Hypothalamus-Pituitary: Structure & Function

The correct answer is vasopressin. ADH is vasopressin's other name, causing the kidney to retain more water in the blood, thereby affecting water balance. Other hormones listed are either not made in the hypothalamus (GH, Testosterone, and PTH) or affect growth hormone secretion, not water balance directly (GHIH, a.k.a. somatostatin).

Question 34 1 / 1 pts Which of the following hormones is produced in the hypothalamus and has a direct effect on body water balance? Vasopressin Parathyroid hormone Somatostatin Growth hormone Testosterone

The correct answer is prolactin. Prolactin has no peripheral gland hormone so there is no ability to exert long-loop negative feedback in its axis. PRL is tonically inhibited by hypothalamic dopamine. Prolactin increases dopamine thereby inhibiting its own secretion -In a short-loop negative feedback fashion. TSH has TH which feeds back on both hypothalamus and pituitary. Neither oxytocin nor ADH have these feedback loops as they're regulated by other signals, not long-loop feedback of their own concentrations in plasma.

Question 35 1 / 1 pts Secretion of which of the following pituitary hormones is regulated by a short-loop negative feedback? Antidiuretic hormone Luteinizing hormone Prolactin Oxytocin Thyroid stimulating hormone

The correct answer is dopamine. Dopamine inhibits the secretion of prolactin, which unlike all other anterior pituitary hormones will secrete even without other hypothalamic hormone involvement, unless slowed or even stopped by dopamine. All the other hormones stimulate their target tissues into action.

Question 36 1 / 1 pts Which of the following hormones has an inhibitory effect on its primary target tissue? Dopamine Thyroid-stimulating hormone Growth hormone Oxytocin Gonadotropin-releasing hormone

The correct answer is growth hormone. The growth spurt of puberty is associated with the highest secretion of growth hormone in a typical person's life. None of the other choices have such a clear life-cycle-dependent change in activity.

Question 37 1 / 1 pts Which of the following hormones is most likely to reach its peak concentrations over a lifetime between the ages of 10 to 14? Vasopressin Oxytocin Insulin Growth hormone Prolactin

The correct answer is luteinizing hormone. The basophils of the pituitary gland produce several of important hormones like FSH and LH (luteinizing hormone). Of the remaining four, only one is made by the pituitary (prolactin), and that is by an acidophil.

Question 38 1 / 1 pts Which of the following hormones is made by a basophil within the pituitary gland? Testosterone Thyroid hormone Prolactin Luteinizing hormone Epinephrine

The correct answer is growth hormone. Within the anterior pituitary, there are 5 distinct cell types which can be classified according to the hormone they secrete & the cells staining properties (acidophils stain pink, basophils stain blue): Lactotropes -PRL -acidophil Somatotropes -GH -acidophil Coricotropes -ACTH -basophil Thyrotropes -TSH -basophil Gonadotropes -FSH/LH -basophil Oxytocin is released by magnocellular neurons into the posterior pituitary

Question 10 1 / 1 pts Which of the following hormones is most likely produced by an acidophil within the pituitary gland? Adrenocorticotropic hormone Luteinizing hormone Oxytocin Thyroid stimulating hormone Growth hormone

The correct answer is antidiuretic hormone. The two hormones produced by hypothalamic magnocellular neurons are oxytocin & anti- diuretic hormone (ADH, also called vasopressin). The hypothalamic releasing & inhibiting hormones (CRH, GnRH, GHRH, GHIH, dopamine, TRH) are synthesized & released from hypothalamic parvocellular neurons. FSH is produced by anterior pituitary gonadotropes.

Question 11 1 / 1 pts Which of the following hormones is most likely synthesized & released from a hypothalamic magnocellular neuron? Growth hormone releasing hormone Dopamine Somatostatin Antidiuretic hormone Follicle stimulating hormone

The correct answer is growth hormone. Somatotrope cells are acidophilic cells in the anterior pituitary that secrete growth hormone. FSH & LH are synthesized in gonadotropes, ACTH in corticotropes, TSH in thyrotropes & PRL in lactotropes.

