7C final
The release of neurotransmitter from the presynaptic cell is an example of: exocytosis. transcytosis. endocytosis. phagocytosis.
exocytosis. released to the exterior
Myosin is a motor protein that associates with: microtubules. intermediate filaments. microfilaments. vimentin.
microfilaments.
When a person has a few drinks containing alcohol, they often feel the need to urinate. This response suggests interplay between alcohol and antidiuretic hormone (ADH). Which of the following could explain how alcohol and ADH interact? (note: ADH causes a decrease in urine production) Alcohol facilitates the binding of ADH to receptors in the brain, so individuals "feel" the need to urinate. Alcohol decreases the release of ADH. Alcohol inhibits the binding of ADH to receptors in the brain, so individuals "feel" the need to urinate. Alcohol increases the release of ADH.
Alcohol decreases the release of ADH. Since ADH decreased the urine production, then decreasing the amount of ADH will help increase the urine production Almost like the ADH is an inhibitor for the urine production
Certain medications can cause potassium levels in the body to decrease. Which symptom would be consistent with a loss of potassium? All of these choices are correct. fatigue muscle weakness irregular heartbeat
All of these choices are correct.
Imagine that a student studies all night for an exam the next day. The student remembers (almost) everything for her test, but within a week she forgets most of what she studied. Why? New neural circuits were not formed (or strengthened) in the student's brain. All of these choices are correct. The student's short-term memories regarding the test material were not successfully transformed into long-term memories. The student has not studied the material she was tested on repeatedly.
All of these choices are correct.
econd messengers: are removed in order to terminate a cellular signaling response. play a role in activation of intracellular signal transduction. All of these choices are correct. are small intracellular molecules that participate in signal transduction. amplify the effects of the signal.
All of these choices are correct.
Many birth-control pills release a constant amount of synthetic estradiols and progesterone for 21 days, followed by 7 days when no hormones are ingested. Which of the following statements MOST accurately describes the effects of birth-control pills? Birth-control pills maintain constant levels of estrogens and/or progesterone so there is no surge in LH and ovulation does not occur. Birth-control pills maintain constant levels of estrogens and/or progesterones and mask the release of the oocyte from the follicle. Birth-control pills inhibit the development of the uterine lining so implantation of a fertilized oocyte cannot occur. The 7 days with no hormones does not allow a thick enough uterine lining to form so a fertilized oocyte cannot implant.
Birth-control pills maintain constant levels of estrogens and/or progesterone so there is no surge in LH and ovulation does not occur. The LH surge is what causes the egg to drop
Research suggests that learning may involve: Ca2+ influx into a postsynaptic cell, causing biochemical changes and enhanced response to stimulation. synaptic changes causing slower reuptake of neurotransmitter from the synaptic cleft. changes in action potential duration caused by blocking voltage-gated K+ channels. synaptic changes caused by decreasing the size of the synaptic cleft and increasing the effectiveness of neurotransmitter diffusion. strengthening the sodium-potassium pump.
Ca2+ influx into a postsynaptic cell, causing biochemical changes and enhanced response to stimulation.
If a mutation occurred in the cadherin gene so that the cytoplasmic domain no longer attached to the cytoskeleton, which of the following would occur? Cadherins in hemidesmosomes would no longer be anchored to intermediate filaments. Cadherins in desmosomes would no longer be anchored to microfilaments. Cadherins in desmosomes would no longer be anchored to intermediate filaments. Cadherins in adherens junctions would no longer be anchored to microtubules.
Cadherins in desmosomes would no longer be anchored to intermediate filaments.
All neurons have either a sensory or a motor function. True False
False
Given that most ligands form covalent bonds with their associated receptors, these complexes are more or less permanent and can only be broken through the hydrolysis of ATP. False True
False
The magnitude of the action potential is correlated with the strength of the stimulating input. True False
False
Which of the following are TRUE about the resting membrane potential? (Select all that apply.) It results from K+ ions diffusing out of the cell. It results from the sodium-potassium pump moving more Na+ ions out of the cell than K+ ions into the cell. It results from voltage-gated sodium channels remaining open for long periods of time.
It results from K+ ions diffusing out of the cell. It results from the sodium-potassium pump moving more Na+ ions out of the cell than K+ ions into the cell.
