Sensory Physiology
- Multiple Choice
| Key/
Page
|
No. | |
| b
208 | 1. | The process of transduction associated with membrane receptors is inextricably linked to
a. a stimulus interacting with peripheral membrane proteins.
b. ion channels present in the membrane.
c. the establishment of a transmembrane potential.
d. ions moving up their concentration gradient.
e. none of these.
|
| a
208 | 2. | It is believed that the group of channels responsible for sensing osmotic stress evolved first. This group of channels are
a. mechanically gated.
b. ion gated.
c. voltage-gated.
d. ligand-gated.
e. receptor-activated.
|
| d
208,
211 | 3. | A receptor cell
a. is involved in converting stimulus energy into action potentials.
b. is specialized to respond to a particular sensory modality.
c. can often be found in a sense organ grouped with other cells responsive to the same adequate stimulus.
d. all of these.
e. none of these.
|
| b
214 | 4. | Which receptor for vibrations and pressure is found in birds?
a. Pacinian corpuscle
b. Herbst corpuscle
c. Avian corpuscle
d. tactile disc
e. none of these.
|
| b
208,
209 | 5. | One can categorize sensory receptors according to sensory modality. Which of the following is NOT a type of receptor?
a. photoreceptor
b. intelreceptor
c. mechanoreceptor
d. chemoreceptor
e. thermoreceptor
|
| e
213 | 6. | Stimulus intensity is typically encoded in
a. action potential amplitude.
b. frequency of action potentials.
c. number of receptors activated.
d. Both action potential and amplitude and frequency.
e. Both action potential frequency and number of receptors stimulated.
|
| a
213 | 7. | Sensory adaptation refers to
a. the ability of receptors to become less responsive to a stimulus of a given intensity.
b. a phenomenon through which a receptor specialized for one sensory modality evolves to respond to another sensory modality.
c. the ability of receptors to become more sensitive to a stimulus as a consequence of repeated exposure.
d. none of these.
|
| e
213 | 8. | A tonic receptor
a. quickly adapts to a stimulus.
b. has an off response.
c. ignores continuous information.
d. all of these.
e. none of these.
|
| d
239 | 9. | Which of the following statements about light detection is TRUE?
a. Light detection is synonymous with vision.
b. Light detection is always initiated in a rod or cone photoreceptor, though these need not be located in an eye.
c. Even in its most primitive form, light detection evolved in structures dedicated to this purpose.
d. Light detection evolved numerous times in a variety of structures.
e. None of these.
|
| d
239 | 10. | Which of the following statements about eyespots is NOT true?
a. Eyespots contain photoreceptor cells.
b. Eyespots are found in planarians and cnidarians.
c. Eyespots contain pigments that assure only light coming from a particular direction is absorbed.
d. Eyespots form an image perceived by the animal’s ganglion.
e. Eyespots have a large visual field to which they respond.
|
| a
240 | 11. | The tough, outer layer of connective tissue that covers most of the eyeball is the
a. sclera.
b. eyelid.
c. eye socket.
d. choroid.
e. cornea.
|
| c
239 | 12. | Which of the following statements is NOT true?
a. The Amoeba is capable of responding to light.
b. The surface of rhabdomeric photoreceptors consists of parallel microvilli.
c. Due to the size of their visual field, pinhole eyes do not form images.
d. Recognition of predator-prey movement requires a visual system that permits the formation of an image.
e. Butterflies sense light with their genitalia.
|
| b
242 | 13. | Pupillary constriction results from contraction of the ________ muscle of the iris as a consequence of ________ stimulation.
a. circular; sympathetic
b. circular ; parasympathetic
c. radial; sympathetic
d. radial; parasympathetic
e. suspensory; somatic motor
|
| d
243 | 14. | Which of the following strategies do animals use to help protect the retina from damage due to ultraviolet radiation?
a. pigmented cornea
b. pigmented lens
c. pigmented oil droplets in the photoreceptor inner segments
d. all of these.
e. none of these.
|
| c
244 | 15. | In mammals, contraction of the ciliary muscle of the eye leads to
a. decreased pupil size.
b. increased pupil size.
c. increased curvature of the lens.
d. decreased curvature of the lens.