Question 12 1 / 1 pts Which of the following hormones is most likely synthesized & released from anterior pituitary somatotrope cells? Adrenocorticotropic hormone Prolactin Follicle stimulating hormone Thyroid stimulating hormone Luteinizing hormone Growth hormone

The correct answer is dopamine. Anterior pituitary lactotropes secrete prolactin. PRL secretion is under tonic inhibitory control by dopamine, which is the primary regulator od PRL release. GHIH inhibits somatotrope GH release TRH stimulates thyrotrope TSH release Oxytocin is released from the posterior pituitary & targets the uterus & breast. CRH stimulates ACTH release from anterior pituitary corticotropes.

Question 13 1 / 1 pts Which of the following hormones has lactotropes as a primary target? GHIH Dopamine Corticotrophin releasing hormone Oxytocin Prolactin Thyroid releasing hormone

The correct answer is e. Dopamine is a catecholamine; all other hypothalamic & anterior pituitary hormones are protein hormones. FSH, LH, TSH (& placental hCG) are further classified as glycoproteins -proteins which contain oligosaccharide chains (glycans) covalently attached to amino acid side-chains. These hormones have α and β subunits -the alpha subunit is identical for TSH, LH, FSH & hCG, but the β subunits are distinct. The β subunit confers hormone specificity.

Question 14 1 / 1 pts To which chemical classes of hormone do dopamine, prolactin, GHIH and FSH belong? D A B E C

The correct answer is a. Oxytocin receptor is a Gq GPCR & binding of OXT to its receptor in uterine smooth muscle stimulates contraction. In breast, it stimulates milk ejection (not production -prolactin does this). In C and D, the receptor name is wrong. ADH binds to V1 (Gq GPCR) on vascular smooth muscle cells stimulating an increase in Ca2+ and smooth muscle contraction leading to constriction of blood vessels. ADH binds to V2 (Gs GPCR) in kidney principal cells, increased cAMP & PKA leading to insertion of aquaporin channels into the apical/luminal membrane, stimulating water reabsorption.

Question 15 1 / 1 pts Relating to the attached table, which of the following combinations of target tissue, receptor subtype, signaling mechanism and physiological effect is accurate? D C B E A

The correct answer is plasma osmolarity greater than 290 mosm/l. The primary purpose of ADH is to ensure sufficient levels of water in the body to ensure normal osmolarity, blood volume & pressure. A major stimulus for ADH release is an increase in ECF osmolarity. Other stimuli for ADH include decreased stretch of the atria indicating a low blood volume and decreased blood pressure. Decreased sodium concentration would result in decreased ECF osmolarity which would inhibit ADH release.

Question 16 1 / 1 pts Which of the following will result in an increase in ADH secretion from the posterior pituitary? Increased stretch of the atrial wall Blood volume greater than 5.5 L Decreased ECF sodium concentration Plasma osmolarity greater than 290 mOsm/L Blood pressure greater than 140/80 mmHg

The correct answer is calmodulin. Flashback to M1 and M2 material Oxytocin binds to its Gq GPCR, activating PLC, leading to increased IP3 stimulates calcium release from the SR. Calcium binds calmodulin and this complex activates myosin light chain kinas which phosphorylates myosin light chain leading to contraction. Troponin C is not found in smooth muscle, it is in skeletal muscle. Synaptotagmin is a calcium binding protein on synaptic vesicles in the pre- synaptic terminal of the NMJ. nAChR are found in autonomic ganglia & post-synaptic membrane (motor end plate) of NMJ -not smooth muscle. Activation of MLCP will result in relaxation, not contraction of smooth muscle.

Question 17 1 / 1 pts In uterine smooth muscle cells, binding of oxytocin to its receptor results in uterine contraction. Through activation of which of the following proteins in uterine smooth muscle cells is contraction most likely mediated? Myosin light chain phosphatase Calmodulin Troponin C Synaptotagmin Nicotinic acetylcholine receptor

The correct answer is c. Flashback to M1 material Excess ADH (as in SIADH - syndrome of inappropriate ADH secretion) results in excessive retention of water by the kidneys. This results in an increase in ECF volume but a decrease in ECF osmolarity (adding water in excess of solute). Water moves into cells (water loves osmoles), increasing ICF volume and decreasing ICF osmolarity.