A key difference between hormonal regulation of the reproductive systems of males and females is that: LH and FSH are released only in males. LH and FSH are released only in females. LH is released continuously in males and FSH is released cyclically in females. LH is released in males and FSH is released in females. LH and FSH are released cyclically in females but nearly continuously in males.
LH and FSH are released cyclically in females but nearly continuously in males.
Some people have low levels of calcium circulating in the blood, a condition known as hypocalcemia. While for many this disorder has little to no effect, for some it can be life-threatening. How could low levels of calcium harm an individual? Low levels of calcium would result in fewer signals sent between the pre- and postsynaptic cell. Low levels of calcium would cause sustained depolarization of the presynaptic cell. Low levels of calcium would not have any effect on synaptic transmission.
Low levels of calcium would result in fewer signals sent between the pre- and postsynaptic cell.
Could an isolated melanin granule move along an actin microfilament? No, motor proteins are specific for the type of filament they bind. Yes, melanin granules have motor proteins. Yes, motor proteins all use ATP to cause a conformation change. None of the other answer options is correct.
No, motor proteins are specific for the type of filament they bind.
Notch and Delta are both transmembrane proteins involved in cell communication in the developing nervous system of vertebrate animals. What makes Notch different from Delta? Notch is a signaling molecule, and Delta is a receptor. All of these choices are correct. Notch is required at higher density than Delta to alter cell fate. Notch is a receptor, and Delta is a signaling molecule.
Notch is a receptor, and Delta is a signaling molecule.
In complex multicellular organisms, bulk flow is an important physiologic character. Why is bulk flow a necessary condition of complex multicellularity? Organisms exhibiting complex multicellularity are large and have cells/tissues that are not in contact with their environment. Systems that can overcome the limits of diffusion must occur for basic physiologic processes to occur. Bulk flow is necessary to move large amounts of liquid through the organism depending on physiologic needs. The tissues can all receive necessary nutrients from the environment, but bulk flow speeds the rate of diffusion. Complex multicellularity is related to the increase in oxygen in the environment. Because bulk flow systems are only related to the delivery of oxygen to tissues, higher environmental oxygen selected for individuals with bulk flow systems. Complex multicellularity reflects cell adhesion between cells, and this cannot happen without bulk flow of signaling molecules from the environment.
Organisms exhibiting complex multicellularity are large and have cells/tissues that are not in contact with their environment. Systems that can overcome the limits of diffusion must occur for basic physiologic processes to occur.
How do mitogen-activated protein (MAP) kinases become inactive? Receptor kinases move apart in the membrane. Ras hydrolyzes GTP to GDP. Phosphatases remove phosphate groups. Ligand diffuses away from the ligand-binding site.
Phosphatases remove phosphate groups.
Which of the following does NOT occur during the follicular phase of the menstrual cycle? Progesterone levels increase to high levels. FSH levels increase. The uterine lining is shed. All of these choices are correct. Ten to twelve oocytes begin to mature.
Progesterone levels increase to high levels. Progesterone levels should decrease
Why are some mutations of Ras associated with cancer? Ras alters ion flow across the cell membrane. Ras is a type of second messenger. Ras activates the MAP kinase signal transduction pathway. Ras binds to growth factor receptors.
Ras activates the MAP kinase signal
Why are some body cells responsive to a particular hormone, whereas others are not? Responsive cells express a receptor specific for the hormone. Whether or not a cell responds to a hormone depends entirely on what type of cell it is (liver cell vs. fat cell vs. nerve cell), because hormones only activate one type of cell. Responsive cells are located closer to the gland that releases the hormone. Responsive cells have complex signal transduction pathways, whereas cells that do not respond to a particular hormone lack these pathways. All of these choices are correct.
Responsive cells express a receptor specific for the hormone.
What effect does the nervous system have on the heart rate? Stimulation by sympathetic nerves causes the pacemaker cells of the AV node to depolarize more rapidly than the pacemaker cells of the SA node. The nervous system does not directly affect the heart rate. Stimulation by parasympathetic nerves causes the heart rate to slow down. Stimulation by either the sympathetic or parasympathetic nerves causes pacemaker cells in the SA node to depolarize more slowly. Stimulation by sympathetic nerves sets the resting heart rate of the pacemaker cells in the SA node.
Stimulation by parasympathetic nerves causes the heart rate to slow down. rest and digest system, conserves energy as it slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles in the gastrointestinal tract.
