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Question 1

how does the endocrine system function?

Answer 1

• through the secretion of hormones that travel through the blood stream
• endocrine galnds are ductless in that they produce/secrete glands into the interstitial space where they are taken up by lymphatic capillaries and transported to the blood stream

Question 2

anterior pituitary gland secretions

Answer 2

ACTH, TSH, GH, PRL, FSH, LH, MSH

Question 3

posterior pituitary gland secretions

Answer 3

oxytocin and ADH

Question 4

pineal gland secretions

Answer 4

melatonin

Question 5

parathyroid glands secretions

Answer 5

PTH

Question 6

thyroid gland secretions

Answer 6

T3, T4 and calcitonin

Question 7

medulla of adrenal gland secretions

Answer 7

E and NE

Question 8

cortex of adrenal gland secretions

Answer 8

cortisol, corticosterone, cortisone, aldosterone, andgrogens

Question 9

male gonad secretions

Answer 9

androgens (mainly testosterone) and inhibin

Question 10

female gonad secretions

Answer 10

estogens (mainly estradiol), progestins and inhibin

Question 11

pancreatic islet secretions

Answer 11

insulin, somatostatin and glucagon

Question 12

hypothalmus secretions

Answer 12

ADH, oxytocin and regulatory hormones

Question 13

accessory endocrine organs include

Answer 13

• the stomach, smi, heart and kindeys

- have some endocrine tissue but its not their major function

Question 14

types of hormones

Answer 14

• amino acid derivatives (most common):
  - catecholamines
  - peptide hormones
• steroid hormones (synthesized from cholesterol)
  - by gonads/adrenal glands

Question 15

basic mechanism for hormones initiating a respone

Answer 15

• binding of the hormone to a receptor causes biochemical events that changes tha pattern of enzymatic activity in the cell
• aa hormones cant pass through the membrane so theu bind to a receptor of the membrane and activate second messanger pathways
• most common 2nd messanger = cAMP
• steroids can diffuse through the membrane and bind to a cytoplasmic receptor, translocates to the nucleus and activates/inactivates genes altering rna transcription rates - altering protein synthesis - altering metabolic activity

Question 16

hypothalamic pathway to adrenal glands

Answer 16

• controls sympathetic output of adrenal galnds
• through preganglionic motor nerve fibres
• output of adrenal galnds (E & NE) enters blood stream immediately and circulates

Question 17

hypothalamus is like the:

Answer 17

king pin of the endocrine system - controls all secretions

Question 18

hypothalamus and posterior pituitary

Answer 18

-hypothalamus nerve cells produce oxytocin and ADH
-travel to posterior pituitary by hypothalamohypophyseal tract
-hormones are then stored in the posterior pituitary until they are needed - then release
(no actual hormone production in posterior pit)

Question 19

hypothalamus and anterior pituitary

Answer 19

• release of anterior pituitary hormones is under the control of other organs
• hypothalamus stimulates ant pit to produce and secrete hormones into the blood stream through the hypothalamic hypophyseal portal system

Question 20

both the pineal and the pituitary gland are a part of the

Answer 20

diancephalon

Question 21

pituitary gland gross anatomy

Answer 21

• size and shape of a pea - on the end of a stalk
• found seated in sphenoid bone
• two lobes - the posterior and the anterior
• post pit is connected to the hypothalamus by the infundibulum (contains hypo.. tract)
• anterior pituitary is connected to the optic chiasm

Question 22

what does oxytocin do

Answer 22

• stimulates myometrial contractions - helps push fetus out

- allows release of milk from mamary glands

Question 23

what does ADH do

Answer 23

decreases water loss from kidneys - promotes reuptake of water

Question 24

posterior pituitary anatomy

Answer 24

• made from neural tissue
• pituocytes
• also called pars nervosa

Question 25

anterior pituitary anatomy

Answer 25

- made from glandular tissue - has three regions: - pars distalis (TSH, ACTH, FSH, LH, PRL, GH) - pars intermedia (MSH) - pars tuberalis - wraps around infindibulum

Question 26

space between two lobes of pituitary gland develops why?

Answer 26

because of how the pituitary gland grows: -post pit grows down from brain -ant pit grows up from oval tissue (grow towards each other)

Question 27

paraventricular nucleus of hypothalamus

Answer 27

-neurosecretory cells producing and releasing inhibiting hormones

Question 28

supraoptic nucleus of hypothalamus

Answer 28

-neurosecratory cells producing ADH and oxytocin

Question 29

GH actions

Answer 29

- acts on epiphyseal plate of bone for bone growth - acts on regulating muscle mass - acts on adipose tissue to release free fatty acids for growth

Question 30

PRL actions

Answer 30

-acts on mamary glands to induce milk secretion

Question 31

ACTH actions

Answer 31

-acts on adrenal cortex - to secrete cortisol

Question 32

TSH actions

Answer 32

-acts on the thyroid - secretion of t3/t4

Question 33

FSH actions

Answer 33

- follicular development and estrogen secretion | - spermatogenesis

Question 34

LH actions

Answer 34

- ovulation and progesterone secretions | - androgen secretion from testes

Question 35

hypothalamic hypophyseal portal system

Answer 35

- blood comes from branches of internal carotid arteries - primary capillary plexus = superior hypophyseal artery - fenstrated capillaries, supplies infindibulum - secondary capillary plexus = hypophyseal veins - drains blood - portal veins connect primary and secondary plexi - inferior hypophyseal artery supplies posterior lobe and is drained by hypophyseal veins