Question 18 1 / 1 pts In an individual with excess secretion of ADH, what will most likely happen to ECF and ICF volume and osmolarity? D A E B C

misskeyed (correct answer should be D)

Question 19 0 / 1 pts Which of the following changes in blood osmolarity, urine volume and urine osmolarity might you expect in a patient with SIADH? F E A D C B

The correct answer is c. GHRH stimulates GH release by binding to its Gs GPCR on somatotropes. Activation of Gs results in adenylate cyclase activity and increased cAMP levels. GHIH receptor on somatotropes is a Gi GPCR. Binding to this receptor decreases adenylate cyclase activity & cAMP levels, resulting in decreased GH release.

Question 26 1 / 1 pts Relating to the attached table, which of the following combinations of hormone, signaling mechanism and physiological effect is accurate in reference to growth hormone secretion from somatotropes? E B A D C

The correct answer is hypothalamic neurons. Antidiuretic hormone (ADH) is released from the hypothalamic neurons that project through the infundibulum. These neurons terminate in the posterior pituitary, where they release the hormones into the inferior hypophyseal venous plexus. Acidophils is incorrect because acidophils consist of somatotrophs and mammotrophs, which produce growth hormone and prolactin. Corticotrophs produce adrenocorticotropic hormone, not ADH. Thyrotrophs produce TSH in the anterior pituitary and do not have an effect on ADH release.

Question 2 1 / 1 pts A patient presents with excessive urination. He appears dehydrated even though he admits to drinking more than 4 L of water a day. The clinician conducts a test to determine whether the problem is in the brain or in the kidneys and concludes that inadequate amounts of antidiuretic hormone (ADH) are being released. Which of the following cells most likely secretes ADH in the pituitary system? Thyrotrophs Corticotrophs Acidophils Hypothalamic neurons

The correct answer is b. Flashback to M1 material Neurogenic Diabetes insipidus results from hyposecretion of ADH. Without ADH, water is lost in urine and not reabsorbed sufficiently. As such, water is lost from the body in excess of solute. ECF volume decreases, ECF osmolarity increases. "Water loves osmoles", so water will leave cells decreasing ICF volume and this will increase ICF osmolarity. q12_fb.png

Question 20 1 / 1 pts Select the Darrow-Yannet diagram which best represents the ECF and ICF volumes and osmolarities of an individual with new onset, untreated neurogenic Diabetes Insipidus (solid lines represent normal). q12.png C E B A D

The correct answer is Gs GRCR. Insufficient ADH is seen in Diabetes insipidus. Patient present with excess urine formation & excessive thirst. In the kidneys, ADH normally binds to V2 receptors which are Gs protein coupled receptors stimulating insertion of aquaporin-2 channels into the apical/luminal membrane, thus facilitating water reabsorption from fluid destined for urine and back into the blood. ADH/vasopressin can also bind V1 receptors in vascular smooth muscle -these are Gq GPCR and binding stimulates smooth muscle contraction & blood vessel constriction.

Question 21 1 / 1 pts A patient presents with polyuria and polydipsia. Blood glucose levels are normal, but urine osmolarity is decreased. A diagnosis of insufficient vasopressin is made. To what type of receptor does vasopressin normally act in the kidneys to stimulate water reabsorption? Aquaporin 2 channels Gq GPCR Nicotinic acetylcholine receptors Gs GRCR Nuclear receptors Vasopressin is also called ADH. Gi GPCR

The correct answer is dopamine. Prolactin is the primary hormone involved with milk production. It is under tonic inhibition by dopamine, so decreased dopamine is required for PRL to increase and stimulate milk production. Oxytocin stimulates milk ejection from the breast through binding to its Gq GPCR and stimulating contraction of myoepithelail cells in the breast. Pituitary ACTH & hypothalamic GHIH do not play a role on lactation.