How is synaptic signaling different from paracrine signaling? Synaptic signaling is longer in duration than paracrine signaling. Synaptic signaling requires receptors to elicit a response in the target cell. All of these choices are correct. Synaptic signaling acts over a longer distance than paracrine signaling. Synaptic signaling specifically involves neurotransmitters that are released from neurons.
Synaptic signaling specifically involves neurotransmitters that are released from neurons. Similar to the paracrine system, but instead located in the synapse
If secretion of adrenocorticotropic hormone (ACTH) is inhibited, then which of the following will result? The thyroid gland would not release thyroid hormone. The adrenal glands would not release cortisol. The anterior pituitary gland would not release TSH. None of the answer options is correct. The posterior pituitary gland would not release ADH.
The adrenal glands would not release cortisol.
If secretion of adrenocorticotropic hormone (ACTH) is inhibited, then which of the following will result? The thyroid gland would not release thyroid hormone. The adrenal glands would not release cortisol. The anterior pituitary gland would not release TSH. None of the answer options is correct. The posterior pituitary gland would not release ADH.
The adrenal glands would not release cortisol. Acth actually causes the glands to release cortisol
What causes the inactivation of a G protein? The alpha subunit catalyzes the hydrolysis of GTP to GDP and inorganic phosphate. The inactive receptor catalyzes the replacement of GTP by GDP. A phosphatase removes the inorganic phosphate group from GTP. The beta and gamma subunits trigger the hydrolysis of GTP to GDP.
The alpha subunit catalyzes the hydrolysis of GTP to GDP and inorganic phosphate.
Which of the following statements about the corpus luteum is FALSE? It is composed of follicle cells that remain in the ovary following ovulation. Progesterone secreted by the corpus luteum maintains the uterine lining. If the egg is not fertilized then the corpus luteum degenerates. None of the other answer options is false. The corpus luteum is maintained first by FSH and then by hCG.
The corpus luteum is maintained first by FSH and then by hCG. Coptpus lutem is a progesterone hormone secreting structure that occurs after the ovum drops an egg. hCG is progesterone secretion FSH helps women release their egg
Imagine that you are examining a mouse that does not produce basal lamina in the skin. How will this mouse be different from a normal, wild-type mouse? The dermis will be disorganized and will lack blood vessels. Cellular junctions will fail to form between the cells of the epidermis. The epidermis and dermis will be strongly connected. The epidermis will not be connected to the dermis. All of these choices are correct.
The epidermis will not be connected to the dermis.
Predict what would happen to a neuron's resting membrane potential if the number of sodium ion channels increased. The membrane potential would become slightly more negative. The membrane potential would remain the same due to the activity of the sodium-potassium pump. The membrane potential would become more positive. The membrane potential would become more negative.
The membrane potential would become more positive.
A botanist working in the Amazon rain forest discovers a new species of orchid. Interestingly, males but not females of a certain wasp species keep visiting the flowers of these orchids. Why? Male wasps are likely attracted by paracrine signals produced by the orchid. Male wasps are likely attracted to the bright colors of the orchids' flowers. Male wasps are likely attracted to the sweet nectar produced by the orchid. The orchid might produce a pheromone similar to that produced by female wasps. Male wasps are likely attracted by growth factors produced by the orchid.
The orchid might produce a pheromone similar to that produced by female wasps.
Which of the following statements about K-strategists is FALSE? They evolve in environments with intense competition for limited food. They produce few offspring. They give birth frequently. They evolve in stable environments. There is a lot of parental investment in the offspring.
They give birth frequently. K-strategists - species that fluctuate near the carrying capacity Since they are almost at breaking point, the birthing rate should decrease instead of increase
A researcher has discovered a new ligand that can pass through the cell membrane and bind to a receptor in the nucleus. Which of the following statements is FALSE regarding this ligand? This ligand is likely a steroid. This ligand is likely nonpolar. This ligand likely binds to a transmembrane receptor. This ligand likely has a similar structure to cholesterol. This ligand likely plays a role in transcription. Score: 1 of 1
This ligand likely binds to a transmembrane receptor.
