BIO 202 Lesson 1

Question 0

Nearly all hormones can be classified as…

Answer 0

They can be classified chemically as either amino acid based or steroids.

Most hormones are a amino acid based.

Steroids are synthesized from cholesterol . Of the hormones produced by major endocrine organs, only gonadal and adrenocortical hormones are steroids.

Question 1

Compare and contrast endocrine and exocrine glands.

Answer 1

Exocrine: produce non hormonal substances such as sweat and saliva, and have ducts through which these substances are routed to a membrane surface.

Endocrine: also called ductless glands produce hormones and lack ducts. They release their hormones into the surrounding tissue fluid and they typically have a rich vascular and lymphatic drainage that receives their hormones.

Include
pituitary (securely seated in the sella turcica of the sphenoid bone), thyroid (located in the anterior neck, on the trachea just inferior to the larynx), parathyroid (nearly hidden from view in the posterior aspect of the thyroid gland), adrenal (perched atop the kidneys) pineal (hangs from the roof of the third ventricle in the diencephalon), and thymus glands (located deep to the sternum in the thorax).

Hypothalamus, along with its neural functions, produces and releases hormones, so it can be considered a neuroendocrine organ.

Organs such as the pancreas and gonads (ovaries and testes), are also major endocrine glands.

Question 2

A hormonal stimulus typically produces one or more of what changes?

Answer 2

1. Alters plasma membrane permeability or membrane potential, or both, by opening or closing ion channels.
2. Stimulates synthesis of proteins or regulatory molecules such as enzymes within the cell
3. Activates or deactivates enzymes
4. Induces secretory activity
5. Stimulates mitosis

Question 3

What are the two main mechanisms I that account for how a hormone communicates with its target cell ( how hormone receptor binding is harnessed to the intracellular machinery needed for hormone action)?

Answer 3

The mechanism used depends on the chemical nature of the hormone and the cellular location of the receptor.

*The Cyclic AMP Signaling Mechanism: this mechanism involves the interaction of three plasma membrane comments to determine intracellular levels of cyclic AMP (cAMP) - a hormone receptor, a signal transducer (a G protein), and an effector enzyme (adenylate cyclase)

Pg.607

*The PlP-Calcium Signal Mechanism: intracellular calcium ions act as the final mediator

Pg. 609

Question 4

A hormone receptor responds to hormone binding by prompting the cell to perform, or turn on, some gene-determining “preprogrammed “ function. Hence hormones are molecular triggers rather than informational molecules. Although binding of a hormone to a receptor is the crucial first step, target cell activation by hormone-receptor interaction depends equally on what three factors?

Answer 4

1) blood levels of the hormone
2) relative numbers of receptors for that hormone on or in the target cells
3) affinity (strength) of the bond between the hormone and the receptor

All three factors change rapidly in response to various stimuli and changes within the body

Question 5

1. Up regulation

2. Down-regulation

Answer 5

1. Receptors are dynamic structures. In some instances target cells form more receptors in response to rising blood levels of the specific hormones to which they respond.
2. In other cases, prolonged exposure to high hormone concentrations desensitizes the target cells,so that they responded less vigorously to hormonal stimulation. This down-regulation involves loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.

Question 6

Three types of hormone interaction?

Answer 6

Permissiveness- the situation when one hormones cannot exert its full effects without another hormone being present.

Synergism- of hormones occurs I. Situations whee more than one hormone produces the same effects at the target cell and their combined effects are amplified.

Antagonism: when one hormone opposes the action of another hormone. Ex: insulin, which lowers blood glucose levels, is antagonized by the action of glucagon, which acts to raise blood glucose levels.

Question 7

The synthesis and release of most hormones are regulated by what?

Answer 7

Some type of negative feedback system

Question 8

Endocrine glands are stimulated to manufacture and release their hormones by what three major Types of stimuli?

Answer 8

1. Humoral- endocrine glands secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients. It is the simplest of the endocrine control systems. Include insulin produced by the pancreas, aldosterone one of the adrenal cortex hormones and blood calcium levels.
2. Neural- In a few cases nerve fibers stimulate hormone release. The classic example of neural stimuli is sympathetic nervous system stimulation of the adrenal medulla to release catecholamines (norepinephrine and epinephrine) during periods of stress.
3. Hormonal: many endocrine glands release their hormones in response to hormones produced by other endocrine organs, and the stimuli in these cases are called hormonal stimuli. For example, release of most anterior pituitary hormones is regulated by releasing and inhibiting hormones produced by the hypothalamus, and many anterior pituitary hormones in turn stimulate other endocrine organs to release their hormones.

