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Ch 44-45 - Coggle Diagram
Ch 44-45
CH 45: Endocrine system
chemical signaling by hormones
two basic systems for communication and regulation: Endocrine and Nervous System
types of communication pathways
endocrine: glands that secrete chemicals to blood
exocrine: glands that secrete outside of the body/ tubes outside of the body
paracrine: glands/ chemicals affect nearby cells
ex: interferon
autocrine: only affects cells that secrete it
types of communication chemicals
neurotransmitter: chemical messenger of brain (css), central nervous system,pns (nerves)
hormone: chemicals signals that travel through blood.
steroids: lipid based chemicals ( estrogen, testosterone)
non polar pass through cell membranes
polypeptides: partial proteins ( insulin, bacteria (CRISPR), most hormones
polar ( only receptor cell)
amines: amino acids
other compounds that act as hormones are gases (nitrous oxide), viagra, ATP
neuroendocrine pathway: 3 part process: hypothalamus> pituitary gland> other glands
Location & action of target receptors
water-soluble hormones act on: cell membrane receptors release G proteins, activate enzyme
proteins, amines, peptides
lipid-soluble hormone action: steroids - non polar: enter cell, bind to DNA
Hormone effects
stimulation: increases metabolic activity
inhibition: slow down/ stop metabolic activity
agonists: hormones increases effect of another hormone (amplifies) positive feedback
antagonists: hormone cancels out another hormone
effects of hormone deficiency or overload
down-regulation: occurs when too much of a hormone casues a cell to reduce receptors
ex: type 2 diabetes
less sensitive
up-regulation: when you don't produce enough of a hormone, cells are more sensitive causing a stronger effect on a person
The nephron is organized for stepwise processing of blood filtrate
Process:
glomerulus >bowman's capsule > proximal tubule > loop of hence > distal tubule > > collecting duct
filtrate travels through the tubes
ions are reabsorbed
other proteins and molecules are get filtered, body keeps what it needs
countercurrent multiplier: two fluids move opposite direction , improves exchange of materials
helps concentrate urine in mammals
The loop of Henle maintains the interstitial gradient of NaCl, which increases continuously in concentration from the cortex to the inner medulla
Bats: produce large amounts of liquid , concentrate urine
birds/reptile: keep water
freshwater fish/ amphibians: dilute urine, pee all the time
marine fish: don't excrete lots of urine gills are used for excretion
environmental factors
salt water
freshwater
land
Hormonal circuits link kidney function, water balance, & blood pressure 44.5
hypothalamus gland
produces ADH (anti-diuretic hormone)
triggered by dehydration, body tries to retain water
a drug that inhibits adherence to would make you urinate frequently
Renin angiotensin aldosterone system
regulates blood pressure which ends up regulating blood volume
kidneys, liver, lungs, adrenal glands are involved in this system
JGA ( juxtaglomerular apparatus)- releases enzyme renin
renin- initiates sequence of steps that cleave palm protein called angiotensin, yielding a peptide called angiotensin II
both ADH and RAAS increase water reabsorption in the kidney
adh lowers blood NA+ concentration via water reabsorption in kidney
RAAS helps maintain body fluid osmolarity within the normal range stimulating NA+ reabsorption
Osmoregulation & Excretion
osmoregulation balances the uptake & loss of water & solutes 44.1
Osmosis
momevent of water through semipermeable membrane from low to high concentration
ex: sprinkle salt on slug , slug will shrivel up and dry since the salt will draw the water out.
ocean water will dehydrate you if you drink it due to high concentration of salt in the water, blood pressure will go up and will have to urinate more.
osmoregulation
regulation of water by regulating ions
salt & water regulation
water follows salt
birds excrete excess salt through their beak
osmolarity in human blood is .09%
can change by consuming lots of salt, sweating, kidneys
if you gave someone distilled water & they're dehydrated their cells would become hypotonic, cells would burst
osmolarity
measure of total concentration of solute particles in solution
osmoles - units of measurement
osmoconformer
to be isotonic with its surroundings - ex: marine animals
osmoregulator
maintain water balance, controls internal osmolarity independent of the external environment. Regulate salt and water concentration.
Terrestrial animals goal is to keep water in the body, prevent dehydration
freshwater animals are trying to keep water out, barely drink water and excrete filtered urine
tardigrades
animals that becomes dormant when dehydrated by process called anhydrobiosis
anhydrobiosis- life without water
An animal's nitrogenous waste reflect it's phylogeny & habitat 44.2
Nitrogenous waste
waste that contains nitrogen
comes from excess proteins
3 types of excretion of nitrogen
ammonia
aquatic animals
need access to lots of water
urea
mammals , some amphibians
low toxicity high solubility in water high water conservation, high energy consumption to be excreted
uric acid
birds and reptiles
very little water loss, high energy consumption
excretion
metabolic waste must be dissolved in water in order to be excreted
Diverse excretory systems are variations on a tubular theme 44.3
Excretory process
Filtration
filtrate
passive
movement of water solutes through a semi permeable membrane due to hydrostatic pressure
reabsorption
reabsorb ions body wants to keep
passive/ action movement of waterr & solutes from filtrate (tubule) into blood
secretion
secrete waste
secretin- active movement of water/ solutes from the blood into tubule system
excretion
urine out of the body
Platyhelminthes
protonephridia- dead end tubules that branch throughout the body
annelids
metanephridia- excretory organs that collect fluid directly from the coelom
insects/ arthropods
Malpighian tubules- remove nitrogenous wastes that also function in osmoregulation
vertebrates/ chordata
kidneys- functions in both osmoregulation and excretion