When a doctor suspects that a patient may have diabetes, she will often have the patient take a glucose challenge test. After the patient drinks a large amount of sugary solution, his blood is drawn and the circulating levels of glucose in the blood are determined. Which of the following curves do you expect from a patient with diabetes? a / b- c\
a / Since diabetes is where insulin is impaired so there is elevated levels of glucose in the blood
What is the end result of activating the MAP kinase pathway? a change in gene expression phosphorylation of multiple cytosolic proteins synthesis of second messenger molecules ion flow
a change in gene expression
The basal lamina is: an area found wherever two different types of tissues meet. a specialized form of the extracellular matrix found beneath all epithelial tissues. a specialized form of the extracellular matrix found only in the skin. an area found beneath all connective tissues that helps them adhere to underlying muscle.
a specialized form of the extracellular matrix found beneath all epithelial tissues.
A new hormone has been isolated from an organism. Although the structure of the hormone has not yet been determined, the hormone is known to exert its effects by forming a hormone-receptor complex that acts as a transcription factor within target cells. What type of hormone is this MOST likely to be? either an amine or a peptide hormone a peptide hormone a steroid hormone either a steroid hormone or an amine hormone either a steroid or a peptide hormone
a steroid hormone
What class of membrane-transport protein is associated with triggering an action potential? a ligand-gated ion channel a pump protein a voltage-gated ion channel a sodium/potassium symporter
a voltage-gated ion channel
The term "saltatory propagation" refers to the: ability of an action potential to "jump" from one node of Ranvier to the next. All of these choices are correct. tendency of an action potential to move in one direction. role of ions such as sodium and potassium in producing the action potential.
ability of an action potential to "jump" from one node of Ranvier to the next.
Tropic hormones: are released from the thyroid gland. suppress the appetite. act on other endocrine organs. regulate the metabolic state of the body. suppress the immune system.
act on other endocrine organs.
A decrease in cell adhesion, by the introduction of an experimental substance to a tissue, compromises the structural integrity of the tissue. Which cell junction would MOST likely be affected by this treatment causing a decrease in the strength of the tissue? hemidesmosomes adherens junctions tight junctions gap junctions
adherens junctions
The two main classes of hormones are: polysaccharide hormones and protein hormones. amine/peptide hormones and steroid hormones. nucleic acid hormones and lipid hormones. lipid-soluble hormones and water-soluble hormones. steroid hormones and lipid hormones.
amine/peptide hormones and steroid hormones.
Animals faced challenges when moving from water to land. What was the single most important adaptation that led to the uncoupling of reproduction and the need for an aquatic habitat? amniotic egg flagellated sperm internal fertilization
amniotic egg MOST IMPORTANT, eggs protect the fetus and you no longer need to lay the egg in water
Body functions such as heart rate, blood flow, and digestion are controlled by the _____ nervous system. voluntary autonomic automatic somatic Score: 1 of 1
autonomic
Why does an action potential travel in one direction down an axon? because it needs to reach the synapse to trigger release of neurotransmitter because voltage-gated sodium channels cannot immediately reopen because voltage-gated potassium channels remain open longer because the diffusion of charge can only occur in one direction
because voltage-gated sodium channels cannot immediately reopen when the axon depolarizes and repolarizes Action potentials are caused when different ions cross the neuron membrane. A stimulus first causes sodium channels to open. Because there are many more sodium ions on the outside, and the inside of the neuron is negative relative to the outside, sodium ions rush into the neuron.
In DNA editing by means of CRISPR, the function of the CRISPR-associated protein 9 (Cas9) is to: (Select all that apply.) bind sgRNA. transcribe CRISPR DNA. cleave target DNA. bind target DNA. translate sgRNA.
bind sgRNA. cleave target DNA. bind target DNA.
Cadherins bind to which type of cytoskeletal element(s)? microfilaments both intermediate filaments and microfilaments microtubules intermediate filaments
both intermediate filaments and microfilaments
The interior of a neuron is more negative than the outside due to the presence of: hydroxyl (OH-) groups. proteins. chloride ions. both proteins and chloride ions.
both proteins and chloride ions.
Inactivation of a cell-surface receptor depends on: the concentration of ligand surrounding the cell. the binding affinity of the receptor. both the binding affinity of the receptor and concentration of ligand surrounding the cell. the activity of phosphatases in the cytosol.
both the binding affinity of the receptor and concentration of ligand surrounding the cell.