e. squinting.
|
| e
244 | 16. | Accommodation
a. is the processes focusing the visual image on the retina.
b. occurs in fish by moving the lens either forward or backward.
c. can be accomplished by changing the fluid volume in the optic chamber .
d. only two of these.
e. all three of these.
|
| c
245,
246 | 17. | Which of the following does NOT form one of the neural layers of the retina?
a. rod and cone photoreceptors
b. bipolar cells
c. retinal pigment epithelium
d. ganglion cells
e. All of these are components of the neural retina.
|
| b
245 | 18. | The ____________ is the region of the retina where the optic nerve exits and the blood vessels enter the eye.
a. fovea
b. optic disc
c. macula lutea
d. corpus luteum
e. pupil
|
| a
247 | 19. | The part of a visual photoreceptor in which the detection of light (signal transduction) is initiated is the
a. outer segment.
b. inner segment.
c. synaptic terminal.
d. nucleus.
e. Golgi stacks.
|
| a
248 | 20. | The cyclic nucleotide whose modulation is most closely associated with phototransduction in vertebrates is
a. cGMP.
b. cCMP.
c. cAMP.
d. cTMP.
e. 5′-GMP.
|
| e
248 | 21. | Transducin
a. activates adenylyl cyclase resulting in the formation of cAMP.
b. activated calcium-activated channels leading to depolarization of the receptor cell.
c. activates the messenger pathway leading to an increase in cGMP.
d. is found in the inner segment of photoreceptor cells.
e. is a G-protein.
|
| a
248 | 22. | In terms of vision, the first order cells are the _____, while the _____ and _____ are the second and third order cells, respectively.
a. photoreceptors; bipolar cells; ganglion cells
b. photoreceptors; ganglion cells; bipolar cells
c. bipolar cells; ganglion cells; photoreceptors
d. bipolar cells; photoreceptors; ganglion cells
e. ganglion cells; bipolar cells; photoreceptors
|
| b
250 | 23. | Which of the following features account(s) for the greater acuity that occurs in cones, relative to the rods?
a. Different cone opsins have different absorbance maxima for wavelengths of light.
b. There is little convergence in the cone system.
c. Cones are less sensitive (require a stronger stimulus) than rods.
d. All of these contribute to acuity.
e. None of these influence acuity.
|
| a
250 | 24. | The term light adaptation refers to
a. the changes that occur in the visual pigment system when going from a dark into a light environment.
b. the evolutionary changes that enable a species to maintain a diurnal life style.
c. the changes that occur in visual pigment system when going from a light into a dark environment.
d. none of these.
|
| e
250, 251 | 25. | Which of the following pairs are NOT related in any way?
a. night blindness and retinene
b. dark adaptation and sunlight
c. long (L) cones and the color yellow
d. primates and trichromatic vision
e. cones and high visual sensitivity
|
| a
253 | 26. | On-center ganglion cells _____________ their spike frequency when the center of their receptive field is stimulated by light.
a. increase
b. decrease
c. do not change
|
| a
253 | 27. | Information from the medial retina of each eye crosses to the opposite side to join its corresponding lateral visual field at the level of the
a. optic chiasma.
b. optic nerve.
c. optic tract.
d. corpus callosum.
e. geniculate nucleus.
|
| b
253 | 28. | The term optic radiations refers to
a. visual tracts that cross between the cerebral hemispheres.
b. fiber tracts carrying information in the visual pathways from the lateral geniculate nucleus of the thalamus to different zones in the cortex.
c. the evolution of diverse specialized organs for vision.
d. the radial muscles in the iris that enable dilation of the pupil.
e. the visual field associated with off-center ganglion cells.
|
| b
247 | 29. | In which portion of the photoreceptor is the light detecting pigment found?
a. inner segment
b. outer segment
c. middle segment
d. synaptic segment
e. transducing segment
|
| d
258 | 30. | Phototransduction in invertebrates differs from that in vertebrates in that in invertebrates
a. no G-proteins are involved.
b. no cation channels are involved.
c. no opsins are involved.
d. photoreceptors depolarize in response to stimulation.
e. first-order cells hyperpolarize in response to stimulation.