Question 22 1 / 1 pts In a lactating woman, a decrease in which hormone is required to permit the mammary gland epithelium to produce milk? Dopamine ACTH Oxytocin Prolactin GHIH

The correct answer is administration of a dopamine agonist. Excess PRL often results from a prolactin producing tumor (prolactinoma). It is a relatively common endocrine disorder. Prolactin is under tonic inhibitory control by dopamine. Inhibiting dopamine production, blockage of dopamine receptors, administration of a dopamine antagonist or stimulation of prolactin production would make the situation worse. A dopamine agonist would mimic dopamine effect & decrease PRL release. Blocking PRL receptors would prevent PRL having an effect at the breast, but it would not treat the underlying cause of the problem (XS PRL production)

Question 23 1 / 1 pts Excess prolactin production can result in galactorrhea (breast milk production in a non-lactating individual). Based on your knowledge of the physiological control of prolactin secretion, which of the following mechanisms of action would be the most useful pharmacotherapy in the treating the underlying cause of galactorrhea? Stimulation of prolactin production Administration of a dopamine antagonist Blockage of dopamine receptors Administration of a dopamine agonist Inhibition of dopamine production Blockage of prolactin receptors

The correct answer is Jak/Stat-linked cytokine receptor. Excess prolactin stimulation of its receptor in breasts results in milk production. PRL receptor is a Jak/Stat-linked cytokine receptor, as is the receptor for GH. All other hypothalamic & pituitary hormones have GPCR (Gi, Gq or Gs). Insulin and IGFs bind receptor tyrosine kinases, while steroid hormones and thyroid hormones (T3, T4) bind intracellular receptors. Excess PRL will decrease GnRH and as such LH & FSH reducing fertility and libido in males and altering menstrual cycles in females. XS PRL is a common cause of infertility. The headaches & vison disturbance were a result of the prolactinoma enlarging and pushing on brain structures.

Question 24 1 / 1 pts A 34-year-old female presents with complaints of headache and blurred vision. She is concerned because she hasn't had a menstrual period for 10 months but has noticed discharge from her breasts. She has never been pregnant. Urinary hCG is negative, serum prolactin levels measure at 210 ng/mL (normal less than 20 ng/mL). Over stimulation of which type of receptor is causing the milky discharge? Gs GPCR Gi GPCR Gq GPCR Receptor tyrosine kinase Intracellular receptor Jak/Stat-linked cytokine receptor

The correct answer is prolactin. Disruption of blood flow through the hypophyseal portal system will disrupt delivery of hypothalamic releasing & inhibiting hormones to the anterior pituitary. As such, secretion of FSH, LH, ACTH, CRH & GH will be decreased. Secretion of downstream hormones estrogen, progesterone, testosterone, cortisol, thyroid hormone etc, will also be decreased. PRL is under tonic inhibition by dopamine. Removal of this inhibition increases PRL secretion. ADH and oxytocin do not travel in the hypophyseal portal blood vessels. Instead, the hypothalamic neurons which produce them travel through the infundibulum (pituitary stalk) have terminal endings in the posterior pituitary. Cutting the stalk will suppress secretion of these hormones for a short time, after which the cut end of the nerves still retained in the hypothalamus secrete the hormones once again at normal levels. However, the secr

Question 25 1 / 1 pts A study is conducted to examine the role of the hypothalamus in controlling pituitary function. In experimental animals, the pituitary stalks are ligated to interrupt the hypophyseal portal blood flow. An increase in circulating levels of which hormone is likely to occur as a result of this procedure? Prolactin Cortisol Luteinizing hormone Thyroid hormone Growth hormone Anti-diuretic hormone

The correct answer is "GHRH stimulates GH. GH stimulates GHIH and IGF. IGF and GHIH inhibit GH." GH is stimulated by GHRH and inhibited by GHIH. GH stimulates IGF which feeds back at the level of the pituitary only, decreasing GH -long loop negative feedback. GH also stimulates production of GHIH which inhibits further GH release -short loop negative feedback. A is also correct, but does not tell the full story. As such, "GHRH stimulates GH. GH stimulates GHIH and IGF. IGF and GHIH inhibit GH" is the better answer.

Question 27 1 / 1 pts Relating to the regulation of growth hormone (GH), which of the following statements accurately reflects the feedback loops controlling GH release? GHRH stimulates GH. GH stimulates GHIH and IGF. IGF and GHIH inhibit GH. GHIH stimulates GH. GH stimulates IGF. IGF stimulates GH. GHRH stimulates GH. GH stimulates GHRH and IGF. IGF inhibits GH and GHRH. GHRH stimulates GH. GH stimulates IGF. IGF inhibits GH. GnRH stimulates GH. GH stimulates IGF. IGF inhibits GnRH and GH.