Cadherins are: (Select all that apply.) cell adhesion molecules found in cell junctions. proteins involved in attachment of cells to the extracellular matrix. proteins involved in attachment of cells to neighboring cells. proteins that provide a pathway for molecules to move between cells.
cell adhesion molecules found in cell junctions. proteins involved in attachment of cells to neighboring cells.
Which one of the following choices contains structures found in the hindbrain? cerebral cortex cerebellum and pons limbic system thalamus and hypothalamus
cerebellum and pons
Which region is LARGEST in a mammalian brain? hippocampus cerebral cortex cerebellum brainstem
cerebral cortex
Memory and learning take place in which area of the brain? pons and medulla cerebrum and hippocampus hypothalamus cerebellum
cerebrum and hippocampus
A newly developed drug works by blocking thyroid hormone receptors throughout the body. Which of the following would be expected to occur in a patient who is taking this drug? changes in metabolism inability to release cortisol decreased resorption of bone increased uptake of glucose by body cells production of more dilute urine
changes in metabolism
Which of the following is a component of the extracellular matrix produced by an animal cell? cadherin collagen All of these choices are correct. cellulose
collagen
An epithelial tissue is defined as a: few cells embedded into an extensive extracellular matrix. network of cells that use chemical communication. collection of contractile cells. collection of cells that lines cavities or outside surfaces.
collection of cells that lines cavities or outside surfaces.
The extracellular matrix is particularly important for which type of tissue? connective nervous epithelial muscle
connective
A pathologist is carrying out an autopsy. Upon opening the chest cavity, the pathologist sees a thick, fibrous tissue surrounding the heart. This is likely: epithelial tissue. connective tissue. neural tissue. muscle tissue.
connective tissue.
Kisspeptin is a protein in humans that has an important role in initiating secretion of the releasing factor gonadotropin-releasing hormone (GnRH). Endocrinologists are finding that the protein kisspeptin and its receptor are central to sexual maturation at puberty. Neurons that release kisspeptin carry estrogen receptors. If this is a negative feedback system, high levels of estrogen would be expected to: neither increase nor decrease kisspeptin synthesis because steroid hormones do not affect protein synthesis. decrease kisspeptin synthesis. increase kisspeptin synthesis.
decrease kisspeptin synthesis.
The FIRST step following PDGF binding of the receptor is: dimerization. phosphorylation. activation of MAP kinase. activation of gene expression.
dimerization.
Which of the following insect hormones acts on the body tissues to stimulate molting and metamorphosis? brain peptide juvenile hormone All of these choices are correct. PTTH ecdysone
ecdysone
Mammalian steroid hormones are signaling molecules that function in which of the following types of cell signaling? autocrine paracrine endocrine All of these choices are correct.
endocrine
Dynamic instability is a: universal feature of the cytoskeleton. feature of microtubules and microfilaments. feature of microtubules. feature of intermediate filaments. feature of microfilaments.
feature of microtubules.
A researcher is working with mutant mice that demonstrate defects in the formation of connective tissue. These mice likely carry a mutation in a gene encoding what type of growth factor? nerve growth factors (NGFs) histamine neurotransmitters bone morphogenetic proteins (BMPs) fibrinogen growth factors (FGFs)
fibrinogen growth factors (FGFs)
An individual who is experiencing a prolonged period of stress would likely have _____ levels of circulating _____ than an individual who was not experiencing stress. lower; ACTH higher; ADH lower; ADH lower; cortisol higher; cortisol
higher; cortisol
Which portion of the forebrain regulates the endocrine system and body temperature? cerebrum limbic system thalamus hypothalamus
hypothalamus
A newly discovered signaling molecule that binds to a G protein-coupled receptor is being studied by using cells maintained in cell culture. Preliminary results show that the binding of this new ligand causes the activation of adenylyl cyclase. In the next part of this study, a non-hydrolyzable version of GTP (a form of GTP that cannot be converted to GDP) is added to the cell culture dishes and is taken up by the cells. Which of the following would you expect to observe? increased cAMP, increased protein kinase A activity decreased cAMP, decreased protein kinase A activity increased cAMP, decreased protein kinase A activity decreased cAMP, increased protein kinase A activity
increased cAMP, increased protein kinase A activity
Structures known as microvilli are associated with: adhesion to the extracellular matrix. communication between cells. increased surface area for nutrient absorption. increased surface area for gas exchange.
increased surface area for nutrient absorption.
