Ch. 18 Endocrine system

Helpfulness: 0
Set Details Share
created 5 years ago by Tassimcc
789 views
updated 5 years ago by Tassimcc
show moreless
Page to share:
Embed this setcancel
COPY
code changes based on your size selection
Size:
X
Show:
1

Endocrine glands

Secrete hormones directly into the bloodstream

2

Hormone

molecule that regulates cellular activities

3

Endocrine glands & Hormone

Acts together with nervous system

4

Hormone receptors

usually proteins, Bind ONLY to their specific hormone!, Constantly synthesized & degraded

5

Up-regulation

makes target cells MORE SENSITIVE to a hormone

6

Down-regulation

makes target cells LESS SENSITIVE to a hormone

7

Importance of receptor specificity

Hormone-receptor interaction is VITAL to a hormone’s function! It binds to specific receptors on target cells

8

Lipid-soluble

bound to transport protein includes steroids hormone, thyroid hormone, gases

9

Water- soluble

circulate in blood plasma includes proteins & peptides, amines, Eicosanoids

10

Lipid-soluble hormone

bind to receptors INSIDE cells

11

Water- soluble hormone

bind to receptors ON CELL MEMBRANE

12

role of nucleus

Hormone binding to receptors in cells (happen in nucleus)

13

gene expression

Activated receptor-hormone complex alter gene expression and new protein are made

14

Mechanism of lipid-soluble

results changes in cells’ activities

15

interactions of G proteins

activates Adenylate cyclase

16

adenylate cyclase

converts ATP to cAMP (2nd messenger)

17

cAMP

2nd messenger

18

role of phosphodiesterase

inactivates (breakdown) cAMP

19

importance of protein phosphorylation

results in various biological reaction!

20

hormone

1st messenger

21

3 Factors that influence target cell sensitivity to a hormone

Hormone concentration in blood, # of receptors present, other hormone influences

22

3 ways hormone secretion is controlled

Nerve signals, Blood chemistry, Other hormones

23

Pituitary gland (Hypophysis)

attaches to hypothalamus by a stalk, sits in sella turcica, contains 2 main lobes: ANTERIOR & POSTERIOR *functionally separate

24

General role of hypothalamus

 special brain region (below thalamus)
 receives many sensory inputs
 synthesizes many hormones
 exerts much control over pituitary gland

25

function of releasing hormones

Hypothalamic hormone stimulate secretion of anterior pituitary hormone

26

function of inhibiting hormones

Hypothalamic hormone prevent secretion of anterior pituitary hormones

27

Role of portal system

Receives hypothalamic hormones through a PORTAL SYSTEM, These hormones reach the anterior pituitary rapidly, Anterior pituitary hormones then travel to target tissues

28

7 major hormones of the ANTERIOR LOBE

hGH, TSH, FSH, LH, PRL, ACTH, MSH

29

effects of hGH

Protein synthesis, Cell growth & repair, Lipolysis, increasing blood glucose, Target cells are in many tissues

30

Target tissues of: TSH

secretion of thyroid hormone by the thyroid gland

31

Target tissues of: FSH & LH

ovaries initiate development of oocytes & ovulation; testes initiate development of spermatozoa & testosterone production

32

Target tissues of: PRL

stimulate breast growth, the mammary glands

33

Target tissues of: ACTH

from the adrenal cortex; mineralocorticoid, glucocorticoid, & androgen hormones

34

2 main hormones of the POSTERIOR LOBE

oxytocin & ADH (Antidiuretic Hormone)

35

Target tissues of: oxytocin

smooth muscle in the uterus and Mammary glands

36

Target tissues of: ADH

ducts in the kidney and sweat glands to minimize water loss and directly causes arterioles to constrict which increasing blood pressure

37

Follicular cells

secrete T3 and T4

38

Parafollicular cells

secrete calcitonin (CT)

39

IODINE

Hormone synthesis requires_____ in Thyroid

40

thyroid follicles

Synthesis of Thyroid hormone occurs in _______

41

Effects of T3 & T4

Increases BMR (and thus, core temp.), Growth (protein synthesis), Lipolysis, Enhancement of adrenaline

42

What hormone stimulates thyroid hormone secretion?