The correct answer is ghih. GHIH (somatostatin, growth hormone inhibiting hormone) is effective in reducing excess secretion of GH and it can also reduce tumor size. GHRH would increase GH release. Excess GH is the problem in acromegaly, so administering GH would make the problem worse. GnRH control LH & FSH levels, no impact on GH release. Glucagon is released by pancreatic alpha cells in respond to low blood sugar. Again, it has no effect on GH release from the pituitary Somatotropes. Glucocorticoids (e.g. cortisol) would feedback to inhibit the hypothalamic-pituitary-adrenal axis but have little effect on GH release.

Question 28 1 / 1 pts A 50-year-old man presents to his physician with complaints about his appearance. It has been 10 years since his last visit. His hands and feet have grown larger, his jaw is protruding. He complains of fatigue and erectile dysfunction. His blood glucose levels are high. MRI reveals a 1.5 cm mass on the anterior pituitary. While awaiting surgery, which treatment would provide the greatest therapeutic benefit to this patient? Glucocorticoids GH GHRH Glucagon GnRH GHIH

The correct answer is growth hormone. GH receptor like that for PRL is a Jak-Stat linked cytokine receptor. Cortisol & thyroxine (T4) act through intracellular receptors. ADH acts through V1 and V2, both of which are GPCRs (V1 -Gq GPCR, V2 Gs GPCR) IGF-1 receptor is a receptor tyrosine kinase

Question 29 1 / 1 pts A researcher is investigating the action of a hormone on its target tissue. She notices that the hormone is acting through the JAK-STAT second messenger system to exert its effects. Which of the following is the most likely identity of the hormone being studied? Antidiuretic hormone Thyroxine Growth hormone Insulin-like growth factor 1 Cortisol

The correct answer is secondary plexus. The thyroid is stimulated by TSH (thyroid-stimulating hormone), which is released by thyrotrophs. This patient is exhibiting symptoms of hypothyroidism. The low T4 stimulates the pituitary to increase the release of TSH. Thyrotrophs are a type of basophil, which reside in the anterior pituitary. The anterior pituitary is supplied directly by the secondary plexus of the portal veins. Blood leaves the secondary plexus through the anterior hypophyseal veins. The inferior hypophyseal artery forms its own separate capillary plexus only in the posterior lobe. The superior hypophyseal artery forms the primary plexus around the infundibulum.

Question 3 1 / 1 pts A 30-year-old female presents with fatigue, mild hair loss, and dry skin. On blood tests, she is found to have an elevated thyroid-stimulating hormone and a low T4. Which of the following directly supplies the cells that release the hormone responsible for stimulating the thyroid? Inferior hypophyseal artery Anterior hypophyseal veins Secondary plexus Primary plexus

The correct answer is somatomedins. Growth hormone is secreted in pulsatile fashion, with a large burst occurring during deep sleep. Growth hormone secretion is increased by sleep, stress, puberty, starvation, and hypoglycemia. Somatomedins (IGFs) are generated when growth hormone acts on its target tissues; they inhibit growth hormone secretion by the anterior pituitary. GH levels are lower in older individuals, reaching a peak around puberty.

Question 30 1 / 1 pts Which of the following inhibits the secretion of growth hormone by the anterior pituitary? Stress Puberty Somatomedins Starvation Hypoglycemia Sleep

The correct answer is E. GH is lipolytic(breaks down fat), protein anabolic (increased amino acid uptake in muscles and protein synthesis in liver & muscle) and diabetogenic(increases blood glucose levels by stimulating hepatic gluconeogenesis & inhibiting glucose uptake to adipose tissue and muscle). It acts to decrease fat mass & increase lean body mass. Glucose spilling out into blood is used to supply energy for growth...

Question 31 1 / 1 pts GH exerts a direct effects when it binds to its receptor in adipose tissue, liver and skeletal muscle. Relating to the attached table, which of the following changes accurately reflect physiological effects of GH action? D B E C A

The correct answer is receptor tyrosine kinase. This patients' symptoms and signs are consistent with acromegaly, caused by excess GH. GH binds to its Jak/Stat linked receptor in the liver and stimulates hepatic production of IGF-1. IGF-1 mediates the growth promotion effects of GH by binding to its receptor tyrosine kinase in cartilage and bone, leading to enlargement f the jaw, protrusion of the chin and lower teeth, thickening of the skull and bony protrusions over the eye. Remember, GH effects on growth are indirect and mediated via IGFs. GHRH acts through Gs GPCRs, GHIH acts through Gi GPCRs. Intracellular receptors are for steroid hormones and thyroid hormones. None of the Growth hormone axis act through Gq GPCRs; GnRH & TRH have this receptor type.