|
| b
218 | 31. | Statocysts are sensory organs used to perceive
a. consciousness, or state of being.
b. an organism’s orientation in space.
c. surface hardness.
d. none of the above.
|
| e
235
| 32. | Which of the following pairs is NOT related?
a. Sour taste and blocking of K+ channels
b. Salty taste and ENaC channels
c. Umami taste and amino acids
d. Sweet taste and IP3 induced release of calcium
e. none of these.
|
| c
222 | 33. | The otolith organs are
a. the ampulla and the ventricle.
b. the uvula and the spicule.
c. the utricle and the saccule.
d. cupula and ampulla.
|
| a
221, 222 | 34. | In the mammalian vestibular apparatus, the ________ are used to detect ________ while the ________ are used to detect ________.
a. semicircular canals; angular acceleration; otolith organs; linear acceleration
b. semicircular canals; linear acceleration; otolith organs; angular acceleration
c. hair cells; linear acceleration; scale cells; angular acceleration
d. hair cells; angular acceleration; scale cells; linear acceleration
|
| d
226, 239 | 35. | The pitch of a sound is determined by the ________ of vibrations, and in that respect is most similar to the ________ of light.
a. amplitude; brightness
b. amplitude; wavelength
c. frequency; brightness
d. frequency; wavelength
|
| d
233,
234 | 36. | Which of the following statements is NOT true?
a. Taste and smell senses are highly variable in sensitivities among species.
b. The intraspecies roles of olfaction are largely mediated by pheromones.
c. Sensilla are specialized projections from the cuticle of insects and are involved in chemical sensing
d. In humans, the cortical gustatory area is located in the temporal lobe.
e. The modality for mammalian taste receptors is called a tastant.
|
| e
228 | 37. | In the normal hearing pathway, sound waves have to pass from air to liquid as sound is transmitted from the external ear to the inner ear. This occurs as a result of
a. the increase in pressure on the oval window relative to the pressure on the tympanic membrane.
b. the increase in force applied to the oval window which is accomplished by the lever action of the inner ear ossicles.
c. the difference in surface areas of the tympanic membrane and the membrane of the oval window .
d. two of these.
e. all of these.
|
| b
229 | 38. | The cochlea of each ear contains about 16,000 hair cells. Even though they are in the minority, it is the ____________ hair cells that are principally responsible for transducing sound waves into what we perceive as sound sensations.
a. outer
b. inner
c. utricular
d. saccular
e. ampullar
|
| c
230, 231 | 39. | Due in part to the physical properties of the basilar membrane, the cochlea is tuned so that
a. high amplitude sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
b. low amplitude sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
c. high frequency sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
d. low frequency sounds are perceived optimally at the base of the narrow end of the cochlea (toward the oval window).
|
| c
232 | 40. | The pitch of a sound is perceived in part due to frequency matching in the action potentials of the ________, and in part due to spatial (tonotopic) mapping of the ________.
a. hair cells; basilar membrane
b. hair cells; vestibular membrane
c. auditory neurons; basilar membrane
d. auditory neurons; vestibular membrane
e. auditory neurons; tympanic membrane
|
- True and false
False 1. Ion currents can be found in all vertebrates (eukaryotes) but not in prokaryotes.
208
True 2. The detection of physical forces in the environment is most likely the most ancient of the 208, senses.
217
True 3. Evolutionary adaptations related to movement have had a significant impact on the size 221 of the semicircular canals.
True 4. Animal communication in oceans occurs best at low frequencies because salts in seawater
228 absorb high-frequency sounds.
False 5. Most deep-sea dwelling organisms have evolved L (red) cones as a way to compensate
251 for the diminished penetration of blue wavelength light into the deep sea.
True 6. Polarized light is used by some butterflies to find a mate.
252
False 7. Light induced phototransduction in both compound eyes and vertebrate eyes involves
258 depolarization of the photoreceptors cells, rods and cones.
True 8. Mammals have a cold-gated channel that is structurally similar to the heat-gated channel
259 used by pit vipers to locate their prey.
False 9. Passive electroreception uses an electric organ located in the tail of certain fish.
261
False 10. The vertebrate eye has a blind spot because it is formed through a series of invaginations
256 of the epidermis.
