Ch. 45 Pt. 3-4 (LAST)

animal hormones(thyroid, parathyroid, pancreas hormones, adrenal glands, gonads, pineal)

what are the thyroid hormones?

1) T3 & T4
2) Calcitonin

what do T3 & T4 do?

stimulate & maintain metabolic processes(blood pressure, heart rate, muscle tone, digestion, reproduction)

what does Calcitonin do?

lowers blood calcium levels

How does calcitonin lower blood calcium levels?

1) tells kidneys to uptake less Ca
2) deposits Ca into bones

normal blood calcium level

10mg/ 100 mL

why is most T4 converted into T3?

T3 has greater affinity to hormone receptors

Explain the hormone cascade pathway when Thyroid Hormone levels drop

1) Hypothalamus secretes TRH(thyrotropin-releasing hormone)
2) TRH stimulates anterior pituitary to release TSH
3) TSH stimulates Thyroid gland to make T3 and T4(increase in thyroid hormones)

—-T3 and T4 help maintain normal blood pressure, heart rate, muscle tone, etc

What happens as Thyroid hormone levels return to normal?

Thyroid hormones block TRH(thyrotropin-releasing hormone) and TSH release

(negative feedback)

Parathyroid hormone function? (fyi its released from parathyroid gland)

raises blood calcium levels (antagonistic to calcitonin)

how does the parathyroid hormone increase blood calcium levels?

1) PTH induce osteoblasts to break down bone→releases calcium into blood

2) makes kidneys reabsorb more Ca

3) stimulate conversion of Vitamin D=intestines take in more Ca

what hormones does the Pancreas secrete?

1) insulin

2) glucagon

What secretes insulin & what does insulin do?

β cells secrete insulin

-insulin decreases blood glucose levels

how does insulin decrease blood glucose levels?

1) tell cells to remove glucose from bloodstream

2) makes liver store glucose as glycogen

what secretes glucagon & what does glucagon do?

alpha(a) cells secretes glucagon

-glucagon raises blood glucose levels

how does glucagon raise blood glucose levels?

breaks down glycogen in liver into glucose & that glucose goes into blood =blood glucose back to normal

Islets of Langerhans?

clusters of endocrine cells that regulate the concentration of glucose in the blood

normal blood glucose level?

70-110 mg glucose/ 100 mL blood

difference between Type 1 & Type 2 diabetes (pancreatic endocrine diseases)

Type 1→ immune cells destroy beta cells in pancreas

Type 2→develop insulin resistance=cells don’t respond to insulin

gestational diabetes

when placental hormones block mother’s insulin in her body=hurts her & baby can get too much glucose stored as fat=becomes fat baby

where is the adrenal gland located & what does it consist of?

located on top of kidneys
1)medulla

2)cortex

general function of adrenal glands

helps body respond to stress

the Adrenal Medulla releases what hormones?

1) epinephrine

2) norepinephrine
(these hormones are for short-term stress, flight & fight response)

effects of epinephrine

increases blood glucose & increases breathing rate/metabolic rates

(adrenaline)

effects of norepinephrine

regulates blood pressure by constricting certain blood vessels =increases blood pressure

the Adrenal Cortex release what hormones?

1) glucocorticoids

2) mineralocorticoids

(both are steroid hormones)

-response to LONG-TERM STRESS

effect of glucocorticoids

1) increase blood glucose levels by breaking down proteins & fats→ glucose

2) partial suppression of immune system

effect of mineralocorticoids

1) promote reabsorption of Na” ions/water by kidneys & exertion of K+ ions

2) increase blood volume/pressure

Ovaries release which hormones?

1) Estrogen

2) Progesterone
(some androgens)

effects of Estrogen; where is it also produced in?

1) stimulate uterine lining growth

2) promote growth of female secondary characteristics

-also produced in brain

effects of Progesterone; what’s it also produced by?

promote uterine lining growth

-also produced by placenta

Testes produce which hormones?

Mainly Androgens(i.e Testosterone)

effects of Androgens

1) support sperm formation
2) stimulate development of male characteristics

3) sex drive

Pineal Gland produces which hormone?

Melatonin

effect of melatonin

decreases activity of neurons in suprachiasmatic nucleus(SCN) which functions as biological clock