
What types of muscles contain striated muscle fibers?
skeletal and cardiac muscles
383
True or False: Cells progressively differentiate to achieve their final specification
True
384
What is the name of the hormone responsible for triggering ovulation?
luteinizing hormone
385
When vasodilation occurs, the walls of blood vessels [contract or relax], allowing [more or less] blood to enter the area
relax; more
386
The presence of increased blood within dilated vasculature in cutaneous tissue allows for what?
allows heat to escape from the surface of the body into the environment
387
The organism with the highest body temperature in response to elevated external temperatures is the organism that is [least or most] able to utilize the cooling mechanisms of vasodilation and sweating
least
388
How may the human body gain heat?
by absorbing radiation from the sun
389
The major dissolved components of bile are breakdown products of __________ such as bilirubin and bile salts
hemoglobin
390
Bile salts allow dietary fats (and oils) to form what?
an emulsion of tiny droplets dispersed in the digestive juices
391
How does the dispersion of fats in the aqueous digestive juices and aid digestion?
by making them available to digestive enzymes
392
Histones come together with DNA to form what?
nucleosomes
393
What are nucleosomes?
the bead-like, primary structural elements of chromatin
394
Long bones grow through what process?
endochondral ossification
395
Endochondral ossification requires what?
cartilaginous growth plates at the ends of long bones that thicken as cartilage and later become ossified
396
In a eukaryotic cell, transcription occurs where?
in the nucleus
397
Sweat glands secrete onto the surface of the skin through what?
channels continuous with the epidermis
398
How do channels continuous with the epidermis prevent water loss?
by isolating the water-permeable, sweat-secreting cells from dry surface air
399
What are the openings of the sweat glands on to the surface of the epidermis called?
pores
400
Phosphatases are responsible for what?
cleavage of phosphate bonds utilizing water to remove a molecule of inorganic phosphate
401
How is the antibody is most likely to act?
by inhibiting the activation of the process that will result in the release of harmful molecules
402
True or False: Antibodies are often generated when an organism cross react with other organisms
True
403
The lack of what mechanism is a limitation for bacteria
the lack of a mechanism splicing introns
404
Organic acids can fully dissociate when the pH of blood is [higher or lower] than the pKa of organic acids
higher
405
What is cytochrome c?
a heme protein that cycles between a ferrous (Fe⁺²) and ferric (Fe⁺³) state during oxidative phosphorylation
406
How many electrons are transferred in cytochrome c in oxidative phosphorylation?
one electron
407
The best primers for PCR have a high __ content and __ bases in 5′ and 3′
GC; CG
408
What is nondisjunction?
the process when paired chromosomes or duplicated chromosomes fail to separate and segregate in two distinct daughter cells
409
What is an inherent property of transport proteins?
transport affinity for substrates
410
The metabolic rate is an internal variable that will help define what?
the capability of an organism to withstand long periods of nutrient deprivation
411
An organism that has a [low or high] metabolic rate will be more suitable to withstand long periods of food deprivation than an organism that has a [low or high] metabolic rate
low; high
412
Cells produce how many molecules of ATP in aerobic conditions?
30 molecules of ATP
413
Cells produce how many molecules of ATP in anaerobic conditions?
2 molecules of ATP
414
Actin is a what?
microfilament
415
Intermediate filaments serve what function?
mostly provide mechanical support to the plasma membrane and position the nucleus in the cell
416
____________ are the site of ATP production
Mitochondria
417
The head of a fatty acid is what?
-CO₂⁻-, a carboxyl group
418
HCO₃⁻ is derived from the dissociation of _____, which is made by _______ _________
H₂CO₃; carbonic anhydrase
419
By moving one-by-one along the capillary, there is [more or less] RBC surface that is available for gas exchange
more
420
What enzymes cleave within DNA nucleotide chains?
endonucleases
421
What enzymes cleave the last nucleotides on either side of DNA nucleotide chains?
exonucleases
422
What enzymes cleave bonds in RNA nucleotide chains?
ribonucleases
423
Cleavage of peptide bonds is catalyzed by what enzyme?
protease
424
Threonine (Thr) is a _____ and ___________ amino acid
polar; hydrophilic
425
What are the four stages of the human female life cycle in order?