Question 9

What makes certain adjustments to maintain homeostasis by overriding normal endocrine controls?

Answer 9

The nervous system.

Question 10

Pituitary gland has two major lobes; one is neural tissue and the other is glandular

Posterior pituitary is composed of what? And releases what?

The anterior pituitary is composed of what? And releases what?

Answer 10

Composed largely of pituicytes and nerve fibers and it releases neurohormones (hormones secreted by neurons) received ready-made from the hypothalamus. It is actually part of the brain.

Composed of glandular tissue and it manufactures and releases a number of hormones

Question 11

Hypothalamic-hypophyseal tract

Answer 11

Posterior lobe derives from a down growth of hypothalamic tissue and maintains it neural connection with the hypothalamus via a nerve bundle called the hypothalamic-hypophyseal tract which runs through the infundibulum. This tract arises from neurons in the supraoptic and paraventricular nuclei of the hypothalamus.

Question 12

After touching the posterior lobe, the anterior lobe loses its connection with the oral mucosa and adheres to the neurohypophysis. There is no direct neural connection between the anterior lobe and the hypothalamus, but there is a…

Answer 12

Vascular connection

Question 13

What makes up the hypophyseal portal system and what is it?

Answer 13

The primary and secondary capillary plexuses and the intervening hypophyseal portal veins make up the hypophyseal portal system.

Via this portal system, releasing and inhibiting hormones secreted by neurons in the ventral hypothalamus circulate to the adenohypophysis, where they regulate secretion of its hormones . All these hypothalamic regulatory hormones are amino acid based, but they vary in size from a single amine to peptides and proteins.

Question 14

What is the “master endocrine gland?”

Answer 14

Hypothalamus

Question 15

Growth hormones are produced by what and stimulate what?

Answer 15

Growth hormone is produced by cells called somatotropin of the anterior Lobe. Although GH stimulates most body cells to increase in sized and divide, it’s major targets are the bones and skeletal muscles

Question 16

Which hormone is more important in general as a regulatory factor and why?

Answer 16

The hypothalamic are more important than the inhibiting hormones because only very little hormone is stored by secretory cells of the anterior lobe.

Question 17

What pituitary hormones are tropics or tropic hormones (hormones that regulate the secretory action of other endocrine glands).

Answer 17

Thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, and luteinizing hormone. Except for growth hormones all affect their target cells via a cyclic AMP second-messenger system.

Question 18

What promotes protein synthesis and encourages the use of fats for fuel, conserving glucose?

Answer 18

Growth hormone (GH)

Question 19

Growth hormone is mediated by insulin-like growth factors (IGFs) also known As somatomedins. What are somatomedins?

Answer 19

A family of growth-promoting proteins produced by the liver, skeletal muscle, bone, and other tissues.

Question 20

Secretion of GH is regulated by chiefly two hypothalamic hormones with antagonistic effects. What are they?

Answer 20

• Growth hormone-releasing hormone (GHRH)- stimulates GH release
• growth inhibiting hormone (GHIH)- also called somatostatin, inhibits it.

Question 21

Thyroid stimulating hormone (TSH). Or thyrotropin

Answer 21

Tropic hormone that stimulates normal development and secretory activity of the thyroid gland. Triggered by the hypothalamic peptide thyrotropin-releasing hormone (TRH).

Question 22

Adrenocorticotropic hormone (ACTH)

Answer 22

Stimulates the adrenal cortex to release corticosteroid hormones, most importantly glucocorticoids that help the body resist stressors.

Question 23

Gonadotropins

Answer 23

Regulate the function of the gonads (ovaries and testes)

Question 24

Prolactin (PRL)

Answer 24

In women it stimulates milk production, in men it is unknown

Question 25

PRL release is stimulated by what?

Answer 25

It is stimulated by estrogen

Question 26

What does anti diuretic hormone (ADH) influence? What does oxytocin influence?

Answer 26

ADH influences body water balance and oxytocin stimulates the contraction of smooth muscle, particularly that of the uterus and breasts.

