bio Flashcards
A ribonucleoside has a ______ and a ________
hydroxyl group on the 2’ and 3’ carbons; purine
How many nitrogens are in an imidazole group?
2
Which of the following structures represents histidine with a protonated side chain?
Which of the following structures is a ribonucleoside?
The reaction in which histidine is converted to histamine is catalyzed by what enzyme?
histidine decarboxylase
What nitrogenous bases contain an imidazole group?
Adenine and Guanine
The alpha-helical structure of a protein is held together by what type of bond?
Hydrogen bonding between carbonyl oxygen and amino hydrogen atoms
Triacylglycerols consist of what?
Three fatty acid subunits connected to a three-carbon glycerol backbone
This molecule is classified as a:
deoxyribonucleotide
What enzyme unwinds the DNA helix and separates the strands?
helicase
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?
DNA polymerase
What enzyme synthesizes a short RNA primer that is used as the starting point for the synthesis of a new strand of DNA?
Primase
Increased molecular length and bulkiness would generate _____ ________
steric hindrance
complementary strands are always synthesized in _______ directions
opposite
What is the function of DNA polymerase α?
initiates synthesis in eukaryotes
What is the function of DNA polymerase δ?
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
Examples of post-transcriptional modification include ________, ________, and ________
addition of a 5’ cap (specifically, a 7-methylguanylate cap), addition of a 3’ poly-A tail, and splicing
What is the start codon?
AUG
What are the three stop codons?
UGA, UAA, and UAG
What enzyme possesses a 3’-to-5’ exonuclease activity?
DNA polymerase
What is incomplete penetrance?
clinical symptoms (phenotype) are not always present in individuals who have the disease-causing mutation (genotype)
A test cross crosses the organism in question with an organism that is ________ for the ________ trait
homzygous; recessive
Diseases with high penetrance show what?
a high correlation between individuals that have the disease genotype and individuals who exhibit the signs and symptoms of the disease
Define the relationship between genetic linkage and the physical locations of two genes on the same chromosome
Genes that are physically far apart are less likely to be linked
What are the two equations for Hardy-Weinberg equilibrium?
- p² + 2pq + q² = 1 2. p+q = 1
p² and q² correspond to ________ individuals for p and q, respectively
homozygous
The 2pq term gives the frequency of _________
heterozygotes
__________ 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
The following structure depicts what?
cytosine
The following structure shows what?
addition of a methyl at C5
Transcription of structural lac genes takes place so the bacterium can metabolize the lactose sugar when lactose is [present or absent]
present
Allolactose binds to _______, causing it to dissociate from _______ region, freeing up the _______ region for transcription to take place
repressor; operator; operator
cDNA is reverse transcribed from the associated ____ molecule
mRNA
cDNA lacks ______
introns
cDNA is named for being ____________ to ____
complementary; mRNA
In an electrolytic cell, the anode is _______ & the cathode is _______
positive; negative
Sanger sequencing involves the use of _______________
dideoxynucleotides
What are dideoxynucleotides?
Nucleotides that lack an -OH group on both the 2’ and 3’ carbons
The highest-temperature step of a PCR reaction is the __________ step
denaturation
What is the denaturation step?
the step in which the reaction mixture is heated to around 95°C
Which cells make myelin in the CNS?
oligodendrocytes
Which cells make myelin in the PNS?
Schwann cells
What are the resident macrophages of the central nervous system called?
microglia
_____ are functional groups in which a carbonyl carbon is attached to another –OR group
Esters
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
Action potentials are what kind of phenomena?
All-or-nothing
The extracellular concentration of sodium ions is [greater or less] than the intracellular concentration
greater
______ ______ and ________ can affect gene expression
steroid hormones; methylation
______ ________ & _________ affect gene expression
steroid hormones; methylation
______ ________ bind with nuclear receptors that regulate expression through transcription factors
steroid hormones
__________ is a DNA-level covalent modification that is an example of epigenetics
Methylation
______ ________ bind to membrane receptors and trigger intracellular signaling cascades that dramatically impact cellular activity
peptide hormones
At the peak of an action potential, the membrane potential of the neuron is approximately ___ mV
+40
______ ceases to flow into the cell, while voltage-gated ________ channels open to allow ________ to flow out of the cell
sodium; potassium; potassium
What is the function of the basal ganglia?
controls fine motor movements
What is the function of the inferior colliculus?
transmits signals to the medial geniculate nucleus located within the thalamus
What is hyperpolarization?
a state in which the membrane potential is more negative than its resting value
when ________ ions are positive, their exit from the cell would make its interior more ________
potassium; negative
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
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
What is the role of LH in males?
LH binds to its receptors on Leydig cells, stimulating testosterone synthesis and secretion
A paracrine agent acts on what?
nearby cells
Autocrine agents act on what?
the cell that secreted them
Exocrine activity involves what?
the secretion of products through ducts
The thyroid-stimulating hormone is secreted by one gland?
anterior pituitary gland
TSH acts on the thyroid gland to promote the secretion of which two hormones?
thyroxine (T4) and triiodothyronine (T3)
What is the function of thyroxine (T4) and triiodothyronine (T3) hormones?
increase the metabolic rate of nearly every cell in the body
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
The adrenal mineralocorticoid promotes what in the presence of ADH?
water retention
Calcium ions, cAMP, and cGMP are all common ______ __________
second messengers
True or False: ATP is considered a second messenger
False
Insulin is produced in what kinds of cells?
ꞵ cells
Glucagon is produced in what kinds of cells?
ɑ cells
Somatostatin is produced in what kinds of cells?
delta cells
Epsilon cells produce what hormone?
ghrelin
Corticotropin-releasing hormone (CRH) is secreted by what structure?
hypothalamus
Adrenocorticotropic hormone (ACTH) is released by what gland?
anterior pituitary gland
What is the function of ACTH?
acts on the adrenal cortex to release cortisol
Name the molecule corresponding to this structure
estradiol
·O₂⁻, ·OH, & H₂O₂ are all examples of what?
reactive oxygen species
Vitamin E is an ___________
antioxidant
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
What are the seven steps of the ejaculatory pathway of sperm?