fertilization → birth → puberty → menopause
426
The reproductive tract, respiratory tract, and gastrointestinal tract all contain what?
an element of mucosa
427
Glucocorticoid secretion by the adrenal medulla [increases or decreases] with stress
increases
428
The need to conserve water in the body would lead to an [increase or decrease] in aldosterone secretion that would promote the retention of sodium ions
increase
429
Antidiuretic hormone (ADH or vasopressin) secretion would increase for what purpose?
to enhance the permeability of the distal tubules and collecting ducts of the kidney to promote water reabsorption and excretion of more concentrated urine
430
What is aldosterone?
a hormone released by the adrenal glands
431
How do physiologically normal kidneys respond to aldosterone?
by increasing the reabsorption of both sodium and water leading to an increase in blood volume and therefore blood pressure
432
Reduced flow of blood through the renal arteries due to the clamps would cause an [increase or decrease] in glomerular blood pressure
decrease
433
How do kidneys respond to a drop in glomerular blood pressure?
by activating the renin–angiotensin system of hormones
434
Enhanced activity of what types of muscles in blood vessels would cause vasoconstriction?
smooth muscles
435
What is the primary process that takes place in the colon?
absorption of water
436
What would happen if an ulcer penetrated the walls of the intestine?
the contents of the gastrointestinal tract would enter the peritoneal cavity
437
Antigens are carried on what?
the surface of cells
438
Adaptive radiation involves what?
the divergence of one species into multiple species over time
439
When can adaptive radiation occur?
when subgroups of the original species are separated or isolated in different environments so that these subgroups evolve independently of one another
440
What causes the membrane potential to become more positive?
sodium ions moving into the neuron
441
If calcitonin inhibits osteoporosis, it must serve what function?
to take calcium out of the blood and into the bone while preventing the loss of calcium from bone into the blood
442
High levels of blood calcium available for deposit into bone should [stimulate or inhibit] release of calcitonin
stimulate
443
What happens when glycerol reacts with three different fatty acids?
only carbon 2 in the resulting triacylglycerol is attached to four different groups
444
How many fatty acids would be obtained if one of the R groups in the triacylglycerol contained a carbon–carbon double bond and if isomerization of the double bond occurred during the saponification reaction?
four fatty acids
445
Solubility is determined by what?
Henry's law
446
What is Henry's law?
H=c/P
447
Cytochrome P450 acts as what?
monooxygenases
448
What are monooxygenases?
where an oxygen atom is inserted into a substrate (the drug of interest)
449
Tyrosine has a ______________ _______ _____ that attacks the terminal phosphate group (γ-PO₃²⁻) on ATP, resulting in the exchange of the hydrogen atom of a _______ _____ for a phosphate group of ATP
nucleophilic hydroxyl group; hydroxyl group
450
What is the defining characteristic of a transcription factor?
it has a DNA-binding domain that allows it to bind to regulatory nucleic acid sequences in a gene to alter transcription
451
In the payoff phase, how are the four molecules of ATP produced?
the first two ATP molecules are produced in the conversion of 1,3-bisphosphoglycerate to 3-phosphoglycerate, and another two ATP molecules are produced in the conversion of phosphoenolpyruvate to pyruvate
452
What is a mature ovum?
the female gamete that has completed meiosis and contains the haploid number of maternally derived chromosomes
453
What are spermatozoa?
the mature male gametes that contain the haploid number of paternally derived chromosomes
454
Phagocytosis requires what?
that the cell change shape dramatically as it surrounds and engulfs large extracellular particles
455
What are microtubules?
one of the cytoskeletal elements that help determine cell shape
456
Cell shape relies on the ability of what?
the microtubules to disassemble and reorganize
457
Where does glycolysis occur?
in the cytoplasm
458
Where does the citric acid cycle occur?
in the matrix of mitochondria
459
To compensate for the increased body temperature in a fever, skin capillaries [constrict or dilate] to dissipate heat through the skin
dilate
460
What is the diaphragm?
a muscular partition between the abdominal and thoracic cavities and is dome-shaped at rest curving up toward the lungs and heart
461
What characteristic do arteries, veins, and capillaries have in common?
they all possess an inner layer of endothelial cells
462
The pancreas produces several ___________ _______
proteolytic enzymes
463
Proteolytic enzymes produced by the pancreas are released into the small intestine where they are converted to their active forms of _______, ____________, and ________________
trypsin, chymotrypsin, and carboxypeptidase
464
What types of cells have one of the highest rates of mitosis among non-cancerous cells?
epithelial cells of the skin
465
The restriction point is a point in __ of the cell cycle, and after it is passed the cell is committed to division
G₁
466
The G₂ checkpoint checks for what?