- Matching (correct answers are aligned with each number; e.g., #1 matches with letter a)
| 1. | Generator potential | a. | Afferent neuron |
| 2. | Mechanoreceptor | b. | Touch |
| 3. | Chemoreceptor | c. | Taste |
| 4. | Thermally gated channels | d. | Paramecium |
| 5. | Electroreceptors | e. | Electric fields |
| 6. | Magnetoreceptor | f. | Magnetic fields |
| 7. | Tonic | g. | Slowly adapting |
| 8. | Sensory cell | h. | Adequate stimulus |
| 9. | Acuity | i. | Receptor density |
| 10. | Ommatidia | j. | Compound eye |
- Essay
Page No.
256 1. Compare and contrast the development of the retina in cephalopods and humans.
251,252 2. Considering how animals adapt through evolution to live in their environment, explain why whales lack blue cones. Would you expect this to reflect the condition of its common ancestor with terrestrial mammals, or would you consider this a derived trait?
215,216 3. Describe and discuss how lateral inhibition would be involved in the localization of pain to an ingrown toenail on lateral side of your left big toe.
235 4. Develop an argument that supports the following statement. Salt receptors provided an adaptive advantage to early humans?
260 5. Experiencing pain through the fast pain pathway has the obvious benefit of eliciting a withdrawal reflex to prevent further damage from the painful stimulus. What benefit do you think might be derived from experiencing persistent dull pain through the slow pain pathway?
Endocrine Systems
- Multiple Choice
Key/
Page |
No.
| |
| c
272 | 1. | A tropic hormone is one whose function is to
a. stimulate the central nervous system.
b. trigger cellular development.
c. stimulate endocrine tissue to secrete hormones.
d. stimulate growth and development.
|
| e
273 | 2. | Which of the following statements about the endocrine system is true?
a. Each endocrine gland secretes a single type of hormone.
b. Each endocrine hormone is secreted by a single endocrine tissue.
c. Each endocrine hormone acts on a single target tissue.
d. Each endocrine hormone activates a single type of receptor.
e. Many endocrine tissues have other non-endocrine functions.
|
| e
271 | 3. | Steroid hormones
a. are lipophilic.
b. may be converted into other hormones.
c. are derived from cholesterol.
d. are synthesized in steroidogenic cells and organs.
e. all of these.
|
| b
271 | 4. | Steroid hormones differ from peptide hormones in that
a. the site of synthesis of steroids is distinct from their site of release.
b. the former are not stored, but instead are released upon synthesis.
c. the former are synthesized ubiquitously.
d. they don’t have a specific receptor protein with which they interact.
e. none of these.
|
| e
275 | 5. | Endocrine disrupting compounds
a. may often mimic the effects of estrogen.
b. are human made substances
c. can be passed from one generation to the next.
d. only two of these.
e. all of these.. |
| e
324 | 6. | Intracellular calcium levels have an effect on
a. cell motility.
b. cilia action.
c. secretion by exocytosis.
d. muscle contraction.
e. all of these.
|
| a
277 | 7. | Down-regulation
a. refers to the expression of fewer receptors at the cell surface as part of a negative-feedback mechanism.
b. refers to the decrease in cortisol secretion that occurs as an animal’s metabolism slows down to its basal level.
c. occurs in response to too little hormone reaching the target cells.
d. is an idiopathic response to endocrine disrupters.
e. occurs in response to the excretion of excess hormone by the kidneys.
|
| a
278 | 8. | In the context of endocrine regulation, permissiveness refers to
a. one hormone enhancing the responsiveness of a target cell to another hormone.
b. the combined action of several hormones acting complementary to one another.
c. the expression of receptors by a cell allowing it to respond to a hormone.
d. the increase in receptor number that occurs on the surface of a target cell during hyposecretionof a hormone .
e. none of these.
|
| e
324 | 9. | Which of the following is NOT true?
a. Calcium can be stored in the body and sodium cannot.
b. Parathyroid hormone is the primary hormone responsible for maintaining calcium homeostasis.
c. Calcitonin is not essential for routine maintenance of calcium concentration in mammals.
d. Calcium is required for normal blood clotting.
