Endocrine System Flashcards Preview

Anatomy and Physiology > Endocrine System > Flashcards

Flashcards in Endocrine System Deck (57):
1

Describe the overall function of the endocrine system

Reproduction, growth and development, internal homeostasis, helps to cope with environmental changes

2

Contrast endocrine and exocrine glands

-exocrine release content into ducts or skin surface Ex salivary
-endocrine release horemone into blood stream

3

Define hormone and target cell.

-Hormone is made by an endocrine gland & is a chemical messenger traveling in the bloodstream.
-The target cell responds to the hormone because it has matching receptors for the hormone

4

Describe the structure and transport mechanism of hormones

-organic, amino acid (some lipid-reproduction)
-transported in the bloodstream; usually they are attached to some carrier protein making them physically larger so that they are not urinated out.

5

Explain how a hormone affects the activity of target cells

-It can go to the nucleus and act upon the genes
-or it can stimulate and intermediate compound such as cAMP, which acts as a second messenger and stimulates or inhibits a process or metabolic pathway in the cell. (assisting in chain reaction)

6

Define hypophysis

-Pituitary gland

7

Identify the location of the pituitary gland

- in Sella Turcica of sphenoid bone

8

Describe the 2 lobes of the pituitary gland, include which hormones are released by each lobe and their function

Anterior pituitary:
-FSH causes sperm production in male and follicle maturation in female
-LH=ICSH causes interstitial cells of testes to make testosterone in male and causes ovulation in female
-TSH stimulates the thyroid gland to make hormone
-ACTH stimulates the adrenal cortex to make hormone
-GH causes growth
-Prolactin causes milk production in females
-MSH causes skin pigment (melanin) to be produced.

(endorphins not hormone, but released here)

Neurohypophysis- posterior lobe (doesn't make hormones, stores and releases hormones from hypothalamus
-ADH-antidiuretic water reabsorption (from urine to blood) in kidney
-Oxytocin-contractions milk let down

9

Define Endorphines

-peptides made by adenohypophysis in addition to the hormones that has
-blocks neurotransmitter
-not a hormone but is really a neuromodulator
-Morphine like compound made by anterior pituitary gland

10

Describe the controls of the pituitary gland

-.Hypothalamus makes stimulatory hormones called releasing hormones and inhibitory hormones; Negative feedback

11

Explain why the posterior pituitary is not a TRUE endocrine gland

It doesn't make ADH and Oxytocin. They are made by hypothalamus but stored and released by posterior pituitary.

12

Describe the location and histology of the thyroid gland

-inferior to larynx
-follicles filled with thyroid hormone (colloid), and the surrounding follicle cells make the hormone.
-The interstitial cells are called parafollicular cells and make calcitonin (controls calcium levels)

13

Name and describe the formation and function of thyroid hormones

-Made from an amino acid called tyrosine.
-Three iodine molecules in T3 and four in T4.

14

Describe how thyroid hormones are transported in the bloodstream

-the thyroid hormone is transported on plasma globulin TBG

15

Describe the controls over thyroid hormone synthesis and release

-synthesized by iodine (only place in body) combining with Tyrosine to make T4 (90%) and T3 (10%)
- Regulates metabolic rate
-Negative feedback, TSH from anterior pituitary and Thyroid releasing hormone from hypothalamus.

16

Name the gland and cell that make calcitonin

-Parafollicular cells of the thyroid- C Cells

17

Describe the function and control of Calcitonin

-Decreases Calcium and phosphate in blood stream
-Important because Calcium controls muscle contraction, too much can cause heart attack

18

Describe the location of the parathyroid gland and the function of its hormone and the controls of its release

-Embedded in the thyroid gland. (4 of them)
-It makes Parathyroid hormone which increases blood calcium levels.
-Obviously, blood calcium levels determine whether PTH or Calcitonin should be released.

19

Describe the location and the 2 portions of the adrenal gland

-Superior to Kidney
-Adrenal Medulla (epinephrine and norepinephrine)
-Adrenal Cortex

20

Name the three layers of the adrenal cortex. Name and describe the effects of the hormones made by each layer. Describe the controls of their release

-Outer is the zona glomerulosa
-aldosterone is made which causes sodium reabsorption in the kidneys (sodium goes from urine back to blood, and water passively follows)
-Zona fasciculata is middle layer
- making glucocorticoids that help one deal with long term stress by conserving energy for later.
-It is also anti-inflammatory.
-Inner zone is zona reticularis
-making sex hormones to be discussed under reproduction.