Seminiferous tubules, epididymis, vas deferens, ejaculatory ducts, urethra, penis (think: SEVE(n) UP)
Ovulation in which diploid primary oocytes mature into haploid secondary oocytes occurs when?
after puberty
The variability of the menstrual cycle is due to what phase?
follicular phase
What is another word for the follicular phase?
proliferative phase
The luteal phase lasts for how many days in the menstrual cycle?
14 days
What is another word for the luteal phase?
the secretory phase
What is the order of the stages of embryonic development from earliest to latest?
Morula, blastula, gastrula, neurulation
What hormone mimics LH and maintains the corpus luteum to maintain estrogen and progesterone levels?
Human chorionic gonadotropin (hCG)
hCG is what kind of hormone?
peptide hormone
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
After gas exchange in the tissues, blood typically has a higher ______ ________ content, a lower ______ content, and a lower __
carbon dioxide; oxygen; pH
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
What blood vessels return oxygenated blood to the heart?
pulmonary veins
What structures provide electrical conduction to the ventricles?
Purkinje fibers
What is the name of the hormone released from blood platelets?
thromboxane
What is the name of the enzyme in blood plasma that causes the clotting of blood by converting fibrinogen to fibrin?
thrombin
Active exhalation involves contraction of what muscles?
internal intercostal muscles
Contraction of the diaphragm is associated with [inhalation or exhalation]?
inhalation
What is residual volume?
volume of air remaining in the lungs after an individual has exhaled as much as possible
How does the epiglottis protect the lungs?
closes while eating to protect the lungs from swallowed objects
Where is surfactant found and function does it serve?
in the alveoli and serves to reduce surface tension
What cells produce mucus?
goblet cells
Hyperventilation can markedly [increase or decrease] the amount of carbon dioxide in the blood
decrease
What kinds of receptors stimulate ventilation in response to increased arterial carbon dioxide levels?
carbon dioxide-sensing chemoreceptors
What form of transport is used to exchange gases between the alveoli and the capillaries?
simple diffusion
Individuals can only receive blood if [statement]
it does not contain antigens that the recipient makes antibodies against
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
The fluid movement into the Bowman’s space is [positive or negative]
positive
The fluid movement into the glomerular capillary is [positive or negative]
negative
What part of the nephron accounts for the majority of transport along the nephron?
the proximal tubule
The descending loop of Henle only allows for [passive or active] reabsorption of water
passive
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
__% of our sample values to fall within 1 standard deviation of the population mean
68
__% would fall within 2 standard deviations
95
__% of the sample values will be within 3 standard deviations of the population mean
99.7
What is oncotic pressure?
a form of osmotic pressure exerted by proteins in a blood vessel’s plasma
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%)
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
What is the function of the gallbladder?
releases stored bile into the small intestine to help emulsify fats
___________ are broken down in the small intestine by enzymes known as _______________
disaccharides; disaccharidases
The pancreas is the source of the zymogen form of ______, a ________
trypsin; protease
Starch is partially digested in the mouth by what enzyme?
salivary amylase
What organ is typically the site of the absorption of significant amounts of water into the body?
large intestine
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
Vasopressin activity results in what?
retention of water via reabsorption in the collecting duct of the nephron
A vasopressin receptor antagonist [increases or decreases] water retention, & [increases or reduces] blood volume
decreases; reduces
What is the function of the proximal convoluted tubule?
the site of major reabsorption and secretion that is largely driven by sodium transport
What is the function of the distal convoluted tubule?
involved with hormone-controlled reabsorption and secretion
What is the function of the Loop of Henle?
create an osmotic gradient
What is the function of the collecting duct?
create a concentration of urine
What sphincter is composed of skeletal muscle and is under voluntary control?
external anal sphincter
What sphincter (there are 2 names) separates the esophagus from the stomach and is under involuntary control?
the gastroesophageal sphincter or the cardiac sphincter
What sphincter separates the stomach from the small intestine and is involuntary?
the pyloric sphincter
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
True or False: Ketones are normally found in urine
False, ketones are not normally found in urine
The presence of ketones in urine is associated with what condition?
diabetes
Immunosuppression [increases or decreases] the risk of cancer
increases
What is the variable region?
the amino acid sequence that is complementary to the antigenic sequence
Antigens bind to the variable region through what kinds of interactions?
noncovalent interactions
The blood-brain barrier is formed by what?
capillary endothelial cells
What are tight junctions?
closely associated regions of adjacent cells that form a virtually impermeable barrier to fluid
True or False: Iron is present in carbonic anhydrase
False, iron is not present in carbonic anhydrase
What is carbonic anhydrase?
a metalloenzyme that catalyzes the reversible reaction between carbon dioxide and water
The active site of carbonic anhydrase contains a ____ molecule
zinc
Respectively, labels A, B, and C refer to
the renal medulla, the renal cortex, and a ureter
What kind of selection occurs when the population’s alleles are seen to favor more extreme phenotypes over time?
disruptive selection
What are centromeres?
heterochromatin-based regions of DNA that assist in the connection of sister chromatids
What is transformation?
taking up extraneous information from the environment
________ are used in lab settings to incorporate genes of interest into certain cells.
Plasmids
What is hyperpolarization?
when the neuron’s potential is dropping to a more negative value
What is hyperpolarization?
when the neuron’s potential is dropping to a more negative value
What is anterior-posterior patterning?
changing the poles or zone of polarizing activity
What is the function of limb-specific transcription factors?
activate the transcription of specific genes to initiate differentiation
What is the function of limb-specific transcription factors?
