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Flashcards in Chap 6 Deck (81):
1

What is a hormone?

Is the mediator molecule released in the whole body from endocrine glands to specific receptors

2

What do exocrine glands do?

Secrete their products into ducts carrying secretions into body cavities (e.g., digestive enzymes)

3

What do endocrine glands do?

Release hormones into the interstitial fluid. Hormones then diffuse into bloodstream (e.g., pituitary gland

4

List some exocrine glands

Salivary glands that secrete saliva into the mouth
Bile-producing glands of the liver
Prostate gland
The portion of the pancreas that secretes pancreatic fluid into the duodenum
Gastric glands
Sweat glands

5

What are primary endocrine glands in CNS

Hypothalamus
Pituitary gland
Pineal gland

6

Primary Endocrine glands outside of CNS

Thyroid gland
Parathyroid gland
Thymus
Adrenal gland
Pancreas
Gonads (ovaries and testes)

7

Secondary endocrine glands

Kidneys
Stomach
Liver
Small intestine
Skin
Heart

8

What are the targets of hormones

glycoprotein receptors

9

What two mechanisms regulate the number of cell receptors?

Down-regulation (suppression)
Up-regulation (sensitivity increase)

10

How do circulating hormones move?

use bloodstream as a vehicle to reach their cell targets

11

What do local hormones do? Give two examples.

act on their surrounding cells or on themselves
Paracrines, act on nearby cell. Autocrine, act on self

12

How do water soluble hormones circulate

circulate in a free form in blood

13

Lipid soluble hormones circulate how?

need a vehicle (transport proteins) to reach the target cells

14

What three functions do transport proteins have?

Make LSH temporally WSH
Delay the filtering mechanism
Provide a LSH reserve in bloodstream

15

What are the two classes of hormones?

Lipid soluble and water soluble

16

Three types of lipid soluble hormones and how they are derived.

Steroid hormones derived from cholesterol
Thyroid hormones synthesized from iodine and AA tyrosine
Nitric Oxide (NO) catalyzed by NO-synthase

17

LSH mechanisms of action (4)

A free LSH diffuses from the blood through the cell
LSH binds and activates the receptor within cytosol or nucleus which in turn will alter gene expression
From this, new proteins are built
These new proteins will trigger an increase or a decrease in LSH level into the cell

18

WSH mechanisms of action (6)

WSH diffuses from blood to external cell layer and binds with receptor
Adenylyl cyclase converts ATP to cAMP
cAMP serves as second messager to activate protein kinase
Protein kinase phosphorylates other enzymes
This produces million of biochemical reactions
After brief period, cAMP is desactivated

19

The responsiveness of a target cell to a specific hormone depends on

Hormone concentration
Number of cell receptors
Influence of antagonist hormones

20

Hormone secretion is regulated by

Signals from Nervous System
Chemical changes in blood
Influence of antagonist hormones

21

Hypothalamus is interface between what?

Nervous system and endocrine system

22

Hypothalamus Influenced by what?

Pain, stress, emotion

23

Hypothalamus controls what?

ANS, body temperature, thirst, hunger, sex,

24

Hypothalamus synthesizes how many hormones?

9

25

What does anterior pituitary gland do

secretes hormones regulating a wide range of bodily activities

26

What does posterior pituitary gland do?

contains axons and axon terminals (10 000 neurons) related to the hypothalamus

27

Neurosecretary cells from hypothalamus have 5 what and 2 what

5 releasing hormones that stimulate secretion and two releasing hormones that decrease secretion

28

Human growth hormone released from? Main function? What are the target cells? Released where?

Anterior pituitary. stimulate synthesis and secretion of Insulin growth factors. Target cells are liver, skeltal muscle cartlidge and bone. released in blood stream or acts locally

29

What are some IGF functions?

Increase uptake of AA by cells,decrease AA breakdown, use AA as a substrate for ATP, enhance lypolysis, decrease glucose uptake,

30

IGF and hGF stimulate release of?

Liver glucose

31

What do somatotrophs do?

Release hGH every few hours mainly during sleep

32

What does Growth hormone-releasing hormone do

Promotes secretions of hGH

33

What does Growth hormone-inhibiting hormone do

Supresses secretions of hGH

34

what is major regulator of GHRH and GHIH?

blood glucose level

35

High blood glucose stim release of? Low blood glucose?

