endocrine system Flashcards
what does the endocrine system consist of
-glands tissue that secretes to make hormones
-hormones are chemical to set something in motion or stop something
4 classes of hormone
- autocrine: make itself reproduce to fight infection (white blood cells)
- paracrine: local, does something in 1 spot (WBC release histamine to cause vasodilation)
- neurotransmitter: neuron to neuron or muscle or gland
- endocrine: released into blood stream and goes everywhere
major functions of the endocrine system
- growth
- sextual development
- mood
- metabolism
- effect how organs work
difference between endocrine and exocrine
endocrine: goes into the blood…deposits chemical directly to blood stream…everywhere
exocrine: puts chemical/fluids into duct to a specific place
endocrine system
- not as fast… seconds to weeks
- what cause can happen for seconds to weeks
- broadcast
- chemicals called hormones
- intensity is concentrated
- not nerve cells
- release secretion into blood
- no vesicles
- some get inside cells
nervous system
- very fast…milliseconds
- continue as long as messages continue
- specific
- chemicals called neurotransmitters
- brain, spinal cord
hormones modify internal biochemical operations within target cells by
influencing intracellular enzymes
a given hormone will only affect certain cells
determined by presence or absence of a receptor
several different structural categories of hormones, structural differences have functional implications
the way hormone is put together influences what can do
- some hormones interact with receptors on surface of cell
- other hormones diffuse into the cell to ______
- some hormones need help moving through the blood
peptide/proteins
- most of hormones are this type
- water soluble…get to bloodstream faster
- small
- lot of medicine(current) is focused on these
- produced by pituitary gland and thyroid gland produce lot of those
peptide continued
made with amino acids with peptide bonds
can’t get into the cell, therefore have to bind with receptor on the outside, secondary messenger in cell tells nucleus to change
travel and life span of peptide hormones
most travel freely through blood, smaller travel with a protein (because broken down easier)
tend to have short half-life…2-30 min
steroids
lipids, fat soluble…testes and ovaries
made with: cholesterol - make hormones
can get into the cell because fat soluble, receptor inside instead of outside
travel and life span of steroids
attach to proteins, can’t move by themselves
half-life ranges days to weeks
amino acid derivatives/tyrosine derivatives
made with just one type of amino acid: tyrosine, come from thyroid and adrenal cortex
can act like steroids and peptides
thyroid hormone: lipid soluble/fat soluble
catecholamines: water soluble, made in adrenal glands
target cells
where the hormones are going
hormones go here to change how operates…target cell does something different
hormone hits a receptor and nucleus decides what to do
receptors
either on outside or inside
water soluble…hormone receptor outside
lipid soluble…hormone receptor on inside
negative feedback
hormones work on negative feedback, something changes, hormones sent to change
- cells respond to changes in extracellular fluid by releasing hormones when fluid goes back to normal, hormone production stops
hypothalamus
ultamily in control of whole system
- king in control, not that much work
- synchronizes endocrine and nervous system
pituitary gland
master gland…do all the work
small
divided front and back
anterior pituitary gland
hypothalamus link: got hormones coming out of nervous system (RH & IH) get picked up by capillary and immediately dumped into capillaries
portal system: not using whole circulatory system
negative feedback to hypothalamus
presence of hormones after circling back turns off hypothalamus…in turn turns off anterior pituitary gland
TSH
thyroid stimulating hormone
turning thyroid on
ACTH
adrenocorticotropic hormone
adrenal gland…adrenal cortex
causes adrenal to release cortisol
FSH
follicle stimulating hormone
- testes and ovaries
turn on testes or ovaries…making sperm or eggs
LH
luteinizing
cause ovulation in women
production of testosterone in men
PRL
prolactin
make milk
cause mammary glands to produce milk
GH
growth hormone
all cells grow and reproduce…specifically skeletal muscles
tend to have more when sleep, make more after exercise and trama
MSH
melanocyte stimulating hormone
produce skin pigment
posterior pituitary gland
contains axons from neurons from hypothalamus
2 hormones…
ADH - anti diuretic (keep water) tells kidneys not to take as much water out
oxytocin - stimulates labor, allows milk to be released, emotional bonding during sex
thyroid gland
in neck, throat in front of trachea
shape: looks like butterfly
goiter: swelling in thyroid gland…hard to swallow…caused by lack of iodine
tyroxine
T4
4 iodine attached to molecule
80% of what thyroid makes is T4
amino acid
Triiodothyronine
T3
3 iodine attached to it
10% of what thyroid makes is T3
amino acid
what do T4 & T3 do?