Question 27

Thyroid hormone (TH)

Answer 27

The body's major metabolic hormone. Actually two iodine-containing amine hormones: thyroxine or T4, and triiodothyronine or T3. Except for the adult brain spleen, testes, uterus, and thyroid gland itself, TH affects virtually every cell in the body. Also plays an important role in maintaining blood pressure. It is additionally an important regulator of tissue growth and development, normal skeletal and nervous system development and maturation for reproductive capabilities.

Question 28

Thyroid hormone synthesis involves six processes...

Answer 28

1. Formation and storage of thyroglobulin: after being synthesized on the ribosomes, thyroglobulin is transported to the Golgi apparatus, where sugar residues are attached and the molecules are packed into vesicles. These transport vesicles move to the apex of the follicle cell, where their contents are discharged into the follicle lumen and become part of the stored colloid. 2. Iodide trapping: to produce the functional iodinated hormones, the follicle cells must accumulate iodide (anions of oidine, I-) from the blood. Because the intracellular concentration of I- is over 30 times higher than that in blood, iodide trapping depends on active transport. Once trapped inside the follicle cell, iodide then moves into the follicle lumen by facilitated diffusion. 3. Oxidation to iodine and iodination: At the border of the follicle cell and colloid, iodides are oxidized (by removal of electrons) and converted to iodine (I2). Once formed, iodine is attached to tyrosine amino acids that form part of the thyroglobulin colloid. This iodination reaction occurs at the junction of the follicle cell apex and the colloid and is mediated by peroxidase enzymes. Attachment of one iodine to a tyrosine produces monoiodotyrosine (MIT or T1); attachment of the two iodine a produces diiodotyrosine (DIT or T2). 4. Coupling of T2 and T1: Next, enzymes in the colloid link T1 and T2 together. Two linked DITs result in T4; coupling of MIT and DIT produces T3. At this point, the hormones are still part of the thyroglobulin colloid. 5. Colloid endocytosis: hormone secretion requires that the follicle cells reclaim iodinated thyroglobulin by endocytosis and combine the vesicles with lysosomes. 6. Cleavage of the hormones for release: in the lysosomes, the hormones are cleaved out of the colloid by lysosomal enzymes. The hormones then Diffuse from the follicle cells into the bloodstream. The main hormonal product secreted is T4. Some T4 is converted to T3 before secretion but most T3 is generated in the peripheral tissues.

Question 29

Thyroid stimulating hormone (TSH) levels do what during the I the day, before sleep and during the night?

Answer 29

They are lower during the day, peak just before sleep, and remain high during the night.

Question 30

Which is more active, T3 or T4?

Answer 30

T3 binds more avidly and is about ten times more active.

Question 31

TH initiates what when it enters a target cell?

Answer 31

It initiates the transcription of mRNA after it binds to intracellular receptors within the cell's nucleus.

Question 32

1. Myxedema 2. Endemic or goiter 3. Cretinism 4. Graves' disease

Answer 32

1. A full-blown hypothyroid syndrome "mucous swelling." Symptoms include low metabolic rate, feeling chilled, constipation; thick, dry skin and puffy eyes; edema; legal thy; and mental sluggishness. 2. Results from lack of iodine, the thyroid enlarges and protrudes. 3. Hypothyroidism in infants where the child is mentally retarded and has a short disproportionately sized body and a thick tongue and neck. May reflect a genetic deficiency if the fatal thyroid gland or maternal factors, such as lack of dietary iodine. 4. Most common hyperthyroid pathology. Believed to be an autoimmune disease. Symptoms include an elevated metabolic rate, sweating; rapid irregular heartbeat, nervousness, and weight loss despite adequate food intake. Exophthalmos, protrusion of the eyeballs may occur if the tissue of the eyes becomes edema tours and then fibrous.

Question 33

Calcitonin

Answer 33

It's most important effect is to lower blood Ca2+ levels. A direct antagonist of parathyroid hormone produced by the parathyroid glands. Targets the skeleton and inhibits osteoclast activity; it has a bone-sparing effect. Excessive blood levels of Ca2+ act As a humoral stimulus for calcitonin release. Important in children when the skeleton grows quickly and the bones are changing dramatically in mass, size, and shape. In adults it is best a weak hypoglycemic agent.