e. All of these are true statements.
|
| a
282 | 10. | The pineal gland secretes the hormone
a. melatonin.
b. melanin.
c. melanocyte stimulating hormone.
d. estradiol.
e. melanopsin.
|
| e
285 | 11. | Which of the following is NOT a normal function of melanocyte stimulating hormone (MSH)?
a. camouflage
b. immune suppression
c. pelage of feathers
d. appetite control
e. All of these are normal functions.
|
| c
286 | 12. | Vasopressin, or antidiuretic hormone, is secreted from the posterior pituitary in response to input from hypothalamic osmoreceptors which were activated by
a. increased levels of osmium in the blood.
b. softening of the cervical os (the outlet of the uterus).
c. increased plasma osmolarity.
d. increased blood volume.
e. increased blood pressure.
|
| b
286 | 13. | In lower vertebrates, arginine vasotocin (AVT) is involved in regulating several different processes. Which of the following AVT-stimulated events does NOT involve smooth muscle contraction?
a. vasoconstriction
b. ejection of milk from mammary glands.
c. oviposition
d. birth in viviparous snakes.
e. All of these involve smooth muscle contraction.
|
| a
288 | 14. | The anterior pituitary hormone ____________ stimulates the mammary glands to produce milk.
a. prolactin
b. oxytocin
c. luteinizing hormone
d. growth hormone
e. none of these.
|
| d
289 | 15. | Which of the following have capillaries which are part of a portal system?
a. liver
b. pituitary
c. hypothalamus
d. liver, pituitary, and hypothalamus
e. pituitary and hypothalamus
|
| d
290 | 16. | Cortisol is secreted by the adrenal cortex in response to stress. In addition to its function in a stress response, it functions in negative feedback by
a. inhibiting the hypothalamus so that corticotropin releasing hormone (CRH) secretion is reduced.
b. reduces the secretion of ACTH by the anterior pituitary.
c. suppressing its own secretion by its actions on the hypothalamus and anterior pituitary.
d. all of these.
d. none of these.
|
| b
292 | 17. | Metabolic effects of growth hormone include
a. stimulating cell division.
b. elevating blood glucose levels.
c. elevating glycogen breakdown by muscles.
d. promoting glucose uptake by muscles.
e. all of these except promoting glucose uptake by muscles.
|
| d
292 | 18. | IGF-I and IGF-II are examples of
a. somatomedins.
b. peptide hormones.
c. endocrine hormones.
d. all of these.
e. none of these.
|
| a
327 | 19. | Absorption of calcium and phosphate by the intestine is regulated by
a. parathyroid hormone.
b. thyroid hormone.
c. calcitonin.
d. phosphate concentration in the blood.
e. Vitamin C levels in the blood.
|
| d
299 | 20. | Unlike steroid hormones, thyroid hormones (T3 and T4) can be stored after synthesis. This is due to the fact that
a. thyroid hormones are not membrane-permeant molecules.
b. thyroid hormones are protein hormones, and are stored in vesicles until an elevation in intracellular calcium stimulates their release.
c. thyroid hormones are sequestered in colloid, surrounded by a wall of follicular cells, and that presents too much of a barrier for the hormones to pass through.
d. thyroid hormones remain attached to a larger protein molecule until the thyroid is stimulated to secrete them, at which point they are cleaved from the protein and diffuse from the cell into the circulation.
e. None of the above is correct.
|
| c
270 | 21. | Which of the following has NO relationship?
a. peptide hormones and secretory granules
b. steroids and lipid droplets
c. Catecholamines and adrenal cortex
d. peptide hormones and rough endoplasmic reticulum
e. thyroid hormones and lipophilic molecules
|
| e
301 | 22. | Which of the following are effects of thyroid hormone?
a. increased basal metabolic rate
b. increased conversion of glycogen to glucose
c. increased conversion of glucose to glycogen
d. increased expression of catecholamine target-cell receptors
e. all of these.
|
| b
303 | 23. | Regulation of thyroid hormone synthesis is primarily under the control of
a. thyroid hormone.
b. thyroid stimulating hormone.
c. thyroid releasing hormone.
d. thyrotropin stimulating hormone.