Which of the following is an example of the effector's role in maintaining homeostasis? vasodilation on a cold winter day decrease in body temperature on a cold day increased sweating on a hot summer day increased body temperature during a workout
increased sweating on a hot summer day
In many cells, the adhesion to the extracellular matrix through integrins causes the activation of kinases in the cytoplasm. This suggests that: extracellular matrix proteins are receptors and integrins are ligands. integrins promote the activation of signal-transduction pathways. integrins are kinases.
integrins promote the activation
In skin, the cells of the epidermis connect to the basal lamina through cellular junctions known as hemidesmosomes. Select the cytoskeletal element that helps maintain the integrity of this connection. intermediate filaments both intermediate filaments and microfilaments microfilaments microtubules
intermediate filaments
Which of the following sets of terms belong together? voluntary, autonomic, parasympathetic involuntary, somatic, parasympathetic involuntary, autonomic, sympathetic voluntary, somatic, sympathetic
involuntary, autonomic, sympathetic
he basal lamina: All of these choices are correct. is a specialized extracellular matrix found beneath epithelial tissues. is found on top of the epidermis of the skin. links to epithelial cells through tight junctions. is a cell-rich layer.
is a specialized extracellular matrix found beneath epithelial tissues.
Which type of protein adds a phosphate group to another molecule? G protein kinase phosphatase phosphorylase
kinase
Which of the following brain regions controls drives, instincts, and emotion? cerebellum thalamus limbic system cerebrum
limbic system It controls the basic emotions (fear, pleasure, anger) and drives (hunger, sex, dominance, care of offspring).
A stroke occurs when blood flow to a region of the brain is interrupted, damaging the cells in that region. What symptoms might you see if a person suffered a stroke in their cerebellum? difficulty speaking loss of sensory perception loss of balance and coordination visual impairment
loss of balance and coordination
Cas9 cleaves both strands of the target DNA. Which of the following could occur when cells will try to repair the damage after cleavage by Cas9? (Select all that apply.) loss-of-function mutations within the targeted gene mutations that result in changes to the open reading frame (ORF) of the targeted gene deletions of the targeted gene the insertion of a DNA sequence into the targeted gene no change in the targeted gene
loss-of-function mutations within the targeted gene mutations that result in changes to the open reading frame (ORF) of the targeted gene deletions of the targeted gene the insertion of a DNA sequence into the targeted gene no change in the targeted gene
Ovulation is triggered by a surge of which of the following hormones? follicle stimulating hormone luteinizing hormone testosterone estrogen progesterone
luteinizing hormone rise of LH ("LH surge") triggers ovulation and development of the corpus luteum.
Imagine you created a toxin such that when a neuron fired an action potential, the toxin would bind immediately to the sodium-potassium pump at the top of the action potential, but the sodium and potassium channels would still function. What process(es) would be affected? the depolarization phase of an action potential maintaining resting potential and returning to resting potential after the hyperpolarization phase of an action potential the hyperpolarization phase of an action potential maintaining resting potential returning to resting potential after the hyperpolarization phase of an action potential
maintaining resting potential and returning to resting potential after the hyperpolarization phase of an action potential
The property of dynamic instability implies that the individual protein subunits of microtubules are held together by: noncovalent interactions. covalent bonds. disulfide bonds. All of these choices are correct.
noncovalent interactions.
Growth factors, such as platelet-derived growth factor, function in _____ signaling. endocrine autocrine paracrine contact-dependent
paracrine
The signal to "rest and digest" comes from the _____ system. sympathetic somatic parasympathetic peripheral
parasympathetic
Which type of cell-surface receptor undergoes changes in phosphorylation in response to binding of its ligand? both the G protein-coupled receptor and the receptor kinase G protein-coupled receptor ligand-gated ion channel receptor kinase
receptor kinase
A researcher is using a small molecule as an inhibitor to manipulate a signaling pathway. This inhibitor prevents phosphorylation and MOST likely targets a: G protein. G protein-coupled receptor. receptor kinase. ligand-gated ion channel. phosphatase.
receptor kinase.
Inhibition of the flexor muscle during the knee-extension reflex is an example of: negative feedback. All of these choices are correct. homeostasis. reciprocal inhibition.
reciprocal inhibition.
