homeostatic regualtion Flashcards
define homeostasis
use example of pos and neg feedbakc
intro
regulation of internal body condition
is regulated using pos and neg feedback, mainly neg
What is set point
inttro
The point around which the normal range fluctuates
ex set point of human temp is 37C
what is normal range
intro
the range of values that is optimal (healthy and stable) for a particular species
ex normal range for human temp is 36.1°C –37.2°C
what is caveat of setpoint and normal range
intro
often determined by a number of factors
sex, age, time of day, diet
nervous system vs endocrine system
also how do they relate
intro
Nercvous sys - for rabid respons
endocrine - for long term respons (with hormones
enodcrine sys is part of autonomic PNS )
what is target / effector cell
intro
Cell that responds to the regulatory signal
performs bodys response to hormone signals
what is hormone/types 2
what its made of, solubility, where recept
intro
steroid - cholesterol, insoluble in water ,bind intracellularly to cytplasm or nucleus
peptide - short peptide seq, water soluble, bind to receptor on surface of target cell
What is the normal progression of steps in hormone control pathway
(Endocrine,Neurohormone,Neuroendocrin)
intro
stimulus
gland/hypothalamus
blood vessel
target
response
add 2 steps for neuroendocrine
what are the diff pathways of hormone control
difine them
intro
endocrine - only in endo, uses gland
neurohormone - only in NS, uses hypothal
neuroendocrine - uses both, hypothal then gland
endocrine glands vs exocrine glands
ex
intro
endo - organs make hormones, delivered by blood(pancreas and insulin)
exo - organs making hormones delivered by ducts (salivary glands)
function of hypothalamus and pituitary gland
intro
hypo - has neuroecretory cells, makes hormones, not synapse
pituit post - secretes horms from hypo
pituit ant - makes and secrete horms
for diff hormonal pathways
locate ant and post pituitary
intro
anterior is closer to the phallic thing
posterior thing is farther away
what is neurosecretory cell
intro
nerve cell that makes hormone, secretes into blood
instead of neurotransmitters for synapse
posterior vs anterior gland
what hormons (2,6)
intro
post - part of nervous system, hypothal gives hormones, only secretes, does not make hormone (ADH, oxytocin)
Ant - seperate from hypothal, makes hormones (TSH, ACTH, FSH/LH, Growth H,PRL), regulated by hormones from hypothal
what is a tropic hormone
ex
intro
target other endocrine glands, not target cell
stimulate synth and release of hormones from other glands
antiorior pit - ACTH(long term stress), GH, TSH, FSH
what are main functions of ex sys
ex sys
osmoregulation
manage body water content
manage solute amount
control movt of of solutes
What is metabolic waste?, types
ex sys
by product of cell react
breakdown of protein
not feces
nitrogeneous waste (ammonia, urea, uric acid)
COmpare the types of nitrogenous waste
solub, toxic, synth, orgs
ex sys
ammonia - solub, toxic,when liver breaks down proteins, fish
urea - low toxic , combinatin of ammonia, CO2, highly sol in wat
uric acid - from nucleic acid, nontoxinc, insoluble in wat, birds
Why do birds and reptiles excrete urine as uric acid
ex sys
birds: for less weight, less water loss
reptile: keep water in hot climate, stop reabsorbtion in egg
What are the 5 types of bodily fluids in body
ex sys
total bodily water - tbw (all of it)
intercellular - icf (cells and blood vessels)
extracellular - ecf (everything but blood cells and cells)
plasma - type of ecf (fluid in blood stream)
interstitial- type of ect (liq inside body, bathing cells, )
anatomy of kidnay and nephron
also blood flow in each
kidney - renal medulla (lower), renal cortex (upper), renal pelvis, ureter
How does blood flow in kidney and nephron
7
ex sys
Nephron: renal art, afferent arteriole, cap of glom, efferent arteriole, peritub cap, vasa recta, rena lvein
Kidney: renal artery, exits by renal vein
what is pathway of filtrate , also purpose
9 bpldcrubu, no purp for last 4
ex sys
bormans cap - filtration
Proximal convoluted tub - reab, sec
Loop of Henle - reab
Distal convoluted tubule -reab, sec
Collecting duct - reab ex
Renal pelvis
Ureter
Bladder
Urethra
waht does glomerulus and bowmans capsule do
ex sys
glomerulus - ball of capilaries in bowman cap
bowmans cap - start of tubule , surrounds glomerulsu
take the filtrate from the blood (vitamins, salt, water, sugar nitrogenous waste)
secretion vs excretion
ex sys
sec - movt of subs from blood to excretory tubule, eventually excreted
ex - when filtrate exits body, then called urine
movt of subs reabsorption vs secretion vs filtration
ex sys
secret - when things enter tubule, leave blood, is eventually excreted
reab - leave tubule, go to blood, stuff stays in body
filt - glomerulus - > bowman cap, uses blood pressure,
anatomy and function of epithelium
ex sys
layer of cells that regulate solute movt
in intestines, kidney tubules
parts
apical memb - on cavity side of organ
