Chapter 18 - The Endocrine System

Question 1

Endocrine: Secrets hormones into …

Answer 1

interstitial fluid —> blood

Question 2

Exocrine: Secrets products into …

Answer 2

ducts that carry product into body cavity

Question 3

Upregualtion

Answer 3

target cell receptors INCREASE, making the target cell MORE sensitive to a hormone
ex. Increased oxytocin levels during labor

Question 4

Downregulation

Answer 4

target cell receptors DECREASE, making the target cell LESS sensitive to a hormone
ex. insulin receptors downregualte in type II diabetes

Question 5

Local Hormone types

Answer 5

Autocrine and Paracrine

Question 6

Circulating Hormone types

Answer 6

Neurocrine and Endocrine

Question 7

Paracrine acts on…

Answer 7

Nearby target cells

Question 8

Autocrine acts on…

Answer 8

Its own cell

Question 9

Neurocrine

Answer 9

Hormone released by “neurosecretory” cell

ex. antidiuretic hormone (hypothalamus and posterior pituitary)

Question 10

Endocrine

Answer 10

Hormone released by secretory cells

ex. adrenocorocpropin (most endocrine organs)

Question 11

Lipid-Soluable hormones

Answer 11

Steroid hormones (Cortisol), Thyroid hormones (T3, T4), Nitric Oxide

Question 12

Water-Soluable hormones

Answer 12

Amine hormones (epinephrine), Peptide and Protein Hormones (Anti-diuretic hormone), Eicosanoids (prostaglandin)

Question 13

Hydophobic vs Hydophillic messengers …

Answer 13

Hydophobic are secreted by diffusion and are bound to carrier proteins in blood stream; Hydrophillic are secreted by exocytosis and are dissolved in blood stream

Question 14

Lipid-Soluable hormones…

Answer 14

1) Hormone binds to receptor 2) hormone- receptro complex binds to DNA 3) Hormone-receptor complex acts as a transcription factor 4) up/down regualtes genes 5) change in gene expression alters cell structure and function

Question 15

Water-Soluable hormones

Answer 15

1) Hormone (first messenger) binds to membrane bound receptor 2) Hormone binding activates second messenger inside the cell 3) Second messenger activates protein kinase 4) Protein kinases phosphorylate cellular proteins
5) Phosphorylated proteins cause reactions which produce physiological responses

Question 16

Action of Hormone

Answer 16

Antagonistic effect (is opposed by another hormone) 
Permissive Effect (Requires simultaneous or recent exposure to second hormone)
Synergistic effect (is greater or more extensive when acting with a second hormone)

Question 17

The hypothalamus controles…

Answer 17

Autonomic nervous system, Hormone production, body temp, emotion/behaviour, Eating/Drinking, Circadian Rhythm and Consciousness

Question 18

Anterior Pituitary secrets which hormones…

Answer 18

Human growth hormone

Question 19

hGH is controlled by which hormones? What is its Function?

Answer 19

Growth hormone - releasing hormone (GHRH)
Growth hormone - inhibiting hormone (GHIH)
Human growth hormone Elicits secretion and release of insulin-like growth factors (IGF)

Question 20

Insulin like growth factors (IGF) are released by…

Answer 20

Skeletal muscles, bone, cartilage, live, other tissues

function: growth and maintenance , glucose metabolism (negative feedback)

Question 21

Thyroid- stimulating hormone (TSH) - Anterior pituitary

Answer 21

Releasing hormone: Thrytropin-releasing hormone (TRH)
Inhibiting hormone:
Growth hormone-inhibiting hormone (GHIH)
Function: Stimulates synthesis of thyroid hormones (T3 & T4)

Question 22

Adrenocorticotropic hormone (AC) - Anterior Pituitary

Answer 22

released by: corticotropin-releasing hormone (CRH)

Function: Stimulates secretion of glucocorticoids and andorgens by adrenal cortex

Question 23

Melanocyte-stimulating hormone (MSH) - Anterior pituitary

Answer 23

Released by: corticotropin-releasing hormone (CRH)
Inhibited by: Prolactin - inhibiting hormone (PIH) aka dopamine
Function: Influences brain activity, darkens skin

Question 24

Antidiuretic hormone (ADH)
- Posterior Pituitary

Answer 24

Function: Decreases urine production, Increase water retention, increase blood pressure

Question 25

Synthesis and secretion of T3 and T4

Answer 25

1. Thyroid follicular cells trap iodide ions 2. Thyroid follicular cells synthesis TGB (Thyroglobulin) 3. TGB released into the Lumen of the follicular cell 4. Iodide is oxidized to iodine 5. Iodine + TGB on tyrosine protein 6. This collision forms, Colloid, stick material 7. T1 and T2 are formed 8. Coupling of T1 and T2 forms T3 and T4 9. diffuse into blood 10. Traveling in blood bound to thyroxinebinding globulin (TBG)

Question 26

Calcitonin

Answer 26

jh

Question 27

Parathyroid hormone (PTH)

Answer 27

lkj

Question 28

Calcitriol

Answer 28

lkj

Question 29

Synthesis of mineralocorticoid - aldosterone

Answer 29

lkj

Question 30

Glucocorticoids

Answer 30

zona fasciculata 1. Cortisol 2. Corticosterone 3. Cortisone

Question 31

Androgens

Answer 31

Zona recticularis 1. Dehydroepiandrosteorne (DHEA) - precursor to sex hormones

Question 32

Mineralcorticoid (mainly aldosterone)

Answer 32

Zona glomularis

Question 33

Adrenal medulla makes...

Answer 33

Epinephrine (80%) | norepinephrine (20%)

Question 34

Pineal Gland

Answer 34

Composed of Neurolia and pinealocytes - secretes melatonin - controlled by suprachiasmatic nucleus - function: sets biological clock

Question 35

stress response

Answer 35

1. stimulus 2. sympathetic 3. short response (fight or flight) 4. resistance reaction (CRH, GHRH, TRH are released to help body continue fighting the stressor) 5. exhaustion

Question 36

Fight or Flight Response

Answer 36

Increases sympathetic nervous system activity to... 1. Effector organ (heart, blood vessels) 2. Adrenal Medulla (hormone release -- lasts 5-10 times longer than nueral stimulation)

Question 37

Resistance reaction

Answer 37

Hormone release by hypothalamus - longer Lasting response | - Cortisol, Aldosterone, T3, T4, Adipocytes

Question 38

Exhaustion

Answer 38

Depletion of resources - muscles wasting - immune suppression - beta cell failure

Question 39

Aging Endocrine system | Reductions

Answer 39

``` hGH -- muscles atrophy T3, T4 -- Decreased metabolic rate, increase body fat Calcitonin -- Osteoporosis Corisol, Aldosterone -- decrease Insulin release -- decreases ```

Question 40

Aging Endocrine System (Increases)

Answer 40

PTH -- Osteoporosis

Question 41

Thyroid is regulated by .. | and releases...

Answer 41

TSH and blood calcium levels | and releases T3, T4 and calcitonin

Question 42

Parathyroid is regulated by... and releases...

Answer 42

Regulated by blood calcium levels | and releases PTH, triggers kidney to release calcitriol

Question 43

calcitrol vs calcitonin

Answer 43

Calcitrol increases blood calcium and is an active form of Vitamin D, Calcitonin decreases blood calcium levels