DNA damage after DNA replication
467
What happens if damage is detected by the G₂ checkpoint?
"pauses" cell division until damage is repaired
468
Microtubules are responsible for what?
the movement of fully duplicated chromosomes away from each other from the metaphase plate
469
What is lymphoma?
a cancer that arises from cells that are part of the body's immune system
470
[Males or Females] are much more likely to be affected by an X-linked disease
Males
471
Why are males more likely to be affected by an X-linked disease than females?
they only have one copy of the X chromosome
472
What are the 4 possible RNA bases?
A, G, C, and U
473
What are the 3 possible stop codons that do not code for amino acids?
UAA, UAG, and UGA
474
What is a genetic bottleneck?
a reduction in gene-pool diversity because of a sharp reduction in population size
475
What does p² represent?
the frequency of homozygous dominant individuals
476
What does 2pq represent?
the frequency of heterozygous individuals
477
What does q² represent?
the frequency of homozygous recessive individuals
478
What is sympatric speciation?
describes reproductive isolation that emerges when no physical barrier separates a population
479
What is directional selection?
where a more extreme phenotype is favored
480
Why does allopatric speciation occur?
because of physical barriers
481
Geographic isolation, separating the Asian and European samples, is a common cause of what?
allopatric speciation
482
When does leakage occur?
when genes from one species flow to another
483
Penetrance reflects what?
the proportion of individuals in a population who express a certain genotype
484
Expressiveness reflects what?
the strength with which the phenotype is expressed
485
The descending limb, extending from cortex into the salty medulla, is highly permeable to _____ but impermeable to ____
water; NaCl
486
The ascending limb, traveling from the loop's lowest point in the medulla back toward the cortex, is impermeable to _____ but permeable to ____
water; NaCl
487
Juxtamedullary nephrons have long loops of Henle extending deep into the salty medulla to [maximize or minimize] water reabsorption
maximize
488
Cortical nephrons have shorter loops of Henle extending shorter distances into the medulla, making them [more or less] efficient at water reabsorption
less
489
What happens on binding antigens presented by B lymphocytes?
helper T cells release cytokines that stimulate B lymphocyte proliferation
490
What cells respond to antigens by releasing toxins that induce apoptosis (cell death) in nearby infected cells?
natural killer & cytotoxic T cells
491
What happens during prophase?
chromatin condenses into distinct chromosomes and the nuclear envelope disintegrates
492
[Greater or Less] stability decreases the activation energy Ea necessary for the molecules to react, allowing them to reach the energy threshold more often at any given temperature
Greater
493
What is phosphoglycerate mutase?
an enzyme that catalyzes the reversible conversion of 3-phosphoglycerate (3-PG) to 2-phosphoglycerate (2-PG)
494
Potassium (K⁺) leak channels help maintain the membrane potential by enabling what form of transport of K⁺ out of the cell?
passive transport
495
______ _____ pumps embedded in the outer membrane of neurons hydrolyze adenosine triphosphate to provide energy to transport molecules against their concentration gradient
active transport
496
Name the general steps involved during the life cycle in order
Attachment, viral genome entry, host genome degradation, synthesis, and release
497
What is a prominent feature of bacteriophages that have a lysogenic life cycle?
they attach to the bacterium but integrate their genome into the host DNA
498
Proteins with the shortest amino acid sequences have [lower or higher] molecular weights and migrate more [quickly or slowly] through the gel.
lower; quickly
499
How does the DNA mismatch repair machinery work?
a nuclease enzyme excises the erroneous nucleotide, as well as several nucleotides flanking either side of the incorrectly matched base, from the daughter strand
500
What does heterochromatin consist of?