Question 34

Parathyroid gland (PTH)

Answer 34

Single most important hormone controlling the calcium balance of the blood. It's release is triggered by falling blood Ca2+ levels and inhibited by hypercalcemia. PTH increases CA2+ levels in blood by stimulating three target organs: the skeleton ( which contains considerable amounts of calcium salts in its matrix), the kidneys, and the intestine. Stimulates the osteoclasts (bone-resorbing cells) to digest some of the bony matrix and release ionic calcium and phosphates to the blood, enhances reabsorption of Ca2+ ( and excretion of Po43- ) by the kidneys; and increases absorption of Ca2+ by the intestinal mucosal cells.

Question 35

Why is control of Ca2+ levels critical?

Answer 35

Because plasma calcium ion homeostasis is essential for so many functions including transmission of nerve impulses, muscle contraction, and blood clotting.

Question 36

Hyperparathyroidism Hypoparathyroidism

Answer 36

Rare and usually the result of a parathyroid gland tumor. Results in frail, breakable bones, depression of the nervous system, abnormal reflexes, formation of kidney stones as excess calcium salts precipitate in the kidney tubules, and calcium deposits may also form in soft tissues throughout the body and severely impair vital organ functioning a condition called metastatic calcification. PTH deficiency, increases the excitability of neurons and accounts for e classical symptomatic tetany such as loss of sensation, muscle twitches, and convulsions. Untreated, the symptoms progress to respiratory paralysis and death.

Question 37

Aldosterone

Answer 37

Main job is to maintain sodium ion balance. Where Na+ goes water follows - an event that leads to changes in blood volume and blood pressure. Hence Na+ regulation is important to overall body homeostasis. Also plays a role in cardiac regulation. Secretion if aldosterone is stimulated by rising blood levels of K+, low blood levels of Na+, and decreasing blood volume and blood pressure

Question 38

Four mechanisms regulate aldosterone secretion...

Answer 38

1) the renin-angiotensin 2) plasma concentrations of potassium and sodium ions 3) ACTH 4) atrial natriuretic peptide (ANP) Further explained Pg.628

Question 39

Hypersecretion of aldosterone results in..

Answer 39

Hypertension and edema due to excessive Na+ and water retention, and accelerated excretion of potassium ions. If K+ loss is extreme, neurons become nonresponsive and muscle weakness ( and eventually paralysis) occurs.

Question 40

Glucocorticoids

Answer 40

Influence the energy metabolism of most body cells and hello us to resist stressors. Under normal circumstances they help the body adapt to intermittent food intake by keeping blood glucose levels fairly constant and maintain blood pressure by increasing the action of vasoconstrictors. Glucocorticoid hormones include cortisol (hydrocortisone), cortisone, and corticosterone. Basic mechanism of activity in target cells is to modify gene activity. Secretion is regulated by negative feedback. Stress results in a dramatic rise in blood levels of glucose, fatty acids, and amino acids, all provoked by cortisol

Question 41

Excessive amounts of glucocorticoid may result in...

Answer 41

Inhibit inflammation by decreasing the release of inflammatory chemicals and preventing vasodilation, depress cartilage and bone formation, depress the immune system, and promote changes in cardiovascular, neural, and gastrointestinal function. May also result in Cushing's syndrome which is characterized by persistent hyperglycemia (steroid diabetes), dramatic losses in muscle and bone protein, and water and salt retention, leading to hypertension and edema. Signs of syndrome include a swollen "moon face", redistribution if fat to the abdomen and posterior neck, a tendency to bruise, and poor wound healing.

Question 42

Addison's disease

Answer 42

Involves deficits in both glucocorticoids and mineralocorticoids. Its victims tend to lose weight; their plasma glucose and sodium levels drop and potassium levels rise. Severe dehydration and hypotension are common.

Question 43

Gonadocorticoids (sex hormone)

Answer 43

Secreted by the adrenal cortex as weak androgens which are later converted to either estrogen or testosterone.

Question 44

Hyper secretion of gonadocorticoids results in....

Answer 44

Adrenogenital syndrome where the effects can cause the masculinization of a female.

Question 45

Epinephrine Norepinephrine

Answer 45

More potent stimulator of metabolic activities bronchial dilation, and increased blood flow to skeletal muscles and the heart. Greater influence on peripheral vasoconstriction and blood pressure.