activate the transcription of specific genes to initiate differentiation
An embryo becomes a fetus by the ___ week of development
9th
The region marked 2 corresponds to what part of the antibody?
the antigen-binding domain or variable domain
What purpose does the variable domain serve?
allows antibodies to recognize very specific antigens
What purpose does the variable domain serve?
allows antibodies to recognize very specific antigens
Carbon dioxide is a ________ of hemoglobin that binds to the active heme group
substrate
Hemoglobin is an iron-containing _____________
metalloprotein
Circular loops or linear strands of ssDNA pertain to what organisms?
viruses
Linear strands of dsDNA pertain to what organisms?
humans
Circular loops of dsDNA pertain to what organisms?
bacteria
True or False: Erythrocytes are anucleate & incapable of synthesizing new proteins
True
True or False: Erythrocytes are able to produce MHC
False, erythrocytes are unable to produce MHC and do not express it under any circumstances
What happens in the first reaction of integration?
integrase cleaves a dinucleotide from the 3’ end of a strand of viral DNA
Cleaving a dinucleotide from the 3’ end of a strand of viral DNA involves the cleavage of a ___ bond
P-O
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
What is the average molecular weight of an amino acid?
110 Da
What is the average molecular weight of an amino acid?
110 Da
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
What is the consequence of using a denaturing agent?
disrupts the interactions between monomers
What is the consequence of using a reducing agent?
disrupts any disulfide bonds
Na⁺ reabsorption is of utmost importance to the function of what organ?
the loop of Henle
Na⁺ reabsorption is of utmost importance to the function of what organ?
the loop of Henle
The loop of Henle is where…
Na⁺ is reabsorbed from the filtrate moving through the nephron
What causes the depolarization of the neuron that occurs during the action potential?
the massive influx of sodium through voltage gated ion channels
Glycolysis produces ___ ATP molecules per glucose molecule
2
Glycolysis produces ___ ATP molecules per glucose molecule
2
How many Na⁺ molecules are extruded for each ATP molecule utilized by the sodium pump?
3 Na⁺ molecules
The protection of glucose in this harsh environment is due to what?
its effects on the diffusion of water
Hyperglycemia normally elicits [insulin or glucagon] secretion
insulin
[Glucagon or Insulin] secretion is suppressed by hyperglycemia
Glucagon
What feature of RNA makes RNA more reactive and unstable than its DNA counterparts?
the presence of a 2’ hydroxyl group on ribose
What feature of RNA makes RNA more reactive and unstable than its DNA counterparts?
the presence of a 2’ hydroxyl group on ribose
What is the typical resting potential of a neuron?
-45 mV
What is the typical resting potential of a neuron?
-45 mV
True or False: Prokaryotic translation does rely on the presence of several release factors
True
What release factor do eukaryotes need?
eukaryotic translation termination factor 1 (eRF1)
Protozoans are [eukaryotic or prokaryotic] organisms
eukaryotic
The cardiac muscle tissue has an action potential with a “_______” in its depolarization whereas the skeletal muscle tissue does not have a “_______.”
plateau; plateau
Repolarization is delayed due to what?
the action of slow-to-open voltage gated Ca2+ channels
the opening of K+ channels in skeletal muscle tissue is able to [slowly or rapidly] repolarize the cell
rapidly
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
What are restriction endonucleases?
enzymes that cut DNA at specific sites
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
The mesodermal layer gives rise to what three structures?
the skeletal system, the cardiovascular system, and the kidneys
When traveling from the cortex towards the inside of the body or the medulla, the solute concentration [increases or decreases]
increases
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
What types of cells should have the highest concentration of actin and myosin?
muscle cells
What types of cells should have the highest concentration of actin and myosin?
muscle cells
The ______ is the area of the nucleus where the genes that code for ribosomal RNA (rRNA) are transcribed
nucleolus
What is one of the functions of the liver?
drug detoxification
Stabilizing selection generally results from what?
forces favoring moderate phenotypes over extreme ones
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
Glucagon increases gluconeogenesis in the _____ and _______ only
liver; kidneys
Between meals, glucagon stimulates enzymes in the liver to break down _______ ______ so that glucose can be released into the bloodstream
glycogen stores
What is the function of aldosterone?
causes increased absorption of sodium and water
True or False: Aldosterone is a fast-acting hormone
False, aldosterone is not a fast-acting hormone
Vasopressin is also known as what?
ADH
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
The endoderm gives rise to what?
linings of internal organs (stomach, lungs, intestines, etc.)
What structures differentiate from the ectoderm?
epidermis, nervous system, eye lens, and hair
What structures differentiate from the mesoderm?
muscle, cardiac and skeletal systems, blood, heart, and spleen
The pulmonary veins are adjacent to what structure?
the left atrium
Pulmonary veins receive __________ blood from lungs and carry it back to the _____
oxygenated; heart
RNA pol I transcribes certain genes into what type of RNA molecule?
rRNA
What is lineage potential?
the ability to differentiate into many cell types
What is lineage potential?
the ability to differentiate into many cell types
As pluripotent cells develop into multipotent cells, they express a [greater, equal, or smaller] percentage of lineage-specific genes due to specialization
greater
What is one of the mechanisms used to “turn off” genes not related to newly specialized cells?
DNA methylation
In eukaryotes, dsDNA is wrapped around proteins known as what?
histones
A DNA-histone subunit is termed a __________
nucleosome
Chromatin represents what?
fully packed DNA
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
The term, “wild type,” refers to what?
traits an animal typically possesses when found in nature
____ ____ usually refers to a dominant trait but not always
wild type
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
What structure connects the esophagus to the stomach?
the cardiac sphincter
Dyneins carry cargo towards the [ends or center] of the cell
center
Where is the microtubule organizing center (MTOC) located?
close to the center of the cell
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
Kinesins travel toward the [positive or negative] ends of microtubules
positive
What is the likelihood of independent assortment for genes on different chromosomes?