Question 32 1 / 1 pts A 41-year-old female presents to her physician with complaints that her friends have commented that her appearance has changed. Her facial features have become coarse, her lower jaw is protruding, and her teeth have separated. Her feet and hands have enlarged, her rings and shoes no longer fit. Over stimulation of which of the following receptor types is most likely directly responsible for the patient's complaints? Jak-stat linked cytokine receptor Gi GPCR Gq GPCR Gs GPCR Receptor tyrosine kinase Intracellular receptor

The correct answer is IGF-1. Only Insulin-like growth factor 1 which is part of the insulin family of related hormones, has a receptor that uses tyrosine kinase just like insulin. ACTH and TSH both use cyclic AMP (Gs GPCRs), GH uses JAK-STAT, and thyroxine (T4) doesn't use a second messenger system at all, it enters the cells and binds intracellular receptors.

Question 33 1 / 1 pts Which of the following hormones exerts its effects through a tyrosine kinase second messenger system? ACTH Thyroxine TSH GH IGF-1

The correct answer is gnrh. GnRH stimulates a set of basophils called gonadotrophs to secrete LH and FSH, which during a part of the ovarian cycle results in production and secretion of estrogen & progesterone into the blood. Both progesterone and estrogen provide feedback to the hypothalamus and pituitary. Progesterone feedback is always negative, estrogen feedback can be negative or positive, depending on the stage of the menstrual cycle. GHRH stimulates GH, CRH stimulates ACTH, DA inhibits PRL, and TRH stimulates TSH & none of these have direct stimulatory effects on ovarian estrogen production. At high levels, PRKL can inhibit GnRH which will lead to decreased LH/FSH decreased ovarian hormone production....

Question 39 1 / 1 pts In a healthy 33-year-old female, which of the following hypothalamic hormones is most likely to result in secretion of estrogen into the plasma? TRH DA GHRH GnRH CRH

The correct answer is hypothalamus; posterior pituitary. Oxytocin is produced in the nerve cell bodies of the hypothalamus. It travels through the infundibulum to the nerve endings in the posterior pituitary, where it is stored. Although the hypothalamus is the correct location of oxytocin production, the anterior pituitary and pars intermedia never store oxytocin, so hypothalamus; anterior pituitary and hypothalamus; pars intermedia are incorrect. The pars intermedia is a third area located between the anterior and posterior pituitary. The infundibulum is not the site of oxytocin production. Instead, it houses the neuroendocrine axons that allow oxytocin to be transported from the hypothalamus to the posterior pituitary. Therefore, infundibulum; pars intermedia and infundibulum; posterior pituitary are incorrect.

Question 4 1 / 1 pts A 27-year-old female is in labor, and a large amount of oxytocin is released into systemic circulation. Before being released, where is oxytocin produced and stored, respectively? Hypothalamus; anterior pituitary Infundibulum; pars intermedia Infundibulum; posterior pituitary Hypothalamus; pars intermedia Hypothalamus; posterior pituitary

The correct answer is pars distalis. The pars distalis is the largest and most prominent part of the adenohypophysis. It is responsible for producing and secreting most of the hormones of the anterior pituitary, including growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin (PRL). Its size and hormone-producing function make it the dominant region of the adenohypophysis. The pars nervosa is actually part of the posterior pituitary (neurohypophysis), not the adenohypophysis. The pars nervosa is involved in the storage and release of hormones like oxytocin and vasopressin (antidiuretic hormone), which are produced in the hypothalamus. The median eminence is a region of the hypothalamus near the base and in close relation to the infundibular stalk, not the adenohypophysis. The pars tuberalis is a relatively

Question 5 1 / 1 pts Which of the following is the largest portion of the adenohypophysis? Median eminence Pars nervosa Pars tuberalis Pars distalis Pars intermedia