DNA that is tightly coiled around histone proteins, bound by an ionic interaction between the negatively charged phosphates on the DNA backbone and positively charged lysine residues in the histone
501
When and how are euchromatin formed?
when histones are modified, often by acetylation of lysine residues
502
In DNA synthesis, the template strand is always ____________ to the new strand that is being synthesized
complementary
503
Systemic circuit distributes [oxygenated or deoxygenated] blood containing nutrients to all body tissues via [arteries or veins]
oxygenated; arteries
504
When oxygenated blood reaches the capillaries within the systematic tissues, it delivers __ and nutrients to the tissues and picks up ___
O₂; CO₂
505
Veins return the [oxygenated or deoxygenated] blood back to the ______ so it can enter the pulmonary circuit
deoxygenated; heart
506
Pulmonary circuit pumps [oxygenated or deoxygenated] blood through the pulmonary arteries to capillaries in the lungs to facilitate ___ _______
deoxygenated; gas exchange
507
Pulmonary veins then return the [oxygenated or deoxygenated] blood [to or away from] the heart so it can be pumped through the systematic circuit
oxygenated; to
508
What is the effect of calcitonin and how does it perform its function?
stimulates bone formation by increasing osteoblast activity and decreasing osteoclast activity
509
What are promoters?
upstream DNA sequences in the eukaryotic genome that bind with transcription factors
510
How does doxycycline function?
by competing for aminoacyl-tRNA for binding to A site of the 30S ribosome subunit
511
True or False: Testosterone is a peptide hormone
False, testosterone is a steroid hormone
512
As a hormone, how is testosterone transported?
throughout the body in the circulatory system
513
True or False: Testosterone must bind to a transport protein
True, testosterone must bind to a transport protein
514
Malate is reversibly oxidized by the microsomal enzyme ______ _____________, producing ____ and ____________
malate dehydrogenase; NADH; oxaloacetate
515
Isocitrate is formed from citrate by what enzyme?
aconitase
516
Isocitrate is catalyzed by __________ ____________, producing _____________ and ______ ________
isocitrate dehydrogenase; ɑ-ketoglutarate; carbon dioxide
517
What does a virus do to bacteria in the lytic phase?
a virus will infect and kill bacteria
518
What does a virus do to bacteria in the lysogenic phase?
a virus incorporates into the bacterial genome and allows the bacteria to grow and reproduce
519
True or False: DNA is a less compact structure compared to heterochromatin and euchromatin
True, DNA is a less compact structure compared to heterochromatin and euchromatin
520
Because norepinephrine is a mediator of the sympathetic nervous system response, it may lead to what?
side effects associated with sympathetic activation such as high blood pressure
521
What is the nuclear localization signal?
a sequence that tags the protein for it to be transported into the nucleus
522
What is the only step of cellular respiration where NAD⁺ is neither reduced to form NADH, nor is NADH oxidized to form NAD⁺?
chemiosmosis
523
The _________ _______ __ ___ __________ ____ is the last portion of the tubules where water reabsorption can occur
medullary portion of the collecting duct
524
Membrane depolarization is due to what?
the opening of Na⁺ channels
525
Membrane depolarization is a process that is [independent or dependent] from the Na⁺/K⁺ ATPase
independent
526
The restoration and maintenance of the resting potential relies on what?
Na⁺/K⁺ ATPase
527
Transcription factors and regulate the expression of other genes by binding to the promoter or the enhancer of the gene located on what?
DNA
528
In protein kinase enzymes, _____________ is the activating event
phosphorylation
529
What is the role of ABC transporter proteins?
to use ATP to actively transport molecules such as drugs out of the cell
530
What are lipid rafts?
cholesterol-rich domains within the membrane
531
What are the three pressures that work together to regulate filtration in the glomerulus?
glomerular capillary pressure, capsular hydrostatic pressure, and blood colloid osmotic pressure
532
___________ ___________ ________ will force filtrate from a capillary into Bowman's capsule
glomerular capillary pressure
533
True or False: Electrolytes are actively transported from the glomerulus into Bowman's capsule
False, electrolytes are not actively transported from the glomerulus into Bowman's capsule
534
What is a direct consequence of protein degradation in muscles?
increased muscle weakness
535
Anaerobic metabolic pathways can produce energy [with or without] using oxygen by glycolysis
without
536
Microfilaments are composed of what?
actin
537
This is the structure of what molecule?
serine
538
True or False: Serine can be phosphorylated
True
539
A Southern blot uses what to differentiate between mutant and wild-type alleles?
a restriction digest
540
Palindromes are how many base pairs long?