50%
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
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
The daughter cells that are cast off with little cytoplasm are called what?
polar bodies
An antisense drug works to prevent what?
the expression of undesirable genes
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
The coordination of cell differentiation during development is extremely sensitive to what?
the timing of mRNA turnover
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
What is myoglobin?
the substance that holds oxygen in the muscles and organs
During anaphase of mitosis, sister chromatids are pulled apart at the ____________, each becoming an independent chromosome in the two diploid daughter cells
centromeres
What happens during anaphase I of meiosis I?
homologous pairs of chromosomes are separated into two daughter cells
The centromere is split and the sister chromatids separate during what phase of meiosis II?
anaphase II
Mammalian skin is involved with what three functions?
touch sensation, protection from disease, and protection against internal injury
Within a sarcomere, the microfilament length remains ______
stable
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
To retain a stable length, both ends of the microfilament must be
capped
What are cytochalasins?
drugs that inhibit the growth of microfilaments
E. coli bacteria is a species common to what anatomical structure?
colon
The _______ is continuous with the _____ so that bacteria can move between these two structures
appendix; colon
A reducing agent is used during SDS-PAGE for what purpose?
to cleave disulfide bonds
Disulfide bonds hold what?
two separate subunits of different masses together
True or False: Phosphodiester bonds contribute to the stabilization of protein structure
False, phosphodiester bonds do not contribute to the stabilization of protein structure
____________ _____ link adjacent nucleotides in DNA
Phosphodiester bonds
What type of inhibitors do not alter the slope of the Lineweaver–Burk plot, which is equal KM/Vmax?
uncompetitive inhibitors
Uncompetitive inhibitors bind their target enzymes only when what?
the substrate is first bound to the enzyme
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
What is the glomerulus?
a tuft of capillaries that bulges into the capsular space, which is a potential space lined with simple squamous epithelium
Fluid is expressed from the blood across the _________ ___________
capillary endothelium
What is the pathway of fluid through capillary endothelium?
capsular space → kidney tubule → proximal tubule → U-shaped loop of Henle → distal tubule
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
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
Vasoconstriction, the narrowing of a vessel, restricts blood flow to an organ and can [increase or decrease] blood pressure
increase
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
What are mutations?
heritable changes in the sequence of the nucleic acid component of chromosomes
Mutations that lead to unregulated cellular growth can lead to what?
cancer
Secondary spermatocytes are the products of meiosis I, where [diploid or haploid] cells are first formed
haploid
Erection is triggered by [sympathetic or parasympathetic] nervous stimulation
sympathetic
The ectoderm produces what four anatomical structures?
epidermis, nervous system, eye lens, and hair
Veins contain a layer of ______ muscle in their walls
smooth
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
Homologous chromosomes separate during anaphase of meiosis I, producing cells that are [diploid or haploid]
haploid
Stimulation of oxytocin receptors located in the uterine wall increases ________ ___________, which causes increased ________ _______ during subsequent contractions
uterine elasticity; uterine stretch
Glucagon stimulates ________________ in liver cells so that glucose can be made from non-sugar substrates
gluconeogenesis
The H zone refers to what?
the non-overlapping area between thin filaments in the center of the sarcomere
True or False: Thin and thick filaments slide relative to one another
True, thin and thick filaments slide relative to one another
The Z line is the name given to what?
junction or “border” at either end of the sarcomere
The Z line is __________ to the direction of contraction
orthogonal
Antibodies are recognized based upon their _____ ______
heavy chains
Regions 1,3, and 4 refer to what?
heavy chains
Heavy chains are part of the [variable or constant] region
constant
The Bohr effect characterizes what?
the inverse relationship between binding affinity and plasma carbon dioxide concentration
When the concentration of carbon dioxide increases, hemoglobin [increases or decreases] its affinity for oxygen
decreases
When the concentration of carbon dioxide decreases, hemoglobin [increases or decreases] its affinity for oxygen
increases
What is hybrid vigor?
a phenomenon in which the recessive gene persists due to the advantage of being heterozygous
Paracrine activity involves the secretion of what?
local signaling molecules known as paracrine factors diffuse to nearby target cells
What is the role of the wall of the artery?
acts as a semipermeable membrane setting up the conditions needed for osmosis to occur
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
The liver can partially regenerate after illness or damage through what process?
mitosis
Mitosis is the process whereby [human body cells or gametes] reproduce
human body cells
The ability to produce ATP via ATP synthase is common to both __________ and _____ cells
bacterial; human
Where does ATP synthesis take place in bacterial cells?
the plasma membrane
Where does ATP synthesis take place in human cells?
inner mitochondrial membrane
Most bacterial chromosomes are ________ whereas human chromosomes are ______
circular; linear
Work is equal to what?
the product of the force applied to an object and the distance over which the object is moved
What is convergent evolution?
a process whereby distantly related organisms independently evolve similar traits to adapt to similar needs
Gonadotropin-releasing hormone regulates _________ ____________ (luteinizing hormone and follicle-stimulating hormone) secretion
pituitary gonadotropin
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
Inhibition of apoptosis is a characteristic of what types of cells?
cancer cells
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
Na⁺K⁺+ ATPase is an example of what type of membrane transport?
primary active transport
The autonomic nervous system is part of the [central or peripheral] nervous system
peripheral
The adrenal medulla secretes what two hormones in response to short-term stress?
epinephrine and norepinephrine
Reactions to short-term stress are mediated by the ____________ branch of the autonomic nervous system
sympathetic
Osmotic pressure is [directly or indirectly] proportional to solute concentration
directly
Imprinted genes are expressed in what kind of manner?
parent-specific manner
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
RNA viruses require what type of enzyme to replicate themselves?
transcriptase
The structure of the glomerular capillaries serves what function?
