Biology: Chapter 5: Endocrine System

Question 1

What are Peptide Hormones

Answer 1

Composed of Amino Acids and are derived from larger precursor proteins that are cleaved during post-translational modification

Question 2

How do peptide hormones travel through the blood stream and bind to their respective receptors

Answer 2

Peptide Hormones are water soluble so they travel freely through the blood stream but cannot pass through lipid membrane and bind to receptors extracellularly

Question 3

What happens when a peptide hormone binds to their receptor

Answer 3

They trigger transmission of a secondary messenger which causes a signaling cascade to amplify the signal

Question 4

What is the onset and duration of peptide hormones

Answer 4

Rapid Onset and Short Duration

Question 5

What are Steroid Hormones made from

Answer 5

Derived from cholesterol

Question 6

How to Steroid Hormones travel through the blood stream and bind to their respective receptor

Answer 6

Steroid hormones are not water soluble and therefore require a carrier through the bloodstream; They can pass through the lipid membrane and bind intracellularly

Question 7

What is the mechanism of action of steroid hormones

Answer 7

Once bound they cause a conformational change in the receptor; the hormone-receptor complex binds to DNA which alters transcription

Question 8

What is the onset and duration of Steroid Hormones

Answer 8

Slow onset and long duration

Question 9

What are amino-acid derivative hormones

Answer 9

Modified Amino Acids

Question 10

What are common examples of amino acid derivative hormones

Answer 10

norepinephrine; epinephrine; triiodothyronine; thyroxine

Question 11

What are direct hormones

Answer 11

major effects on non-endocrine tissue

Question 12

What are tropic hormones

Answer 12

major effects on other endocrine tissue

Question 13

What is the hypothalamus

Answer 13

Bridge between nervous and endocrine system; stimulates the anterior pituitary gland through paracrine release of hormones into the hypophyseal portal system

Question 14

How are hormones regulated from the hypothalamus

Answer 14

Projections from other parts of the brain
Chemo- and Baro- receptors in blood vessels
Negative Feedback

Question 15

What is Gonadotropin Releasing Hormone

Answer 15

promotes the release of FSH and LH

Question 16

What is Growth Hormone Releasing Hormone

Answer 16

promotes release of Growth Hormone

Question 17

What is thyroid releasing hormone

Answer 17

promotes release of Thyroid stimulating hormone

Question 18

what is corticotropin releasing hormone

Answer 18

promotes release of adrenocorticotropic hormone

Question 19

what is prolactin Inhibiting factor (PIF/Dopamine)

Answer 19

Inhibits release of prolactin

Question 20

What hormones does the posterior pituitary gland release after synthesis in the hypothalamus

Answer 20

Antidiuretic hormone and oxytocin

Question 21

What hormones does the hypothalamus release

Answer 21

GnRH
GHRH
TRH
CRF
PIF

Question 22

What hormones does the anterior pituitary gland release

Answer 22

FSH
LH
ACTH
TSH
Prolactin
Endophorins
GH

Question 23

What does follicle stimulating hormone do

Answer 23

promotes the development of the ovarian follicles in females and spermatogenesis in males

Question 24

What does luteinizing hormone do

Answer 24

promotes ovulation in females and testosterone in males

Question 25

what does adrenocorticotropic hormone do

Answer 25

promotes the synthesis and release of glucocorticoids from the adrenal cortex

Question 26

what does thyroid stimulating hormone do

Answer 26

promotes the synthesis and release of triiodothyronine and thyroxine from the thyroid

Question 27

what does prolactin do

Answer 27

promotes milk production

Question 28

what does endorphins do

Answer 28

decrease perception of pain and produce euphoria

Question 29

what does growth hormone do

Answer 29

promotes growth of bone and muscle and shunts glucose to these tissues; raises blood glucose concentration

Question 30

what is antidiuretic hormone

Answer 30

secreted in response to low blood volume/increased blood osmolarity; increases the reabsorption of water in the collecting duct of the nephron, increasing blood volume and decreasing blood osmolarity

Question 31

what is oxytocin

Answer 31

secreted during childbirth and promotes uterine contractions; also promotes milk ejection; has a POSITIVE feedback loop

Question 32

What hormones does the thyroid release

Answer 32

T3; T4; Calcitonin

Question 33

What does triiodothyronine and thyroxine do

Answer 33

T3 and T4 are produced by follicular cells and contain iodine; they increase basal metabolic rate and alter utilization of glucose and fatty acids

Question 34

What is calcitonin

Answer 34

produced by parafolliuclar/C-cells of the thyroid; decreases plasma calcium concentration by promoting gut calcium excretion in the kidneys, decreases calcium absorption in the gut; promotes calcium storage in the gut

Question 35

What does the parathyroid gland release

Answer 35

parathyroid hormone

Question 36

what does parathyoid hormone do

Answer 36

1) decreases excretion of calcium by kidneys and increases bone release of Ca to increase blood Ca 2) Activates Vitamin D (necessary for Ca and phosphate absorption in the gut) 3) promotes release of phosphate from bone and reduces reabsorption of phosphate in the kidney

Question 37

What hormones does the adrenal cortex release

Answer 37

glucocorticoids; mineralocorticoids; cortical sex hormones

Question 38

what are glucocorticoids

Answer 38

cortisol and cortisone; increase blood glucose concentration, reduce protein synthesis, inhibit immune system, and participate in stress response

Question 39

what are mineralocorticoids

Answer 39

Aldosterone; promote sodium reabsorption in the distal convoluted tubule and collecting duct (increases water reabsorption); increases potassium and hydrogen ion excretion

Question 40

how are mineralocorticoids regulated

Answer 40

renin-angiotensin-aldosterone system

Question 41

what are cortical sex hormones

Answer 41

Androgens (testosterone) and estrogens

Question 42

What does the adrenal medulla release

Answer 42

catecholamines (norepinephrine and epinephrine)

Question 43

What do the catecholamines do

Answer 43

promote glycogenolysis, increase basal metabolic rate, increase heart rate, dilate bronchi, and alter blood flow

Question 44

what hormones do the pancreas release

Answer 44

glucagon, insulin, somatostatin

Question 45

what does glucagon do

Answer 45

produced by alpha cells; raises blood glucose by stimulating protein and fat degradation, glycogenolysis, and gluconeogenesis

Question 46

what does insulin so

Answer 46

produces by beta cells; lowers blood glucose by stimulating glucose uptake by cells and promoting anabolic processes like glycogen, fat, and protein synthesis

Question 47

what does somatostatin do

Answer 47

produced by delta cells; inhibits insulin and glucagon secretion

Question 48

what hormones do the gonads release

Answer 48

testosterone (testes) and Estrogens/progesterone (Ovaries)

Question 49

what does the pineal gland release

Answer 49

melatonin for circadian rhythms

Question 50

What does the stomach and intestines release

Answer 50

secretin, gastrin, and cholecystokinin

Question 51

what does the kidneys secrete

Answer 51

erythropoietin which stimulates bone marrow to produce erythrocytes in response to low oxygen levels in the blood

Question 52

What does the atria of the heart secrete

Answer 52

atrial natriuretic peptide which promotes excretion of salt and water in the kidneys in response to stretching of the atria (high blood volume)

Question 53

what does the thymus secrete

Answer 53

thymosin which is important for proper T cell development and differentiaion