Introduction to endocrinology

Question 1

Hormone definition

Answer 1

Chemical substance secreted by a gland, group of glands, tissue
has a physiological control effect on other cells of the body

Question 2

endocrine definition

Answer 2

secretes within the body

Question 3

exocrine definition

Answer 3

secretes outside the body

Question 4

how much time does it take to see hormonal effects

Answer 4

seconds (norepinephrine, epinephrine)
days weeks
months (thyroxine, GH)

Question 5

how does the nervous system interact with the hormonal system

Answer 5

sympathetic nervous system can stimulate adrenal glands
CNS can control the pituitary gland
some hormones are controlled by the nervous system

Question 6

what functions of the body does the endocrine system control (4)

Answer 6

chemical reaction rate of cells
transport of substances through cell membranes
growth of body
secretion of other hormones

Question 7

pituitary gland anatomy

Answer 7

two halves
anterior controlled by other hormones and secretes 6 hormones
posterior pituitary under neural control and secretes 2 hormones

Question 8

what 6 hormones does the anterior pituitary secrete

Answer 8

GH
adrenocorticotropin
thyroid-stimulating hormone
follicle-stiulating hormone
luteinizing hormone
prolactin

Question 9

what 2 hormones does the posterior pituitary secrete

Answer 9

antidiuretic hormone
oxytocin

Question 10

Adrenal glands

Answer 10

2 glands, 1 on top of each kidney
each gland has 2 parts
adrenal cortex under hormonal control and secretes 2 hormones
adrenal medulla under neural control and secretes 2 hormones

Question 11

what hormones does the adrenal cortex secrete

Answer 11

cortisol
aldosterone

Question 12

what 2 hormones does the adrenal medulla secrete

Answer 12

catecholamine hormones
adrenaline
noradrenaline

Question 13

what hormones does the thyroid secrete

Answer 13

thyroxine (T4)
triiodothyronine (T3)
calcitonin

Question 14

parathyroid glands

Answer 14

4 small glands located within the thyroid
secretes 1 hormone

Question 15

what hormone does the parathyroid secrete

Answer 15

parathormone

Question 16

islets of langerhans

Answer 16

in the pancreas
endocrine tissue
secrete several hormones like insulin glucagon

Question 17

ovaries

Answer 17

endocrine gland
produce estrogen and progesterone

Question 18

testicles

Answer 18

produce testosterone

Question 19

placenta

Answer 19

endocrine tissue
secretes human chorionic gonadotropin
estrogens
progesterone
somatomammotropin

Question 20

duodenum

Answer 20

contains brunners glands
secretin hormone
coordinates digestion

Question 21

brown adipose tissue

Answer 21

receives hormonal input to help regulate body temp
not gland or tissue

Question 22

local hormones

Answer 22

specific local effects on specific tissues

Question 23

secretin

Answer 23

released from duodenal wall transported in blood to pancreas
cause pancreas secretions for digestion

Question 24

cholesystokinin

Answer 24

released in small intestine transported to gall bladder and causes gallbladder contraction
pancreas cause secretion of digestive enzyme

Question 25

adrenocorticotropin

Answer 25

released from pituitary gland stimulates adrenal cortex to secrete adrenocortical hormones

Question 26

general hormones

Answer 26

effective on many parts of the body and cause many different reactions ex: epinephrine, T3 T4 and GH

Question 27

hormones classified on their basic chemical structure

Answer 27

steroid protein tyrosine

Question 28

steroid hormones

Answer 28

based on the cholesterol molecule hydrophobic lipophilic crosses easily plasma membranes of cells

Question 29

where are the receptors for steroid hormones

Answer 29

within the cell cytoplasm or nucleus

Question 30

pathway of steroid hormones

Answer 30

hormone enters the cytoplasm of the cell binds with a receptor diffuse or transported into nucleus bind to and activate DNA strands initiate transcription process of genes to form RNA messenger RNA goes into cytoplasm through nuclear pore complex promote functions inside the cells

Question 31

epinephrine and norepinephrine

Answer 31

secreted by adrenal medulla under sympathetic stimulation secreted by sympathetic nerves causes constriction of blood vessels and increase of arterial pressure has effects on most organs and tissues of the body

Question 32

growth hormone

Answer 32

released from anterior pituitary cause growth in all parts of the body

Question 33

thyroid hormone T3 and T4

Answer 33

released from thyroid gland increase chemical reaction rate in almost all body cells

Question 34

tyrosine based hormones

Answer 34

important amino acid to make proteins thyroid gland turns tyrosine into T3 and T4 adrenal medulla can turn tyrosine into epinephrine and norepinephrine

Question 35

how does the thyroid gland use tyrosine

Answer 35

adds iodine molecules to tyrosine to make t3 and t4

Question 36

how does the adrenal gland use tyrosine

Answer 36

hydroxylates tyrosine to make it hydrophilic

Question 37

where are the receptors for t3 and t4

Answer 37

inside the cells

Question 38

chain of events of thyroid hormones

Answer 38

TH binds with receptor in cell nucleus bind and activare DNA initiate transcriptions of specific genes to form RNA messenger RNA goes into cytoplasm through nuclear pore complex new proteins (enzymes) are formed and become the controller to promote metabolic activities in all cells of body

Question 39

what tyrosine based hormones need to interact with a receptor on the cell surface

Answer 39

E NE Ach

Question 40

protein based hormones (example)

Answer 40

anterior pituitary hormones posterior pituitary hormones insulin and glucagon parathormone

Question 41

protein based hormones

Answer 41

hydrophilic receptors at the surface of cell membrane

Question 42

protein based hormones chain of events

Answer 42

bind to receptor structure change in receptor receptor becomes activated enzyme adenyl cyclase activate the formation of cAMP second messenger activates cascade of enzymes

Question 43

second messenger

Answer 43

cell-signaling pathways that communicate between the receptor on the cell surface and the inside of the cell

Question 44

second messenger example

Answer 44

cAMP Ca2+-calmodulin IP3 and diacylglycerol

Question 45

t/f concentration of hormones is extremely low in blood

Answer 45

true

Question 46

how can hormones be measured

Answer 46

radioimmunoassay RIA mass spectrometry

Question 47

RIA

Answer 47

the higher the percentage of bound radioactive hormones, the lower the concentration of the natural hormone to be measured

Question 48

mass spectrometry

Answer 48

very precise but hard and expensive

Question 49

secretion rate of hormones

Answer 49

body can control how much effect the hormone is having homeostasis

Question 50

what is the most common way of controlling secretion rate

Answer 50

negative feedback inhibits its own secretion when level is high enough

Question 51

direct negative feedback

Answer 51

hormone inhibits its own secretion when there is enough of it

Question 52

indirect negative feedback

Answer 52

when the effect of the hormone inhibits the secretion

Question 53

direct positive feedback

Answer 53

hormone goes back to the gland to promote secretion

Question 54

indirect positive feedback

Answer 54

effect promotes the secretion

Question 55

circadian rythm

Answer 55

when we sleep different hormones go up and down

Question 56

hormone receptor regulation

Answer 56

receptors can be activated or deactivated by altering their second messenger receptors can be destroyed by enzymes receptors can be created by synthesis