Pituitary Gland

Question 1

The pituitary gland works closely with what?

Answer 1

Hypothalamus

Question 2

Describe the structure of the pituitary gland.

Answer 2

Anterior & posterior portions. There is an intermediate portion that is merely a cluster of cells. It is connected to the brain by a stalk called the “infundibulum.” Housed by sphenoid bone, sits on sella turcica.

Question 3

What is special about this gland during pregnancy?

Answer 3

It becomes 50% larger during pregnancy.

Question 4

What is the role of the intermediate lobe?

Answer 4

Secretes melanin (eyes, hair, skin). MSH (melanin stimulating hormone) is produced here.

Question 5

Which portion of the pituitary gland is implicated in Addison’s?

Answer 5

intermediate lobe

Question 6

The anterior lobe is also called the ___

Answer 6

adenohypophysis

Question 7

Describe the anterior lobe

Answer 7

3/4 larger than the posterior portion. It is made of embryonic tissue from the pharynx. It has no nervous tissue connecting it to the hypothalamus. No neurons. Hypophyseal portal system. Synthesizes 6 hormones.

Question 8

Describe the posterior lobe

Answer 8

Came down from the brain. Does NOT synthesize hormones. Saves hormones and releases them when necessary.

Question 9

The posterior lobe is also called the ___.

Answer 9

Neurohypophysis

Question 10

Name the 6 hormones that are synthesized in the anterior pituitary gland.

Answer 10

FSH (follicle-stimulating hormone), LH (luteinizing hormone), ACTH (adrenocorticotropic hormone), TSH (thyroid stimulating hormone), PRL (prolactin), GH (growth hormone)

Question 11

What does FSH do?

Answer 11

Females: development of egg-containing follicles in ovaries. stimulates follicular cells to secrete estrogen
Males: testes-stimulates sperm production

Question 12

What is the source of control of FSH & LH?

Answer 12

gonadotropin-releasing hormone from the hypothalamus

Question 13

What does LH do?

Answer 13

Female: releases egg cell; stimulates progesterone. (Ovulation & corpus luteum)
Males: stimulates the testes to release testosterone

Question 14

What does ACTH do?

Answer 14

stimulates the release of glucocorticoids from the 2nd layer (fusicularis) of the adrenal cortex

Question 15

What is the source of control of ACTH?

Answer 15

corticotropin-releasing hormone from the hypothalamus

Question 16

What does TSH do?

Answer 16

stimulates the thyroid gland to secrete thyroid hormone (T3 & T4)

Question 17

What is the source of control of TSH?

Answer 17

thyrotropin-releasing hormone from the hypothalamus

Question 18

What does PRL do?

Answer 18

plays a role in pregnancy, has no effect until AFTER a woman give birth. stimulates mammary glands to synthesize milk.
in males: amplifies effect of LH

Question 19

What is the source of control of PRL?

Answer 19

prolactin release-inhibiting hormone (PIH) and stimulated by prolactin-releasing factor (PRF) from the hypothalamus

Question 20

What does GH do?

Answer 20

Makes up majority of anterior pituitary hormones. 1000x more than any others. Stimulates mitosis &stimulates tissues to differentiate ex. puberty, height, etc. Enhances movement of amino acids through membranes

Question 21

Too much GH before epiphyseal plates close is referred to as?

Answer 21

gigantism

Question 22

Too much GH after epiphyseal plates close is referred to as?

Answer 22

acromegaly

Question 23

Too little GH is referred to as?

Answer 23

dwarfism

Question 24

What is the source of control of GH?

Answer 24

inhibitied by somatostatin (SS) and stimulated by growth hormone-releasing hormone (GHRH) from the hypothalamus

Question 25

Which hormones are released from the posterior pituitary gland?

Answer 25

ADH (anti-diuretic hormone) and OT (oxytocin)

Question 26

What’s another name for ADH?

Answer 26

vasopressin

Question 27

What is the purpose of ADH?

Answer 27

Decreases urine formation. Reduces the volume of water the kidneys excrete.

Question 28

Hypertension does what to ADH and blood pressure?

Answer 28

It will inhibit ADH and lower blood pressure.

Question 29

What is the purpose of OT?

Answer 29

Can contract uterine wall. body becomes more sensitive to OT during pregnancy–late pregnancy. responsible for milk ejection. suckling of infant during breastfeeding releases OT. no established function in males: movement of sperm & fluids in reproductive tract.