to prevent the entry of large molecules, such as proteins, into the filtrate
What are epithelial cells and where are they found?
specialized cells for secretion and are found in the respiratory tract
How is serotonin removed from the synaptic space?
by transport of released serotonin back into the presynaptic terminal
Transport of released serotonin back into the presynaptic terminal, an action that _____ block
SSRIs
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
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
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
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
The sympathetic nervous system directly inhibits what two processes?
peristalsis and secretion of digestive enzymes
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
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
What is triggered when an action potential reaches a nerve terminal?
opening of Ca+ channels in the neuronal membrane
Because the extracellular concentration of Ca+ is greater than the intracellular Ca+ concentration, Ca+ flows [into or out of] the nerve terminal
into
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
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
Blood flows from where to where to where?
arteries to capillaries and then to veins
As molecular weight increases, the rate of filtration is expected to [increase or decrease]
decrease
Uracil is a component of what molecule?
RNA
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
What is a byproduct of the metabolism of the amino acids from protein?
nitrogen
What is the reason animals have kidneys?
to provide a way of eliminating nitrogenous waste products
True or False: The diaphragm relaxes during inspiration
False, the diaphragm does not relax during inspiration
Elevation of the rib cage serves what function?
increases the volume inside the chest cavity
Reduction of pressure inside the pleural cavity causes what?
air to move into the lungs
Contraction of the external intercostal rib muscles serves what function?
helps the chest expand
How does atropine prevent acetylcholine from exerting its effect?
by preventing its binding to the acetylcholine receptor
What autonomic nerve fibers innervate the heart to slow it down?
the parasympathetic motor fibers of the vagus nerve
Multiple pathways to ganglia lead to what?
more rapid response of the sympathetic system
Hydrolysis of acetylcholine results in [increased or decreased] acetylcholine levels
increased
What is the name of the enzyme that breaks down acetylcholine?
acetylcholinesterase
What is the purpose of removing acetylcholine from the synapse?
to make sure the neurotransmitter can no longer activate its receptor
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
Eukaryotic cell membrane is made up of what?
a bilayer of amphipathic lipids with associated proteins
What is one of the characteristics of viruses?
they are obligate intracellular parasites
Viruses are unable to reproduce without the aid of what?
the host cell’s metabolic machinery
How do viruses make more virus particles?
by taking advantage of the elaborate intracellular mechanisms of the host cell
True or False: Viruses can be grown in tissue culture
True
Transcription is _______
copying
Translation is ________ ___ ________
changing the language
How do viruses make proteins?
by translating their specific RNAs into protein
The initial source for energy replacement is from hepatic glycogen indicating upregulation of what process?
glycogen breakdown (glycogenolysis)
After hepatic glycogen stores are exhausted the glucose pool must be replenished from non-carbohydrate sources implying upregulation of what pathway?
the gluconeogenic pathway
What three compounds are used in gluconeogenesis?
lactate, oxaloacetate, and α-ketoglutarate
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
Activation of the G protein promotes what?
the dissociation of bound GDP and its exchange for GTP on the α subunit
Exposure to high glucose levels results in [elevated or lowered] levels of circulating insulin which prevents mobilization of endogenous glucose storage
elevated
What is the technique used to detect a particular sequence in a sample of RNA?
Northern blotting
What is the technique used to detect a particular sequence in a sample of DNA?
Southern blotting
Parathyroid hormone promotes what function?
the breakdown of bone tissue
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
Parathyroid hormone will [increase or decrease] the number of osteoclasts
increase
Calcitonin reduces ____ __________
bone resorption
When does bone resorption occur?
when the level of calcium in the blood plasma is low
Removal of the parathyroid gland would lead to ____________, a condition of low blood calcium, resulting from the lack of parathyroid hormone
hypocalcemia
What is one of the key factors that determines a species?
the ability to successfully breed and produce fertile offspring
An aldosterone deficiency would result in [higher or lower] Na+ reabsorption into the bloodstream
lower
Decreased blood volume would result in [increased or decreased] blood pressure
decreased
The double stranded daughter DNA molecule would be an _____ _________ of the parent molecule
exact duplicate
The nitrogenous base, uracil, combined with the sugar ribose and phosphate makes up what nucleotide?
uridine
Uridine is found in ___, but not in ___
RNA; DNA
Nervous tissue arises developmentally from what germ layer?
ectoderm
Circulatory, bone, and dermal tissue all arise from what germ layer?
mesoderm
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
Any disruption of mitochondria is likely to [increase or decrease] ATP production since they are a major cellular source of that molecule
decrease
What would occupy the active site on the ATP synthase molecule?
ATP or precursor molecules such as phosphate and ADP
What would disrupt the electrochemical gradient responsible for the necessary flow of protons?
an influx of another positively charged ion
Males specifically pass down their own chromosomes to their [sons or daughters]
daughters
In order to regulate blood glucose levels, glycogen is made, stored, and broken down in where?
the liver
An increase in acetylcholine receptors on the postsynaptic membrane would [enhance or diminish] transmission
enhance
What types of muscles contain striated muscle fibers?
skeletal and cardiac muscles
True or False: Cells progressively differentiate to achieve their final specification
True
What is the name of the hormone responsible for triggering ovulation?
luteinizing hormone
When vasodilation occurs, the walls of blood vessels [contract or relax], allowing [more or less] blood to enter the area
relax; more
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
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
How may the human body gain heat?
by absorbing radiation from the sun
The major dissolved components of bile are breakdown products of __________ such as bilirubin and bile salts
hemoglobin
Bile salts allow dietary fats (and oils) to form what?
an emulsion of tiny droplets dispersed in the digestive juices
How does the dispersion of fats in the aqueous digestive juices and aid digestion?
by making them available to digestive enzymes
Histones come together with DNA to form what?
nucleosomes
What are nucleosomes?