The correct answer is lactotrope. Lactotropes (mammotropes) are a type of acidophil cells in the anterior pituitary gland that specifically secretes prolactin. Prolactin is a hormone involved in milk production and lactation in mammals. The acidophil cell in the anterior pituitary that typically stain with acidic dyes include both lactotropes (which secrete prolactin) and somatotropes (which secrete growth hormone). Corticotropes are cells in the anterior pituitary that secrete adrenocorticotropic hormone (ACTH). ACTH stimulates the adrenal cortex to produce cortisol and other hormones. Corticotropes are classified as basophils, not acidophils. Gonadotropes secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones are involved in regulating reproductive processes. Gonadotropes are also basophils, not acidophils. Somatotropes secrete growth hormone (GH). While somatotropes are indeed acid

Question 6 1 / 1 pts Which of the following is an acidophil that secretes prolactin? Somatotrope Corticotrope Lactotrope Thyrotrope Gonadotrope

The correct answer is sella turcica. The sella turcica is a bony depression in the sphenoid bone of the skull that houses the pituitary gland. Its name, which means "Turkish saddle" in Latin, describes its saddle-like shape. The pituitary gland sits within this depression, making it a critical osteological feature for protecting and supporting the pituitary gland. The frontal bone is located at the front of the skull, forming the forehead and the upper part of the eye sockets. It does not contain or house the pituitary gland. Instead, it is far from the location of the sella turcica, which is more centrally located at the base of the skull. The ethmoid bone is located between the eyes and forms part of the nasal cavity and the medial walls of the orbits. While it plays a role in the structure of the nasal cavity and the orbit, it does not house the pituitary gland. The coronal suture is a fibrous joint that connects

Question 7 1 / 1 pts The pituitary gland sits in which of the following structures/features? Frontal bone Sella Turcica Coronal suture Ethmoid bone Mastoid process

The correct answer is pinealocytes. Pinealocytes are the primary cells in the pineal gland responsible for producing and secreting melatonin. Melatonin is a hormone that regulates the sleep-wake cycle and circadian rhythms. Pinealocytes release melatonin in response to darkness, helping to induce sleep. The corpora arenacea are calcified deposits within the pineal gland, often referred to as "brain sand." While they are found in the pineal gland, they do not secrete hormones. Their presence is associated with aging and calcification, but they have no role in hormone production. Parafollicular cells, also known as C cells, are located in the thyroid gland and are responsible for producing calcitonin, a hormone involved in calcium homeostasis. They are not involved in the production of melatonin. Thyrotropes are cells in the anterior pituitary gland that secrete thyroid-stimulating hormone (TSH). They play a role in re

Question 8 1 / 1 pts A 34-year-old woman presents to her primary care physician with complaints of insomnia and difficulty maintaining a regular sleep-wake cycle. After discussing her symptoms, the physician suspects a disruption in her circadian rhythms. The physician decides to assess the function of a small gland in the brain that is known to regulate sleep patterns by secreting a particular hormone. Which of the following is responsible for secreting this hormone? Pituicytes Thyrotropes Parafollicular cells Pinealocytes Corpora arenacea

The correct answer is corticotropin releasing hormone. The 6 hypothalamic releasing and inhibiting hormones (CRH, GHRH, GnRH, TRH, Dopamine & GHIH) are all released from parvocellular neurons at the median eminence and enter the hypophyseal portal system from where they are transported to the anterior pituitary. ADH & Oxytocin travel in magnocellular neurons to the posterior pituitary directly. GH and TSH are synthesized in the anterior pituitary somatotropes and are released directly into the systemic circulation.

Question 9 1 / 1 pts Which of the following hormones is most likely to be released at the median eminence to enter the hypophyseal portal system? Thyroid stimulating hormone Anti-diuretic hormone Corticotropin releasing hormone Oxytocin Growth hormone

The correct answer is acidophil cells. Acidophils stain with eosin and appear pink. They produce growth hormone and prolactin. Basophil cells stain with hematoxylin and appear bluish purple. They produce follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, and thyroid-stimulating hormone. Chromophobe cells do not stain well with either hematoxylin or eosin and have a pale appearance. They do not produce any hormones. Oxyphil cells are present in the parathyroid gland and are large cells with abundant, eosinophilic cytoplasm that occur in clusters; their function is unknown.

Which of the following types of cells produce growth hormone and prolactin? Chromophobe cells Oxyphil cells Basophil cells Acidophil cells