basolateral - memb facing interstitial fluid
basement - memb anchors basolat and supports epit layer
What was permeability of Proximal tubule
purpose, 4 reab, 2 sec
ex sys
prox tub - reab h2o(p), K(p), Nacl(A),HCO3(P)
sec H(A), NH3(P)
Reabsorb important minerals
secreted determines pH
What is permeability of descending loop of henle, why
ex sys
Only permealble to water, passive
interstitial fluid is hyperosmotic
decrease osmo
to make solute more concentrated
Permeability of ascending loop of henle
ex sys
passive then reabsorption of NaCl
passive secretion of urea
makes filtrate more dilute
increase osmolarity of inner medulla
Describe permeability of distal tubes
also why
ex sys
Reab - H2O (P)(secondary), NaCL(A), HCO3-
Sec - K(A), H(A)
makes
Regulate pH and K, NaCl levels
Describe permeability of connecting duct also why
ex sys
Reabsorb - Permeable to H2O in CortexNaCl (A) in outer medulla, urea(p),H2O (P) in inner medulla
To concentrate filtrate, conservation of water
contributes to hyperosmotic env - drives reab of water
Permeability of H2O in the 6 parts of nephron
ex sys
bowmans cap - yes
proximal tube - yes
descending henle - yes, only water
Ascending henle - no
distal tube - yes
connecting tube - yes
all are reabsorbed
define osmoregulation
also relation to excretion and urine prod
osmoreg
management water amt in body - blood vol/pressure
management of solute concentration in bod - ph lvl
control of movt of solute from int fluids to ex env - metabolic waste excretion
used in nephron to control what is secreted and reabsorbed
What does concentrated or dilute urine imply about blood volume and osmolarity?
osmoreg
concentrated urine means high osmolarity, low blood volume
dilute means low osmolarity, high amt of fluid in blood, body wants to get rid of it
What are the 3 hormones in osmoreg
when are they made
osmoreg
ADH - high osmolarity
RAAS - low blood pressure/vol
ANF - high blood pressure/vol
What does ADH do, how made, where target
how does it work, type of horm
osmoreg
Antidiuretic hormone
high osmo
peptide hormone
made by hypothal, stored in posterior pit G
goes into blood, binds to surface of distal tub, connecting duct , attaches aquaporines to memb, allows water to be reabsorbed
opposes urination, to lower osmolarity, makes you thirsty
What would cause increased osmolarity in body
osmoreg
sweating, dehydration, salty foods, diahrrea
How is ADH part of feedback loop, what type
osmoreg
negative, caused by high osmolarity
high osmo -> signals osmorecept in hypothal -> make ADH -> become thirsty and drink / reabsorb more water - > increase water in blood - > decreases osmo
What does RAAS do, process
osmoreg
Renin Angiotensin Aldosterone System
for low BP and vol
detect by juxtaglomeruler app -> makes enz renin -> catalyzes stuff, makes angiotensin II -> contricts blood vess and cause release of aldosterone - > causes reab of sodium(increases osmolarity )
what is insipidus diabetes, symp, treatment
osmoreg
deficiency in ADH
symp - dilute urine, pee often, often thirsty
treatement - drink more water, take ADH pills
not the same as diabetes mellitus, urine not sweet
What is aldosterone, purpose, effects
where release, target, what does it stim
osmoreg
steroid hormone
released in outer layer of andrenal glad above kidney
target distal tube, increase NaCl,K reab, increase osmolarity
also stimluates ADH - reab of water,increase blood vol/pressure
describe neg feedback loop of RAAS
osmoreg
low Bpressure-> make renin->catalyze reaction, make angiotensinII -> contricts arterioles / release aldosterone(-> increase reab of salt) - > increase Bp
Why is RAAS needed
osmoreg
triggered when high blood loss, when ADH would not be triggered
blood loss would not increase osmolarity
What does ANF do
what does it inhibit
osmoreg
atrial natriuretic factor
when high blood pressure
from walls of atria in heart
peptide hormone
inhibit renin - > stops aldosterone
Inhibits NaCl reab -> decrease water reabsorbtion-> decrease blood vol/pressure
describe neg feedback loop of ANF
osmoreg
high Bp-> atria release ANF-> stops reab/inhbits renin(stops aldosterone)-> increases Bp
define thermoregulation
Thermoreg
regulation of internal body temp, keep within good reange
ex humans can live in diff temp and have constant body temp
ectotherms vs endotherms
Thermoreg
ecto - low metabolic rate, internal temp determine by env, fish, reptile
endo - high metabolic rate, can keep stable body temp, mammals birds
advantages/disadv of endotherm
Thermoreg
adv - can be active longer, can live in more env
dis - takes more eng, needs to eat more
what are adaptations for thermoreg
compare
Thermoreg
phys - fur, hair, feathers
behave - huddling, relocating
circulatory - counter current heat exch
What is counter current heat exchange
thermoreg
arteries with warm blood are close to the colder veins
happens in limbs so that the vein is warm by the time it gets to core
What are physiological adapt to diff temp
4
thermoreg
rate of heat exch
eveporative heat loss
rate heat production