Question 46

The director of the stress response is the...

Answer 46

Hypothalamus

Question 47

Hormones of the adrenal medulla; imbalance of these...

Answer 47

Deficient: they merely intensify activities set into motion by the sympathetic nervous system neurons so a deficit In these is not a problem. Excess: hypersecretion of catecholamines produces symptoms of uncontrolled sympathetic nervous system activity-hyperglycemia, increased metabolic rate, rapid heartbeat and palpitations, hypertension, intense nervousness and sweating.

Question 48

Pancreas

Answer 48

Located partially behind the stomach in the abdomen, a mixed gland composed of both endocrine and exocrine gland cells.

Question 49

Insulin and glucagon, hypo or hyperglycemic

Answer 49

Insulin is hypoglycemic Glucagon is hyperglycemic

Question 50

Glucagon

Answer 50

Sympathetic nervous system stimulation and rising amino acid levels stimulate its release Rising blood glucose levels, insulin, and somatostatin suppress its release.

Question 51

After glucose enters a target cell, insulin binding triggers enzymatic activities that...

Answer 51

1) catalyze the oxidation of glucose for ATP production 2) join glucose molecules together to form glycogen 3) convert glucose to fat (particularly in adipose tissue)

Question 52

Insulin

Answer 52

Sweeps glucose out of the blood, causing it to be used for energy or converted to other forms (glycogen or fats), and it promotes protein synthesis and fat storage.

Question 53

Insulin and what are the hypoglycemic factors that counterbalance the many hyperglycemic hormones?

Answer 53

Somatostatin

Question 54

Pineal gland

Answer 54

Hangs from the roof of the third ventricle in the diencephalon. Major secretory product of melatonin which affects our biological clock and timing of pubertal development.

Question 55

Thymus gland

Answer 55

Locate deep to the sternum in the thorax. The major hormonal product of the thymus epithelial cells is a family of peptide hormone, including thymopoietins, thymic factor, and thymosins which appear to be essential for the normal development of T lymphocytes and the immune response.

Question 56

Other hormone-producing cells occur in various organs of the body, including...

Answer 56

Heart, gastrointestinal tract, placenta, kidneys, skin, adipose tissue Pg. 637

Question 57

A hormone receptor responds to hormone binding by prompting the cell to perform, or turn on, some gene-determining "preprogrammed " function. Hence hormones are molecular triggers rather than informational molecules. Although binding of a hormone to a receptor is the crucial first step, target cell activation by hormone-receptor interaction depends equally on what three factors?

Answer 57

1) blood levels of the hormone 2) relative numbers of receptors for that hormone on or in the target cells 3) affinity (strength) of the bond between the hormone and the receptor All three factors change rapidly in response to various stimuli and changes within the body

Question 58

1. Up regulation | 2. Down-regulation

Answer 58

1. Receptors are dynamic structures. In some instances target cells form more receptors in response to rising blood levels of the specific hormones to which they respond. 2. In other cases, prolonged exposure to high hormone concentrations desensitizes the target cells,so that they responded less vigorously to hormonal stimulation. This down-regulation involves loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.

Question 59

Three types of hormone interaction?

Answer 59

Permissiveness- the situation when one hormones cannot exert its full effects without another hormone being present. Synergism- of hormones occurs I. Situations whee more than one hormone produces the same effects at the target cell and their combined effects are amplified. Antagonism: when one hormone opposes the action of another hormone. Ex: insulin, which lowers blood glucose levels, is antagonized by the action of glucagon, which acts to raise blood glucose levels.

Question 60

The synthesis and release of most hormones are regulated by what?

Answer 60

Some type of negative feedback system

Question 61

Endocrine glands are stimulated to manufacture and release their hormones by what three major Types of stimuli?

Answer 61

1. Humoral- endocrine glands secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients. It is the simplest of the endocrine control systems. Include insulin produced by the pancreas, aldosterone one of the adrenal cortex hormones and blood calcium levels. 2. Neural- In a few cases nerve fibers stimulate hormone release. The classic example of neural stimuli is sympathetic nervous system stimulation of the adrenal medulla to release catecholamines (norepinephrine and epinephrine) during periods of stress. 3. Hormonal: many endocrine glands release their hormones in response to hormones produced by other endocrine organs, and the stimuli in these cases are called hormonal stimuli. For example, release of most anterior pituitary hormones is regulated by releasing and inhibiting hormones produced by the hypothalamus, and many anterior pituitary hormones in turn stimulate other endocrine organs to release their hormones.