4 to 6 base pairs
541
What is the recognition sequence for HindIII?
AAGCTT
542
True or False: The hypothalamus secretes ghrelin
False, the stomach and small intestine secrete ghrelin
543
The levels of circulating insulin will [increase or decrease] after a meal due to an increase in blood glucose levels
increase
544
Because of a feedback mechanism, the levels of circulating ghrelin are the [same or opposite] of the amount of weight gained
opposite
545
When choosing an antigen for vaccine production, what are the two aspects to consider?
immunogenicity and toxicity
546
The large subunit of the bacterial ribosome has a sedimentation coefficient of what?
50 Svedberg (S)
547
What is RT-PCR?
a molecular technique that measures mRNA levels of specific protein
548
What is Western blotting?
a technique that measures the translational levels of a protein
549
What are the three amino acids that are phosphorylated in eukaryotes?
serine (S), threonine (T), and tyrosine (Y)
550
True or False: Both the active and inactive X chromosomes replicate
True, both the active and inactive X chromosomes replicate
551
What chromosome is one of the last chromosomes to replicate?
the inactivated X chromosome
552
What is a negative control?
the group that is performed in the conditions that are not expected to give positive results
553
Osmoreceptors are activated by what?
the increase in osmolarity of the blood
554
The increase in osmolarity of the blood process triggers what?
the sensation of thirst
555
An amber codon is what kind of codon?
a stop codon
556
What is hybridization?
the annealing of two complementary nucleic acids
557
The presence of a particular messenger RNA within a specific cell type can be assessed by what?
hybridization to a complementary probe
558
RNA polymerase transcribes both exons and introns to form what?
pre-mRNA
559
During RNA processing, introns are removed by what process to yield mature mRNA?
splicing
560
Complementary DNA is generated from mature mRNA and [does or does not] contain introns
does not
561
What happens during mitotic prophase?
the parent cell nuclear envelope breaks down and chromosomes condense
562
Nuclear envelopes reform around each chromosome set during what phase?
telophase
563
Cytokinesis forms what?
two identical daughter cells
564
Plasma membranes of cells are described as what?
a fluid mosaic composed mainly of a phospholipid bilayer with other components interspersed throughout
565
Because interactions between hydrophobic and hydrophilic molecules are energetically unfavorable, hydrophilic molecules require what to cross the interior hydrophobic portion of the plasma membrane?
transport proteins
566
Where do both eukaryotic and prokaryotic cells carry out glycolysis?
in the cytoplasm
567
In eukaryotes, pyruvate molecules resulting from glycolysis are transported into where?
the mitochondria
568
Prokaryotic cells carry out the Krebs cycle in their cytoplasm and have ETC proteins embedded where?
in the outer plasma membrane
569
Eukaryotic and prokaryotic cells are surrounded by what?
an outer plasma membrane
570
Viruses are surrounded only by a _______ ______ or have an outer _____________ _______ surrounding this protein coat
protein capsid; phospholipid bilayer
571
W
572
What is a constitutively active gene?
a gene that is transcribed at a relatively constant rate regardless of current cell conditions
573
During periods of fasting, what organ helps maintain blood glucose levels?
the liver
574
How does the liver initially synthesize glucose?
by degrading glycogen
575
After glycogen stores are depleted in prolonged fasting, what process is upregulated?
gluconeogenesis
576
In the fasting state, the liver [upregulates or downregulates] key enzymes of glycolysis and [upregulates or downregulates] enzymes of gluconeogenesis
downregulates; upregulates
577
Electrical synapses transfer information from one cell to another using what?
passive ionic current flow through gap junctions
578
Chemical synapses use what to transfer information?
neurotransmitters
579
The process of chemical synapses is [slower or faster] than electrical synapses
slower
580
Receptors can be classified as what?