GHIH, GHRH

36

What does TRH do?

Controls TSH release from hypothalamus

37

What does TSH do

Stimulates T3 and T4 both in thyroid gland

38

What do T3 and T4 hormones do?

Inhibit TRH(feedback loop)

39

How is foccile-stimulating hormone strimulated?

When hypothalamus releases GnRH

40

FSH stimulates what

Follicular cells to secrete estrogen, sperm producton and development of several ovarian follicles

41

GnRH and FSH are inhibited by

estrogens and testosterones

42

H is stimulated by ?

GnRH

43

LH triggers what? (3)

ovulation, estrogens, and stimulation of interstitial cells in the testes to secrete testosterones

44

what do estrogens and progesterone do?

prepare for fertilizing mechanisms and milk secretion

45

What does prolactin hormone do?

Initiates and maintains lactation

46

Coticotroph cells secrete what?

ACTH

47

what does ACTH do

Controls secretion of cortisol and glucocorticoids

48

Increased released ACTH how >

stress

49

posterior pituitary also called

neurohypophysis

50

Posterior Pit. doesnt do what? What does it do? Relies on what?

Doesn't synthesize hormones, stores and releases oxytocin and ADH. Hypothalamus

51

Oxytocin serves mainly as? Stimulates what? involved in what?

Smooth muscle stimulator. Milk ejection, sexual pleasure.

52

ADH regulates fluid balance by?

Decreasing urine volume, decreasing sweat water loss, increasing blood pressure

53

What regulates ADH secretion

blood osmotic pressure and blood volume

54

Thyroid gland releases what?

T3 and T4 and CT

55

Stores T3 and T4 in small or large quantity?

Large.

56

T3 and T4 formed where, CT formed where?

Follicular, and parafollicular

57

T3 and T4 hormones do what?

Increase BMR
stimulate protein synthesis
Increase glucose and FA uptake for ATP production
Increase lipolysis
Enhance cholesterol excretion
Accelerate body growth
Contribute to CNS development

58

CT in involved in what

regulation of Ca2+ and phosphates

59

CT secretion is controlled by ?

Feedback loop

60

What does the parathyroid gland involve?

Ca2+ regulation and Mg2+ regulation

61

Adrenal gland is subdivided into what?

Adrenal cortex: 80-90% of the gland, and adrenal medulla which is centrally located

62

Adrenal cortex divided into 3 zones

Glomerulosa, fasciculata, and reticularis

63

What does each zone of adrenal cortex do

Glomerulosa- Secretes aldosterone, Fasciculata- secretes cortisol, corticosterone and cortisone(increase prot. breakdown. Reticularis- secretes DHEA(growth and sexual functions)

64

Glucocorticoids and effects

Protein breakdown

Glucose formation

Lipolysis

Resistance to stress

Anti-inflammatory effects

Depression of immune system

65

Adrenal Medulla secrete two hormones

Epinephrine =80% of secreted hormones, norepinephrine=20% of secreted hormones

66

Pancreas endocrine or exocrine functions?

Both

67

Pancreatic cells arranged in clusters called? produce what?

Acini-produce digestive enzymes

68

Four types of hormones that pancreas secretes

Alpha cells, Beta cells, Delta cells, F cells

69

What do alpha cells do?

Secrete glucagon, raise glucose level

70

What do beta cells do?

Secrete insulin, lower glucose

71

What do delta cells do?

Secrete somatostatin, inhibit glucagon and insulin

72

what do F cells do?

Secrete polypeptide, inhibit somatostatin and digestive enzymes

73

What is the most important stimulator of inisulin?is that the only stimulator?

Glucose level. No many others

74

What else will stim release of glucagon?

Sympathetic activity (ANS) and a rise in blood AA parallel with low glucose

75

Ovaries produce what?

Produce estrogens, progesterone, FSH and relaxin

76

What does the pineal gland function as?

Secretes melatonin

77

What does melatonin do?

inhibits reproductive functions in animals

78

General adaptation syndrom caused by what? Results in what?

stressful conditions, Homeostasis disrupton

79

fight or flight response initiated by what ?

Hypothalammus through SNS

80

What does flight or fight response do?

Brings huge amounts of O2 and glucose to brain muscle and heart, inhibits other organ functions

81

What is the resistance reaction?

Allows to continue fighting a stressor long after fight or flight dissapeared