Which of the following is the CORRECT path taken by sperm from site of production to site of ejection? epididymis, seminiferous tubules, vas deferens, urethra, ejaculatory duct vas deferens, epididymis, seminiferous tubules, ejaculatory duct, urethra seminiferous tubules, vas deferens, ejaculatory duct, epididymis, urethra seminiferous tubules, epididymis, vas deferens, ejaculatory duct, urethra epididymis, seminiferous tubules, vas deferens, ejaculatory duct, urethra
seminiferous tubules, epididymis, vas deferens, ejaculatory duct, urethra
In maintaining homeostasis of body temperature, what role does the hypothalamus play? effector sensor stimulus response
sensor
Resting potential is generated mainly by the outward movement of K+ ions from inside the cell. 2. The voltage changes shown in the figure are measured just across the plasma membrane 3. The changes in voltage seen at #2 and #4 in the figure are caused by similar movements, in the same direction, of the same types of ions across the membranes. 4. The trace in the figure is following the voltage change as it moves down the axon. 5. The voltage change shown in the figure is an all-or-nothing response. 6. Different ion channels are responsible for generating the voltage change seen at #2 and #4 in the figure. 7. All voltage changes along the plasma membrane of an axon have the characteristic shape shown above. 8. The changes in voltage shown in the figure are due to ligand-gated ion channels opening and closing along the axon. 9. An EPSP of sufficient strength to reach threshold occurred at #1 on the figure. 10. A membrane that has no K+ channels will have a resting membrane potential that is higher than the one shown on the figure.
t t f f t t t f t t
Which brain region is associated with language in humans? temporal lobe frontal lobe parietal lobe occipital lobe
temporal lobe
4.An interneuron may receive multiple stimuli from the same sensory neuron over a very short period of time. The firing rate of the receiving neuron is proportional to the number of signals received from the sensory neuron over time. Of which of the following is this an example? spatial summation hyperpolarization action potential temporal summation
temporal summation
In response to LH and FSH, testes secrete: sperm. estrogen. TDF. ejaculate. testosterone.
testosterone. LH and FSH are steroid hormones that secrete both testosterone and estrogen
The MOST likely reason(s) a metastatic tumor cell might lose its connection to the basal lamina would be: the loss of integrin proteins from the cell's surface, or a change in the type of integrin proteins present on the cell's surface. a change in the composition of the basal lamina. a change in the type of integrin proteins present on the cell's surface. the loss of integrin proteins from the cell's surface.
the loss of integrin proteins from the cell's surface, or a change in the type of integrin proteins present on the cell's surface.
The gray matter on the outside of the brain appears gray because: the neurons are not myelinated. all dendrites in the brain are located there. the neuronal cell bodies are located here. the neurons are protected by something other than myelin that makes it appear gray.
the neuronal cell bodies are located here.
The cellular changes associated with long-term potentiation are localized to: the postsynaptic cell. the presynaptic cell. both pre- and postsynaptic cells.
the postsynaptic cell.
In the G protein-coupled signal transduction pathway, phosphatases are responsible for the inactivation of: adenylyl cyclase. protein kinase A. All of these choices are correct. the alpha subunit of a G protein. the protein target activated by protein kinase A. Score: 1 of 1
the protein target activated by protein kinase
.Dilated pupils, inhibited digestive activity, increased respiratory rate, and release of glucose from the liver are all signs of activity of: both divisions of the autonomic nervous system. the sympathetic division of the autonomic system. the somatic nervous system. the parasympathetic division of the autonomic system.
the sympathetic division of the autonomic system. nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response.
How does an "activated" receptor transfer information into the cell? through a conformational change of the receptor by increased translation of the receptor by decreased phosphorylation of the receptor by altering the ligand-binding site of the receptor
through a conformational change of the receptor
ich of the following cell junctions is involved in creating a barrier between cells? adherens junction tight junction desmosome
tight junction
What is the function of adenylyl cyclase? to phosphorylate cyclic AMP to form protein kinase A to phosphorylate protein kinase A to form cyclic AMP
to form cyclic AMP
The strength of collagen comes from its: triple helical structure and bundling. ability to bind to polysaccharide molecules. triple helical structure and bundling, as well as its amino acid sequence. amino acid sequence.
triple helical structure and bundling.