the bead-like, primary structural elements of chromatin
Long bones grow through what process?
endochondral ossification
Endochondral ossification requires what?
cartilaginous growth plates at the ends of long bones that thicken as cartilage and later become ossified
In a eukaryotic cell, transcription occurs where?
in the nucleus
Sweat glands secrete onto the surface of the skin through what?
channels continuous with the epidermis
How do channels continuous with the epidermis prevent water loss?
by isolating the water-permeable, sweat-secreting cells from dry surface air
What are the openings of the sweat glands on to the surface of the epidermis called?
pores
Phosphatases are responsible for what?
cleavage of phosphate bonds utilizing water to remove a molecule of inorganic phosphate
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
True or False: Antibodies are often generated when an organism cross react with other organisms
True
The lack of what mechanism is a limitation for bacteria
the lack of a mechanism splicing introns
Organic acids can fully dissociate when the pH of blood is [higher or lower] than the pKa of organic acids
higher
What is cytochrome c?
a heme protein that cycles between a ferrous (Fe⁺²) and ferric (Fe⁺³) state during oxidative phosphorylation
How many electrons are transferred in cytochrome c in oxidative phosphorylation?
one electron
The best primers for PCR have a high __ content and __ bases in 5′ and 3′
GC; CG
What is nondisjunction?
the process when paired chromosomes or duplicated chromosomes fail to separate and segregate in two distinct daughter cells
What is an inherent property of transport proteins?
transport affinity for substrates
The metabolic rate is an internal variable that will help define what?
the capability of an organism to withstand long periods of nutrient deprivation
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
Cells produce how many molecules of ATP in aerobic conditions?
30 molecules of ATP
Cells produce how many molecules of ATP in anaerobic conditions?
2 molecules of ATP
Actin is a what?
microfilament
Intermediate filaments serve what function?
mostly provide mechanical support to the plasma membrane and position the nucleus in the cell
____________ are the site of ATP production
Mitochondria
The head of a fatty acid is what?
-CO₂⁻-, a carboxyl group
HCO₃⁻ is derived from the dissociation of _____, which is made by _______ _________
H₂CO₃; carbonic anhydrase
By moving one-by-one along the capillary, there is [more or less] RBC surface that is available for gas exchange
more
What enzymes cleave within DNA nucleotide chains?
endonucleases
What enzymes cleave the last nucleotides on either side of DNA nucleotide chains?
exonucleases
What enzymes cleave bonds in RNA nucleotide chains?
ribonucleases
Cleavage of peptide bonds is catalyzed by what enzyme?
protease
Threonine (Thr) is a _____ and ___________ amino acid
polar; hydrophilic
What are the four stages of the human female life cycle in order?
fertilization → birth → puberty → menopause
The reproductive tract, respiratory tract, and gastrointestinal tract all contain what?
an element of mucosa
Glucocorticoid secretion by the adrenal medulla [increases or decreases] with stress
increases
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
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
What is aldosterone?
a hormone released by the adrenal glands
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
Reduced flow of blood through the renal arteries due to the clamps would cause an [increase or decrease] in glomerular blood pressure
decrease
How do kidneys respond to a drop in glomerular blood pressure?
by activating the renin–angiotensin system of hormones
Enhanced activity of what types of muscles in blood vessels would cause vasoconstriction?
smooth muscles
What is the primary process that takes place in the colon?
absorption of water
What would happen if an ulcer penetrated the walls of the intestine?
the contents of the gastrointestinal tract would enter the peritoneal cavity
Antigens are carried on what?
the surface of cells
Adaptive radiation involves what?
the divergence of one species into multiple species over time
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
What causes the membrane potential to become more positive?
sodium ions moving into the neuron
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
High levels of blood calcium available for deposit into bone should [stimulate or inhibit] release of calcitonin
stimulate
What happens when glycerol reacts with three different fatty acids?
only carbon 2 in the resulting triacylglycerol is attached to four different groups
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
Solubility is determined by what?
Henry’s law
What is Henry’s law?
H=c/P
Cytochrome P450 acts as what?
monooxygenases
What are monooxygenases?
where an oxygen atom is inserted into a substrate (the drug of interest)
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
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
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
What is a mature ovum?
the female gamete that has completed meiosis and contains the haploid number of maternally derived chromosomes
What are spermatozoa?
the mature male gametes that contain the haploid number of paternally derived chromosomes
Phagocytosis requires what?
that the cell change shape dramatically as it surrounds and engulfs large extracellular particles
What are microtubules?
one of the cytoskeletal elements that help determine cell shape
Cell shape relies on the ability of what?
the microtubules to disassemble and reorganize
Where does glycolysis occur?
in the cytoplasm
Where does the citric acid cycle occur?
in the matrix of mitochondria
To compensate for the increased body temperature in a fever, skin capillaries [constrict or dilate] to dissipate heat through the skin
dilate
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
What characteristic do arteries, veins, and capillaries have in common?
they all possess an inner layer of endothelial cells
The pancreas produces several ___________ _______
proteolytic enzymes
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
What types of cells have one of the highest rates of mitosis among non-cancerous cells?
epithelial cells of the skin
The restriction point is a point in __ of the cell cycle, and after it is passed the cell is committed to division
G₁
The G₂ checkpoint checks for what?
DNA damage after DNA replication
What happens if damage is detected by the G₂ checkpoint?
“pauses” cell division until damage is repaired
Microtubules are responsible for what?
the movement of fully duplicated chromosomes away from each other from the metaphase plate
What is lymphoma?
a cancer that arises from cells that are part of the body’s immune system
[Males or Females] are much more likely to be affected by an X-linked disease
Males
Why are males more likely to be affected by an X-linked disease than females?
they only have one copy of the X chromosome
What are the 4 possible RNA bases?
A, G, C, and U
What are the 3 possible stop codons that do not code for amino acids?