TSH and Ca2+

43

Effect of calcitonin (CT)

Decreases blood calcium

44

What stimulates CT secretion?

parafollicular (C-cells) of the thyroid gland

45

calcitonin

An increase in blood calcium will stimulate the C-cells of the thyroid to secrete _____

46

Increased calcitonin

causes a decrease in blood calcium

47

Adrenal cortex; 3 main hormone

Mineralocorticoids ,Glucocorticoids, Androgens
*these are steroid hormone*

48

Functions of ALDOSTERONE

Electrolyte (NA+, K+) regulation, Blood pressure, blood volume regulation
**secretion stimulated by the “Renin – angiotensin system”

49

what special pathway stimulates ALDOSTERONE secretion?

angiotensin II

50

Aldosterone

main hormone of Mineralocorticoids

51

Effects of CORTISOL

Gluconeogenesis (breakdown protein & fats to form glucose), hyperglycemia, Lipolysis, protein catabolism, Anti-inflammatory J , Stress response, Immunosuppression

52

what stimulates CORTISOL secretion?

ACTH

53

Cortisol

major hormone of glucocorticoid

54

What stimulates secretion of ANDROGENS?

ACTH

55

what is the main hormone of Adrenal medulla

EPINEPHRINE

56

Effects of EPINEPHRINE

Intensifies “fight-or-flight” responses

57

“fight-or-flight” functions

Increases HR, BP & blood glucose , Decreases blood flow to GI, Pupil dilation, Broncho-dilation

58

What stimulates secretion of EPI/NE?

ACh

59

What are the common cell in the pancreas

Acini

60

Where is the pancreas hormone secretion?

pancreatic islets

61

Alpha cells

secrete GLUCAGON

62

Beta cells

secrete INSULIN*

63

F cells

secrete PANCREATIC POLYPEPTIDE

64

Delta cells

secrete SOMATOSTATIN

65

Function of GLUCAGON

increase blood glucose, (done by hepatocytes)

66

what stimulates GLUCAGON secretion?

Decreases blood glucose (hypoglycemia), Increases sympathetic activity (exercise)

67

Function of INSULIN

decrease blood glucose

68

what stimulates INSULIN secretion?

Increases blood glucose (hyperglycemia), Various other hormone

69

role of “GluT” transporters

Glucose enters cells via facilitated diffusion

70

Type I diabetes mellitus

beta cell destruction causes very low secretion of insulin; Requires insulin injections, Diabetic ketoacidosis can occur

71

Type II diabetes mellitus

glucose transporter abnormalities (often cause insulin resistance); linked to obesity, Managed by changing diet, meds, etc.

72

Effect of PTH

increases blood calcium (secretion influenced by blood Ca2+

73

what stimulates PTH secretion?

Chief cells

74

What happens when Ca2+ level changes in CT secretion?

Increases blood calcium

75

What happens when Ca2+ level changes in PTH secretion

Decreases blood calcium

76

Ovaries major hormones

ESTROGEN & PROGESTERONE

77

what stimulates Ovaries & testes hormones secretion?

FSH & LH

78

testes major hormones

TESTOSTERONE

79

Pineal gland

Endocrine gland in the brain, Secretes MELATONIN (MT)

80

MELATONIN (MT)secretion

increase in darkness

81

Functions of melatonin (MT)

Regulation of body clock, Potent antioxidant

82

Role of thymosins

Promotes T cells maturation (immunity)

83

Thymus

Secrets THYMOSINS, Behind sternum between lungs (in mediastinum)

84

Effects of aging

Decreases in hGH, T3 & T4, adrenal cortex hormones, estrogen & testosterone secretion; Increases PTH secretion; Atrophy (weaken) of thymus & ovaries

85

Stressor

anything that generates a stress response (physical, emotional, etc.)

86

hypothalamus

Stress response control by _____

87

Three stages of stress responses

“fight-or-flight”, Resistance, Exhaustion

88

“fight-or-flight”—physiologic effects

short-lived

89

resistance — anterior pituitary hormones involved

ACTH, GH, TSH

90

exhaustion — main characteristics

Depleted energy, Immunosuppression , GI ulcers