doing basically same thing…
- increase production of ATP in mitochondria
- increasing metabolism
- effect on body temp and heart rate
calcitonin
peptide
reducing calcium in blood…helps keep bones strong
- allow kidney to get rid of some
- decrease osteoclast activity
if too much can end up with kidney stones
10% of what thyroid produces
parathyroid glands
attached to thyroid…4 spots that are doing different stuff
also about calcium
PTH
parathyroid hormone
opposite of calcitonin
increase calcium in blood
- inhibit osteoblast
- increase osteoclast
- tell kidney’s to not get rid of so much
adrenal cortex
outer layer- looks yellow because of the amount of fat stored (cholesterol)
- making steroids…about 2 dozen, collectively call corticosteroids
corticosteroids
cortisol- stress hormone…“enemy of weight loss”
anti inflammatory
vasoconstriction- blood vessels get smaller so blood pressure goes up
suppress immune system
effect mood…stress and anxiety
adrenal medulla
inside of adrenal gland
controlled by the sympathetic nervous system(arouse/excite, fight or flight)
…fast, 30 seconds, last for 30 min-hour…adrenalin
produces 2 hormones
2 hormones produced by adrenal medulla
epinephrine
- help us use energy/increases ability
- increase glucose use
- increase heart rate
- muscles stronger
norepinephrine
-increase heart rate let glucose out so can use
- increase blood pressure, get blood to muscle
pineal gland
in brain, very small, roof of thalamus…deep in brain
makes melatonin…help with sleep, is antioxidant…help prevent cancer
vision effects melatonin
goes down during puberty…why sleep less
pancreas
in digestive system
mainly exocrine, but some are endocrine
- islets of langerhans 1%-still about 1 mill cells
2 types…
alpha cells
- some make glucagon(increase glucose in blood)
beta cells
- make insulin(take sugar/glucose out of blood)
homeostasis of blood glucose levels
normal level = 70-110 mg/dl
(use 100 in class)
kidneys
mainly part of urinary system…does have 2 hormones it releases
- calcitriol: releases by kidney because of PTH, needs vitamin D, increase calcium digestion-get from digestive track into blood
- EPO: made by kidneys when oxygen levels get low…make red blood cells, more red blood cells means thicker blood and more endurance
Heart
cardiovascular system
ANP: atrial natriuretic peptide
cause kidneys to make more water and sodium
so can lower blood pressure
Thymus
lymphatic/immune system located by heart
thymosins: collection of hormones, not 1 hormone
when become adult this gland doesn’t work
anymore. help in the immune system making
white blood cells
Gonads
generic term for testes and ovaries
1. testosterone: both genders make, but women make less
- sperm production
- muscle mass
2. estrogen: both genders make, men make less
- women extra - in ovaries…production of eggs
- bone density…not enough estrogen, bones weak
Leptin: made in fat cells, supposed to tell the brain to stop eating(control appetite)
when blood sugar is up …
insulin is used to take back down to normal level
when blood sugar is down
glucagon is used to bring it up
blood sugar/insulin
- increase rate of glucose in the cells
- increased rate of glucose utilization
- increased rate of glucose into glycogen
- increased protein synthesis (put together)
- increased putting fat together
blood sugar/glucagon
- increased breakdown of glycogen into glucose
- increased breakdown of fats
- increased synthesis of glucose by liver
integumentary system
testosterone promotes hair growth. estrogen promotes added fat
skeletal system
calcitonin and calcitriol regulate calcium
muscular system
GH and testosterone increase size of skeletal muscles
nervous system
testosterone and estrogen can influence mood and behavior
cardiovascular system
EPO increases RBC. epinephrine increases heart rate
lymphatic system
Thymosins make WBC
respiratory system
epinephrine opens airways
digestive system
calcitriol helps digest calcium
urinary system
ADH increases water retention. ANP increases water excretion
reproductive system
FSH and LH regulate testes and ovaries