UAA, UAG, and UGA
What is a genetic bottleneck?
a reduction in gene-pool diversity because of a sharp reduction in population size
What does p² represent?
the frequency of homozygous dominant individuals
What does 2pq represent?
the frequency of heterozygous individuals
What does q² represent?
the frequency of homozygous recessive individuals
What is sympatric speciation?
describes reproductive isolation that emerges when no physical barrier separates a population
What is directional selection?
where a more extreme phenotype is favored
Why does allopatric speciation occur?
because of physical barriers
Geographic isolation, separating the Asian and European samples, is a common cause of what?
allopatric speciation
When does leakage occur?
when genes from one species flow to another
Penetrance reflects what?
the proportion of individuals in a population who express a certain genotype
Expressiveness reflects what?
the strength with which the phenotype is expressed
The descending limb, extending from cortex into the salty medulla, is highly permeable to _____ but impermeable to ____
water; NaCl
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
Juxtamedullary nephrons have long loops of Henle extending deep into the salty medulla to [maximize or minimize] water reabsorption
maximize
Cortical nephrons have shorter loops of Henle extending shorter distances into the medulla, making them [more or less] efficient at water reabsorption
less
What happens on binding antigens presented by B lymphocytes?
helper T cells release cytokines that stimulate B lymphocyte proliferation
What cells respond to antigens by releasing toxins that induce apoptosis (cell death) in nearby infected cells?
natural killer & cytotoxic T cells
What happens during prophase?
chromatin condenses into distinct chromosomes and the nuclear envelope disintegrates
[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
What is phosphoglycerate mutase?
an enzyme that catalyzes the reversible conversion of 3-phosphoglycerate (3-PG) to 2-phosphoglycerate (2-PG)
Potassium (K⁺) leak channels help maintain the membrane potential by enabling what form of transport of K⁺ out of the cell?
passive transport
______ _____ pumps embedded in the outer membrane of neurons hydrolyze adenosine triphosphate to provide energy to transport molecules against their concentration gradient
active transport
Name the general steps involved during the life cycle in order
Attachment, viral genome entry, host genome degradation, synthesis, and release
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
Proteins with the shortest amino acid sequences have [lower or higher] molecular weights and migrate more [quickly or slowly] through the gel.
lower; quickly
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
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
When and how are euchromatin formed?
when histones are modified, often by acetylation of lysine residues
In DNA synthesis, the template strand is always ____________ to the new strand that is being synthesized
complementary
Systemic circuit distributes [oxygenated or deoxygenated] blood containing nutrients to all body tissues via [arteries or veins]
oxygenated; arteries
When oxygenated blood reaches the capillaries within the systematic tissues, it delivers __ and nutrients to the tissues and picks up ___
O₂; CO₂
Veins return the [oxygenated or deoxygenated] blood back to the ______ so it can enter the pulmonary circuit
deoxygenated; heart
Pulmonary circuit pumps [oxygenated or deoxygenated] blood through the pulmonary arteries to capillaries in the lungs to facilitate ___ _______
deoxygenated; gas exchange
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
What is the effect of calcitonin and how does it perform its function?
stimulates bone formation by increasing osteoblast activity and decreasing osteoclast activity
What are promoters?
upstream DNA sequences in the eukaryotic genome that bind with transcription factors
How does doxycycline function?
by competing for aminoacyl-tRNA for binding to A site of the 30S ribosome subunit
True or False: Testosterone is a peptide hormone
False, testosterone is a steroid hormone
As a hormone, how is testosterone transported?
throughout the body in the circulatory system
True or False: Testosterone must bind to a transport protein
True, testosterone must bind to a transport protein
Malate is reversibly oxidized by the microsomal enzyme ______ _____________, producing ____ and ____________
malate dehydrogenase; NADH; oxaloacetate
Isocitrate is formed from citrate by what enzyme?
aconitase
Isocitrate is catalyzed by __________ ____________, producing _____________ and ______ ________
isocitrate dehydrogenase; ɑ-ketoglutarate; carbon dioxide
What does a virus do to bacteria in the lytic phase?
a virus will infect and kill bacteria
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
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
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
What is the nuclear localization signal?
a sequence that tags the protein for it to be transported into the nucleus
What is the only step of cellular respiration where NAD⁺ is neither reduced to form NADH, nor is NADH oxidized to form NAD⁺?
chemiosmosis
The _________ _______ __ ___ __________ ____ is the last portion of the tubules where water reabsorption can occur
medullary portion of the collecting duct
Membrane depolarization is due to what?
the opening of Na⁺ channels
Membrane depolarization is a process that is [independent or dependent] from the Na⁺/K⁺ ATPase
independent
The restoration and maintenance of the resting potential relies on what?
Na⁺/K⁺ ATPase
Transcription factors and regulate the expression of other genes by binding to the promoter or the enhancer of the gene located on what?
DNA
In protein kinase enzymes, _____________ is the activating event
phosphorylation
What is the role of ABC transporter proteins?
to use ATP to actively transport molecules such as drugs out of the cell
What are lipid rafts?
cholesterol-rich domains within the membrane
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
___________ ___________ ________ will force filtrate from a capillary into Bowman’s capsule
glomerular capillary pressure
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
What is a direct consequence of protein degradation in muscles?
increased muscle weakness
Anaerobic metabolic pathways can produce energy [with or without] using oxygen by glycolysis
without
Microfilaments are composed of what?
actin
This is the structure of what molecule?
serine
True or False: Serine can be phosphorylated
True
A Southern blot uses what to differentiate between mutant and wild-type alleles?
a restriction digest
Palindromes are how many base pairs long?
4 to 6 base pairs
What is the recognition sequence for HindIII?