either ligand-gated ion channels or G protein-coupled receptors
581
At inhibitory synapses, pre-synaptic release neurotransmitters that cause what?
either an influx of negative ions into the post-synpatic neuron or an efflux of positive ions out of the post-synaptic neuron
582
An influx of negative ions into the post-synpatic neuron or an efflux of positive ions out of the post-synaptic neuron causes what?
hyperpolarization of the membrane potential
583
Peptide hormones are [hydrophobic or hydrophilic] and [are soluble in blood or are not soluble in blood]
hydrophilic; are soluble in blood
584
Hormones that must bind transport proteins are called what?
steroid proteins
585
True or False: Steroid proteins are lipophilic
True
586
Gonadotropin-releasing hormone regulates pituitary gonadotropin secretion, which is part of what endocrine axis?
the reproductive axis
587
Apoptotic signaling most likely leads to what?
growth arrest
588
Inhibition of apoptosis is a characteristic of what?
cancer cells
589
The expression levels of tubulin is [stable or unstable] under most conditions
stable
590
What is the sequence of the HIF binding sequence that is palindromic?
CCCGGG
591
Succinate dehydrogenase is also known as what?
Complex II in the electron transport chain
592
Succinyl-CoA synthetase results in what?
the increased production of succinate
593
How are imprinted genes expressed?
they are expressed in a parent-specific manner
594
What does protein synthesis being under way when the radioactive amino acids were added infer?
that the N-terminal end and the middle part of the protein were already synthesized before the addition of the radioactive amino acids
595
RNA viruses require what to replicate themselves?
a type of transcriptase (reverse transcriptase)
596
In healthy individuals, what structure prevents the entry of large molecules, such as proteins, into the filtrate?
the glomerulus
597
Epithelial cells are specialized cells for what purpose and where are they present?
secretion and are present in the respiratory tract
598
Blocking the reuptake of serotonin into the presynaptic neurons would [increase or decrease] the amount of time that serotonin is available in the synaptic cleft to bind to postsynaptic neurons
increase
599
An excess of unabsorbed fats in the intestines inhibits what?
normal water and electrolyte absorption
600
Inhibition of normal water and electrolyte absorption results in what?
increased osmotic pressure and diarrhea
601
What is the function of osteoblasts?
to build and repair bone
602
What is the function of osteoclasts?
to break down bone
603
To increase calcium levels in the blood, osteoblast activity should be [increased or decreased] and osteoclast activity should be [increased or decreased] to release stored calcium from the bone to the bloodstream
decreased; increased
604
What is apoptosis?
the programmed and controlled death of aged, unnecessary, or damaged cells
605
Cancerous cells exhibit what?
rapid and uncontrolled cell proliferation
606
Rapid and uncontrolled cell proliferation exhibited by cancerous cells is caused by what?
cell growth that outpaces normal apoptosis or by dysfunction of the apoptotic process itself
607
True or False: Eukaryotic chromosomes have both protein-coding DNA and district noncoding regions
True
608
Noncoding regions of eukaryotic chromosomes include what?
the centromere and telomeres
609
Cell membranes are composed largely of what?
phospholipids
610
Phospholipids serve what function?
they act as a fluid that allows other membrane components such as transmembrane proteins, glycoproteins, cholesterol, and glycolipids to migrate through this enviornment laterally
611
The structure of the animal cell membrane is known as what?
the fluid mosaic model
612
What happens after the internalization of extracellular materials into vesicles?
the vesicles containing these materials become endosomes, which mature from an early stage to a late stage, ultimately becoming lysosomes
613
Endocytic cargo that does not enter alternative pathways and fails to escape from endosomes will end up where?
in the lysosome to be degraded
614
What are the two major branches of the nervous system?
the central and peripheral nervous systems
615
The peripheral nervous system can be further divided into what?
the sensory and motor divisions
616
The motor division of the peripheral nervous system is composed of what?
the somatic and autonomic nervous systems
617
The autonomic nervous system is divided into what branches?
the parasympathetic and sympathetic branches
618
Infusion of glucagon will result in what?
mobilization of endogenous glucose storage
619
What is the name of the enzyme that catalyzes the rate-limiting step in glycogen breakdown?
glycogen phosphorylase