e. thyrotropin releasing hormone.
|
| d
304 | 24. | Hypothyroidism can result from
a. a deficiency in thyrotropin releasing hormone.
b. a deficiency in thyroid stimulating hormone.
c. insufficient amounts of iodine in the diet.
d. all of these.
|
| e
304 | 25. | Symptoms of hyperthryoidism include
a. inability to tolerate heat.
b. excessive perspiration.
c. anxiety.
d. weakness.
e. all of these.
|
| a
304 | 26. | Mineralocorticoids such as aldosterone are produced primarily in the ____ of the adrenal gland.
a. zona glomerulosa
b. zona fasciculata
c. zona reticularis
d. adrenal medulla
e. chromaffin cells
|
| e
276 | 27. | Endocrine rhythm, the rise and fall in hormone level,
a. is a response to external clues.
b. occurs in diurnal animals.
c. is influence by endogenous oscillators.
d. two of these.
e. all of these.
|
| b
306 | 28. | The main role of glucocorticoids is to
a. enhance sodium reuptake from the urine.
b. elevate glucose levels in the blood.
c. enhance the elimination of sugars in the urine.
d. enhance the reuptake of sugar from tubular fluids in the kidney.
e. none of these.
|
| c
306 | 29. | Prolonged elevation of glucocorticoids due to stress is associated with ________, which illustrates the folly of cramming for exams, especially during all-nighters!
a. increased growth of facial hair
b. increased water retention.
c. memory loss
d. fatigue
e. none of these.
|
| d
307 | 30. | In female mammals, the androgen produced by the adrenal cortex that is of physiological significance in females is
a. testosterone (TST).
b. dihydroxytestosterone (DHT).
c. estrogen (EST).
d. dehydroepiandrosterone (DHEA).
e. thalidomide.
|
| a
308 | 31. | The adrenal medulla consists of modified, post-ganglionic sympathetic neurons called chromaffin cells which store norepinephrine and epinephrine in chromaffin granules. In this situation, when these chemical transmitters are released they act as
a. neurohormones.
b. neurotransmitters.
c. stress inducers.
d. glucocorticoids.
e. mineralocorticoids.
|
| a
309,
310 | 32. | Epinephrine and norepinephrine
a. have a generalized vasoconstrictor effect.
b. promote vasodilation of blood vessels supply muscles.
c. promote mobilization of stored carbohydrates.
d. dilate respiratory airways.
e. none of these.
|
| c
310 | 33. | In many respects, cortisol and epinephrine duplicate each other’s effects in the stress response. However, cortisol and NOT epinephrine
a. causes an elevation in glucose in the blood.
b. causes an increase in fatty acids in the blood.
c. causes an increase in amino acids in the blood.
d. causes a decrease in glucose in the blood.
e. causes a mobilization of carbohydrates.
|
| a
279 | 34. | Y-organs in the head of decapods
a. produce crustecydsone
b. produce chromatophorotropins for changing cuticle color.
c. hyperglycemic hormone to regulate glucose levels.
d. all of these.
e. none of these.
|
| D
314 | 35. | _____ are one of a few cell types that store glucose in the form of glycogen.
a. Glial cells
b. Liver cells
c. Muscle cells
d. All of these.
e. None of these.
|
| A
316 | 36. | Which of the following is NOT a function of the liver as regards glucose homeostasis?
a. secreting ketone bodies in response to excess plasma glucose levels
b. storing glycogen when excess glucose is available
c. releasing glucose when plasma glucose levels drop
d. converting organic chemicals like amino acids into glucose via gluconeogenesis
e. All of these are functions of the liver relating to glucose homeostasis.
|
| D
315 | 37. | Glucose sparing refers to a phenomenon occurring during the
a. absorptive phase of metabolism in which recently ingested glucose is saved in the form of glycogen for future use.
b. postabsorptive phase of metabolism in which glucose ingested earlier is saved in the form of glycogen for use during prolonged fasting.
c. postabsorptive phase of metabolism in which numerous body tissues release glucose for immediate use by the brain.
d. postabsorptive phase of metabolism in which numerous body tissues switch to metabolizing alternative, non-glucose energy sources, so that glucose remains available for the brain.