rate metabolic heat prod
how is rate of heat exchange regulated
what type of thermoreg meth is it
Thermoreg
physiological
vasoconstriction, vasodilation
blood vessels shrink in cold
blood vessels expand in heat
helps retain or lose heat
what is evaporative heat loss method, type
Thermoreg
physiological
for cooling
sweating
how is rate of heat production regulated, type
Thermoreg
physiological
skeletal muscles contracts
shivering
How is metabolic heat prod regulated, type
Thermoreg
physiological
fat structure
white cells - single large lipid vacuole
brown cells- many small, only in endotherms, has lots of mitochondria
function of white fat cells vs brown fat cells
Thermoreg
white - storage, turn sugar into fat
brown - thermogenesis , mitochondria turn sugar into atp and heat, does not need insulin to get sugar
What are the 2 roles of pancraes
what cells make them
Horm gluc
exocrine cells - 99% by mass, make digestive enzymes for small intestine
endocrine cells - 1% by mass, make glucagen and insulin
What are the types of endocrine cells, funct
Horm gluc
found in islets of langerhans
alpha- make glucagon
beta - make insulin
what is insulins mech
stimulent, effect, result
Horm gluc
stim; hyperglycemia - too much glucose in blood (happens after eating)
ins enters blood from pancreas beta
insulin binds to cell
effect; exocytosis of GLUT4 to cell memb
cell takes in glucose with help of GLUT4 (glucose transporter)
lower blood sugar level
result; stops stimulus
negative feedback
what is glucagon stim, effect, result
what part of panc makes it
Horm gluc
stim - low blood sugar
effect - pancreas alpha release glucagon
liver increase breakdown of glycogen
glyc and amino acids converts to glucose
res - high blood sugar
decrease stim, neg feedback
label glucose homeostasis chart
Horm gluc
symp and causes of mellitus diab
why symp
Horm gluc
symp - hungry often, increase blood viscosity, less blood flow, sweet urine, freq urine, often thirst
cause - related to insulin, body cant make or use it
hungry - because cells arn’t getting enough eng
blood visc - more glucose in blood, makes thicker
sweet urine - glucose could not be filtered out, too much
causes and symp of mellitus diabetes type 1
Horm gluc
cause - immune sys attacks insulin making cells
decrease insulin levels
from childhood
autoimmune
causes and symp of mellitus diabetes type 2
Horm gluc
happens around 40
insulin receptors become unresponsive due to overuse
from obesity
why is frequent urination symp of mellitus diabetes
Horm gluc
to get rid of the extra glucose the kidneys need to work a lot, makes more urine
mellitus vs insipidus diabetes
Horm gluc
mell - sweet urin, stems from insulin problem
insi - dilute urine/not sweet, ADH deficiency, water is not reabsorbed enough
triggers of short vs long term stress
stress
short - immidiate response, fight or flight
long - long term response, can cause bad side eff, uses neuroendocrin path, cortisol
what are parts of adrenal gland that contribute to stress
loc, parts
stress
releases stress hormones
next to kidneys
ad cortex - outer part, for long terms stress
ad medulla - inner part, for short term
What are the steps in short term stress
name neurotrans and horm, what is inc or dec
stress
stress - nerve cells make neurotrans acetylcholine (ACh)
stims ad medulla to release epinephrine(adrenaline) and norepinephrine(noradrenaline)
stims fight or flight
effect: increase metabol, blood sug lvl
decrease kidney, digestation , mainly increase ox and eng
what is long term stress path
effect, result
stress
hypothal release corticotropin rel Horm (CRH)
ant pituitary rel - ACTH
Adrenal cortex - corticosteroids (Glucocorticoids (e.g. cortisol) Mineralocoritcoids (e.g. aldosterone)
effect - increase glucose and ox
What is corticotropin releasing hormone
made where, what type, used where, eff
Stress
CRH
part of long term stress pathway
first hormone of pathway. from hypothal
peptide horm, tropic
causes ant pit to release ACTH
what is adrenocorticotropic hormone
made where, what type, used where, eff
Stress
ACTH
for long term stress
made in ant pituitary
peptide tropic hormone
stims adrenal cort to make corticosteroid
what are cortiosteroids
types, funct of types, purp
made in ad cortex
for long term stress
2 types - glucocorticoid (cortisol) - increase gluc lvl, gets gluc from non carb source, anti inflam, suppress immune sys
mineralcorticoids (aldosertone) - sims reab of salt and water by kidn, increase blood pressure, increase ox delive
how does stress reg affect cell resp
gluc and ox
stress
short term stress - increases glucose breakdown from storage , increase metabolic rate, increase blood press - > increase ox to cell
long terms stress - glucocortinoids make glucose and will use proteins if needed, increase oxy vol
overall increases
What ar the parts of feedback loop
Example of pos feedback in human
pregnency
when stim triggers pathway that increases stim.
ex of neg feedback
When the stim triggers pathway that decreases stim