AAGCTT
True or False: The hypothalamus secretes ghrelin
False, the stomach and small intestine secrete ghrelin
The levels of circulating insulin will [increase or decrease] after a meal due to an increase in blood glucose levels
increase
Because of a feedback mechanism, the levels of circulating ghrelin are the [same or opposite] of the amount of weight gained
opposite
When choosing an antigen for vaccine production, what are the two aspects to consider?
immunogenicity and toxicity
The large subunit of the bacterial ribosome has a sedimentation coefficient of what?
50 Svedberg (S)
What is RT-PCR?
a molecular technique that measures mRNA levels of specific protein
What is Western blotting?
a technique that measures the translational levels of a protein
What are the three amino acids that are phosphorylated in eukaryotes?
serine (S), threonine (T), and tyrosine (Y)
True or False: Both the active and inactive X chromosomes replicate
True, both the active and inactive X chromosomes replicate
What chromosome is one of the last chromosomes to replicate?
the inactivated X chromosome
What is a negative control?
the group that is performed in the conditions that are not expected to give positive results
Osmoreceptors are activated by what?
the increase in osmolarity of the blood
The increase in osmolarity of the blood process triggers what?
the sensation of thirst
An amber codon is what kind of codon?
a stop codon
What is hybridization?
the annealing of two complementary nucleic acids
The presence of a particular messenger RNA within a specific cell type can be assessed by what?
hybridization to a complementary probe
RNA polymerase transcribes both exons and introns to form what?
pre-mRNA
During RNA processing, introns are removed by what process to yield mature mRNA?
splicing
Complementary DNA is generated from mature mRNA and [does or does not] contain introns
does not
What happens during mitotic prophase?
the parent cell nuclear envelope breaks down and chromosomes condense
Nuclear envelopes reform around each chromosome set during what phase?
telophase
Cytokinesis forms what?
two identical daughter cells
Plasma membranes of cells are described as what?
a fluid mosaic composed mainly of a phospholipid bilayer with other components interspersed throughout
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
Where do both eukaryotic and prokaryotic cells carry out glycolysis?
in the cytoplasm
In eukaryotes, pyruvate molecules resulting from glycolysis are transported into where?
the mitochondria
Prokaryotic cells carry out the Krebs cycle in their cytoplasm and have ETC proteins embedded where?
in the outer plasma membrane
Eukaryotic and prokaryotic cells are surrounded by what?
an outer plasma membrane
Viruses are surrounded only by a _______ ______ or have an outer _____________ _______ surrounding this protein coat
protein capsid; phospholipid bilayer
W
What is a constitutively active gene?
a gene that is transcribed at a relatively constant rate regardless of current cell conditions
During periods of fasting, what organ helps maintain blood glucose levels?
the liver
How does the liver initially synthesize glucose?
by degrading glycogen
After glycogen stores are depleted in prolonged fasting, what process is upregulated?
gluconeogenesis
In the fasting state, the liver [upregulates or downregulates] key enzymes of glycolysis and [upregulates or downregulates] enzymes of gluconeogenesis
downregulates; upregulates
Electrical synapses transfer information from one cell to another using what?
passive ionic current flow through gap junctions
Chemical synapses use what to transfer information?
neurotransmitters
The process of chemical synapses is [slower or faster] than electrical synapses
slower
Receptors can be classified as what?
either ligand-gated ion channels or G protein-coupled receptors
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
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
Peptide hormones are [hydrophobic or hydrophilic] and [are soluble in blood or are not soluble in blood]
hydrophilic; are soluble in blood
Hormones that must bind transport proteins are called what?
steroid proteins
True or False: Steroid proteins are lipophilic
True
Gonadotropin-releasing hormone regulates pituitary gonadotropin secretion, which is part of what endocrine axis?
the reproductive axis
Apoptotic signaling most likely leads to what?
growth arrest
Inhibition of apoptosis is a characteristic of what?
cancer cells
The expression levels of tubulin is [stable or unstable] under most conditions
stable
What is the sequence of the HIF binding sequence that is palindromic?
CCCGGG
Succinate dehydrogenase is also known as what?
Complex II in the electron transport chain
Succinyl-CoA synthetase results in what?
the increased production of succinate
How are imprinted genes expressed?
they are expressed in a parent-specific manner
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
RNA viruses require what to replicate themselves?
a type of transcriptase (reverse transcriptase)
In healthy individuals, what structure prevents the entry of large molecules, such as proteins, into the filtrate?
the glomerulus
Epithelial cells are specialized cells for what purpose and where are they present?
secretion and are present in the respiratory tract
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
An excess of unabsorbed fats in the intestines inhibits what?
normal water and electrolyte absorption
Inhibition of normal water and electrolyte absorption results in what?
increased osmotic pressure and diarrhea
What is the function of osteoblasts?
to build and repair bone
What is the function of osteoclasts?
to break down bone
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
What is apoptosis?
the programmed and controlled death of aged, unnecessary, or damaged cells
Cancerous cells exhibit what?
rapid and uncontrolled cell proliferation
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
True or False: Eukaryotic chromosomes have both protein-coding DNA and district noncoding regions
True
Noncoding regions of eukaryotic chromosomes include what?
the centromere and telomeres
Cell membranes are composed largely of what?
phospholipids
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
The structure of the animal cell membrane is known as what?
the fluid mosaic model
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
Endocytic cargo that does not enter alternative pathways and fails to escape from endosomes will end up where?
in the lysosome to be degraded
What are the two major branches of the nervous system?
the central and peripheral nervous systems
The peripheral nervous system can be further divided into what?
the sensory and motor divisions
The motor division of the peripheral nervous system is composed of what?
the somatic and autonomic nervous systems
The autonomic nervous system is divided into what branches?
the parasympathetic and sympathetic branches
Infusion of glucagon will result in what?
mobilization of endogenous glucose storage
What is the name of the enzyme that catalyzes the rate-limiting step in glycogen breakdown?
glycogen phosphorylase