Question 62

What makes certain adjustments to maintain homeostasis by overriding normal endocrine controls?

Answer 62

The nervous system.

Question 63

Pituitary gland has two major lobes; one is neural tissue and the other is glandular Posterior pituitary is composed of what? And releases what? The anterior pituitary is composed of what? And releases what?

Answer 63

Composed largely of pituicytes and nerve fibers and it releases neurohormones (hormones secreted by neurons) received ready-made from the hypothalamus. It is actually part of the brain. Composed of glandular tissue and it manufactures and releases a number of hormones

Question 64

Hypothalamic-hypophyseal tract

Answer 64

Posterior lobe derives from a down growth of hypothalamic tissue and maintains it neural connection with the hypothalamus via a nerve bundle called the hypothalamic-hypophyseal tract which runs through the infundibulum. This tract arises from neurons in the supraoptic and paraventricular nuclei of the hypothalamus.

Question 65

After touching the posterior lobe, the anterior lobe loses its connection with the oral mucosa and adheres to the neurohypophysis. There is no direct neural connection between the anterior lobe and the hypothalamus, but there is a...

Answer 65

Vascular connection

Question 66

What makes up the hypophyseal portal system and what is it?

Answer 66

The primary and secondary capillary plexuses and the intervening hypophyseal portal veins make up the hypophyseal portal system. Via this portal system, releasing and inhibiting hormones secreted by neurons in the ventral hypothalamus circulate to the adenohypophysis, where they regulate secretion of its hormones . All these hypothalamic regulatory hormones are amino acid based, but they vary in size from a single amine to peptides and proteins.

Question 67

What is the "master endocrine gland?"

Answer 67

Hypothalamus

Question 68

Growth hormones are produced by what and stimulate what?

Answer 68

Growth hormone is produced by cells called somatotropin of the anterior Lobe. Although GH stimulates most body cells to increase in sized and divide, it's major targets are the bones and skeletal muscles

Question 69

Which hormone is more important in general as a regulatory factor and why?

Answer 69

The hypothalamic are more important than the inhibiting hormones because only very little hormone is stored by secretory cells of the anterior lobe.

Question 70

What pituitary hormones are tropics or tropic hormones (hormones that regulate the secretory action of other endocrine glands).

Answer 70

Thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, and luteinizing hormone. Except for growth hormones all affect their target cells via a cyclic AMP second-messenger system.

Question 71

What promotes protein synthesis and encourages the use of fats for fuel, conserving glucose?

Answer 71

Growth hormone (GH)

Question 72

Growth hormone is mediated by insulin-like growth factors (IGFs) also known As somatomedins. What are somatomedins?

Answer 72

A family of growth-promoting proteins produced by the liver, skeletal muscle, bone, and other tissues.

Question 73

Secretion of GH is regulated by chiefly two hypothalamic hormones with antagonistic effects. What are they?

Answer 73

* Growth hormone-releasing hormone (GHRH)- stimulates GH release * growth inhibiting hormone (GHIH)- also called somatostatin, inhibits it.

Question 74

Thyroid stimulating hormone (TSH). Or thyrotropin

Answer 74

Tropic hormone that stimulates normal development and secretory activity of the thyroid gland. Triggered by the hypothalamic peptide thyrotropin-releasing hormone (TRH).

Question 75

Adrenocorticotropic hormone (ACTH)

Answer 75

Stimulates the adrenal cortex to release corticosteroid hormones, most importantly glucocorticoids that help the body resist stressors.

Question 76

Gonadotropins

Answer 76

Regulate the function of the gonads (ovaries and testes)

Question 77

Prolactin (PRL)

Answer 77

In women it stimulates milk production, in men it is unknown

Question 78

PRL release is stimulated by what?

Answer 78

It is stimulated by estrogen

Question 79

What does anti diuretic hormone (ADH) influence? What does oxytocin influence?

Answer 79

ADH influences body water balance and oxytocin stimulates the contraction of smooth muscle, particularly that of the uterus and breasts.