|
| B
317 | 38. | Somatostatin functions in glucose homeostasis by
a. promoting reduced growth of the body, decreasing the need of individual cells for glucose, and thereby promoting glucose sparing.
b. inhibiting digestion and absorption of nutrients, preventing hyperglycemia.
c. inhibiting secretion of prolactin, reducing production of lactose for milk, and preventing hypoglycemia.
d. doing all of these.
e. doing none of these.
|
| C
318 | 39. | In most cells, insulin stimulates uptake of glucose by
a. penetrating the cellular membranes itself, and thereby providing a pathway for glucose to enter the cells.
b. activating insulin receptors, which are themselves glucose transporters.
c. stimulating the recruitment of glucose transporters to the membrane, which in turn facilitate the import of glucose.
d. activating the transcription and translation of glucose transporter-genes, increasing their expression.
e. altering the ratio of intracellular sodium concentrations to extracellular sodium concentrations in a way that favors co-transport of glucose and sodium.
|
| c
320 | 40. | Glucagon secretion occurs in response to
a. parasympathetic stimulation.
b. sympathetic stimulation.
c. low levels of plasma glucose.
d. low levels of plasma amino acids.
e. all of these. |
- True and Flase
True 1. Insulin is the only hormone capable of lowering blood glucose levels.
318
False 2. Calcitonin is produced by the C cells of the parathyroid gland.
327
True 3. If the demand for calcium needed to produce egg shells regularly exceeds the
332 level of calcium intake, egg-laying birds may replace all of their medullary bone to meet that demand.
True 4. Steroids are neutral lipids.
269
False 5 Steroid hormones differ from peptide hormones in that all steroid hormones are
275 known to bind nuclear receptors.
True 6. Annetocin is an annelid hormone that is similar to vertebrate oxytocin.
279
False 7. The pineal gland connects to the hyothalamus via a portal system.
283
True 8. All eukaryotes have clock genes which interact in a cyclic fashion that lasts about
283 24 hours.
False 9. Melanopsin is a gene involved in skin pigmentation.
284
True 10. Lactotrophs secrete prolactin.
288
- Matching (correct answers are aligned with each number; e.g., #1 matches with letter a)
| 1. | Pineal gland | a. | Melatonin |
| 2. | Hypothalamus | b. | Multifaceted stress response |
| 3. | Anterior pituitary | c. | Adrenocorticotropic hormone |
| 4. | Posterior pituitary | d. | Oxytocin |
| 5. | Parathyroid | e. | Vitamin D activation |
| 6. | Thyroid | f. | Calcitonin |
| 7. | Adrenal cortex | g. | Cortisol |
| 8. | Adrenal medulla | h. | Catecholamines |
| 9. | Pancreatic α-cells | i. | Glucagon |
| 10. | Pancreatic β-cells | j. | Insulin |
- Essay
Page No.
314 1. A healthy person has about two month’s worth of energy stored in fat. Oxidation of fats yields about 9 kcal/gram. Assuming a healthy adult requires 1500 kcal/day to function, how many grams of fat does a typical, healthy adult have? How much glycogen would a person have to store to have a comparable energy supply, assuming a caloric yield of 4 kcal/gram?
* 2. In systems geared toward maintaining homeostasis, there is generally some parameter that is monitored by a sensor which responds to deviations from a set point by stimulating a response from an effector system that in turn causes an adjustment to the parameter. Give an example from the endocrine system of homeostatic control. Be sure to identify the sensor(s), parameter(s) and effector(s) and how they interact to maintain homeostasis. If negative feedback is involved, describe that aspect as well.
* The answer to this question could be drawn from multiple points in the chapter.
321-323 3. Distinguish between diabetes mellitus type I and type II. Which is more pharmacologically tractable? Why?
330 4. Compare and contrast the interactions between parathyroid hormone and vitamin D in controlling plasma calcium levels. Be sure to include the directional change in calcium levels, the organs involved, and where the hormone and vitamin D are having their effects.
331 5. Discuss the homeostatic control of plasma phosphate levels in situations where phosphate levels are too high and where they are too low. Be sure to include such things as the hormones involved, organs involved, and the direction of change in phosphate levels
