M31: Endocrine System Overview Flashcards
name the 5 endocrine only glands
- pituitary gland
- pineal gland
- parathyroid glands
- thyroid gland
- adrenal glands
“master gland” of the body
pituitary gland
“master gland”
pituitary gland
pineal gland location + function
part of epithalamus
- secretes melatonin (helps with circadian rhytm)
thyroid gland location + function
surrounds trachea
- regulate metabolism
parathyroid glands location + function
back of thyroid gland
- regulate ion levels in blood, specifically Ca2+
adrenal gland location + function
top of kidneys
- release hormones apart of ANS
- releases ALDOSTERONE (regulates ion concentration in kidney tubules)
endocrine vs exocrine glands
EXOCRINE
- secrete products into ducts that empty into body cavities or surfaces
ENDOCRINE
- secrete products (hormones) into interstitial bloodstream
name other organs that secrete hormones as a second function
- hypothalamus
- thymus
- stomach, liver, pancreas, kidneys, small intestine
- ovaries, testes, placenta
- heart
- skin
- adipose tissue
4 general functions of hormones
- Help regulate
- Interstitial fluid composition
- metabolism
- blood glucose
- contraction of cardiac and smooth muscle
- immune functions - Growth and development
- Regulate reproductive systems
- Circadian rhythms
Target organs for specific hormones are determined by…
the specific type of receptor on the target tissue
down-regulation and up-regulation of hormones
DOWN: excess hormone causes a decrease in # of receptors -> decreased sensitivity
UP: deficiency of hormone causes an increase in the # of receptors -> increased sensitivity
circulating vs local hormones
CIRCULATING
- act on distant targets
- travel in blood
LOCAL
- PARACRINES: act on neighbouring cells
- AUTOCRINES: act on same cell (or cells like it) that secrete them
where do water soluble vs lipid soluble hormones bind onto cells?
water - cell surface
lipid - inside the cell
how may cells respond to hormone binding?
(5 ways)
- synthesis of new molecules
- changing permeability of cell membrane
- transport substance in/out of cell
- altering metabolic actions
- causing contraction of smooth muscle
what mechanisms regulate hormone secretion?
- signals from nervous system
- chemical changes in blood
- other hormones
most hormone regulation is achieved by _____ feedback
negative
T/F: secretion of hormones occurs in short bursts
true!
pituitary gland location
brain, attached to hypothalamus via the INFUNDIBULUM
thymus stucture + function
- endocrine and other function
- part of lymphatic system, helps with immune function, specifically maturing WBCs
endocrine function of the lungs
releases ACE enzyme, part of the renin angiotensin pathway
endocrine function of the heart
releases atrial natriuretic peptide (ANP)
which helps to regulate blood pressure
endocrine function of the stomach
releases GASTRIN into blood, regulates gastrointestinal function
endocrine function of liver
produces angiotensinogen, precurser for angiotensin II
endocrine function of pancreas
produces insulin and glucagon
endocrine function of small intestine
secretes CCK and secretin
endocrine function of the kidneys
produce rennin (a part of the rennin-angiotensin pathway)
endocrine function of skin
produces vitamin D
endocrine function of ovaries and testes
produce sex hormones for the body
why can one hormone have different effects on different tissues?
different target tissues have different receptors that are linked to specific actions inside the cell
paracrine hormones
local, act on neighbouring cells
autocrine hormones
local, act on the same cell that produces it