-Of course ACTH from the ant. pituitary stimulates the release of these hormones. Also, low blood sodium would stimulate release of aldosterone. If your blood pressure is low, the kidneys release renin. Renin is an enzyme that converts angiotensinogen to angiotensin. These will be discussed under cardiovascular system. However, angiotensin can cause the adrenal cortex to release aldosterone. Since aldosterone causes more salt to be in the bloodstream, and water passively follows, it will help to restore the low blood pressure to a more normal value.

21

Define islets of langerhans, pancreatic islets, and chromaffin cells

-Islets of Langerhans = pancreatic islets and are the endocrine cells of the pancreas.
-The chromaffin cells are the endocrine cells of the adrenal medulla.

22

Name the organ that has both exocrine and endocrine functions

-Pancreas

23

Describe the location and structure of the pancreas

- Behind the stomach, along the duodenum

24

Name the cells that make insulin, glucagon, and somatostatin, describe their effects.

-Beta (islet) cells make Insulin- Lowers blood glucose by allowing it to go into cells
-Alpha cells make Glucagon- Raises blood glucose by bringing it out of storage
-Delta cells make Somatostatin- Inhibits GH release

25

Describe the controls of insulin and glucagon release

-High blood glucose leads to insulin release
-Low blood glucose leads to glucagon release.
-They are released in urine
- glucose level is 0 at homeostasis.
-GI hormones- meal time and in between meals

26

Name the male and female gonads and briefly describe their endocrine roles.

-Testis- androgen
-Ovaries- Estrogen and progestrone

27

Describe the location and function of the pineal gland

-roof of third ventricle.
-Makes melatonin (color pigment) which depresses reproductive activity

28

Name the gland that is replaced by connective tissue and fat in adults. Briefly describe its location and function.

-Thymus. superior to cerebellum (calcifies with age)
-It has a lymphatic role, in that T lymphocytes are made and "trained" here.
-The endocrine role is that it releases thymic hormone to stimulate these T cells. (immunity)

29

Describe the structure and function of prostaglandins

-Unique group of hormones because made from fatty acids
-promote pain (how tylenol works)
-They are unique in that they tend to act locally. -For example, a prostaglandin released by the uterus into the bloodstream has target cells in the uterus and acts upon the uterus.

30

name the two hormones made by the adrenal medulla and describe their functions and the controls of their releases.

-Epinephrine & Norepinephrine are released under fight of flight situations.
-They exaggerate the fight or flight response. Mostly, epinephrine is released.

31

FSH

-gonadotropins (pituitary)
-Follicle stimulation hormone- stimulates follicle development in ovaries, stimulates sperm production and maturation in male

32

LH/ ICSH

-gonadotropins (Pituitary)
-Luteinizing hormone results in ovulation in female, Interstitial cell stimulating hormone results in testosterone production

33

TSH

-Pituitary
Thyroid stimulating hormone

34

ACTH

-Pituitary
-Adrenocorticotropic hormone (above kidney cortext stiumulating)

35

GH

-Pituitary
-Growth hormone

36

Prolactin

-initiates and maintains milk production in female
-pituitary

37

MSH

-Pituitary
-Melanocyte stimulates skin pigment

38

ADH

-Posterior Pituitary (hypothalamus)
-water reabsorbtion from kidney to bloodstream

39

Oxytocin

--Posterior Pituitary (hypothalamus)
-Quick birth, uterine contractions for child birth

40

t4 and t3

-thyroid
-thyroxine+ iodine

41

TBG

Thyroid hormones are carried in the plasma bound to this globulin

42

TSH and TRH

Thyroid
Plays role in reproduction
-negative feedback loop

43

-Calcitonin

-c cells,
-decreases calcium and phosporase

44

PTH

Parathyroid function
-increases ca and decreases p

45

Epinephrine and norepinephrine

- Adrenal gland
in the medulla
glucose (SNS, endocrine)

46

Aldosterone

-Adarenal cortex
-Na reasorbed

47

Renin

Kidney enzyme

48

Angiotensinogen

-made by liver

49

Glucocorticoids

-group of hormones that deal with long term stresses
- anti inflammatory
-adrenal cortex- zona fasciculata

50

Insulin

-pancreas
-lowers blood glucose

51

Glucagon

-Pancreas
-raises blood glucose

52

Somatostatin

-Pancreas
-inhibits growth hormone

53

Androgen

testis

54

Estrogen and Progesterone

Overies

55

Melatonin

-decreases reproductive activity
-penial gland

56

Thymic hormone

help develop t cells
-thylamus

57

Prostigladins

Unique hormones bc made fatty acids
-promote pain (why tylenol works)