Excretion Flashcards
what is urea
nitrogenous waste product of the breakdown of excess amino acids in the liver, urea is poisonous
what is deamination
breakdown of excess amino acids in the liver( protein cant be stored so its
how is urea removed
- urea passes from the liver cells to blood
- filtered out of the blood by the kidneys
- passed out of the body in urine produced by kidneys along with any excess water and salt
excess protein can’t be stored so is broken down by deamination by liver into ammonia –> very toxic
eventhough urea is also toxic, the body has a mechanism to remove it
what are te 2 sphincter muscles function
first muscle is involuntary and opens when the bladder has no more room, and second sphincter muscle relaxes and alert someone that they need to pee
go and label urinary system
search diagram and find answers
go and label kidneys diagram
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what is cortex
outer layer of the kidneys which contains tiny blood vessels which branch of the renal artery and the nephron
what are nephrons
the filtering units of the kidney
what are medulla
middle section of the kidneys down which the nehprons run
pyramids
bulges found in th medula, funnel like things which the nephrons run down into the renal pelvis
what is the renal pelvis
centre of the kindey where the urine is emptied into which also has ureters connected
ureters
tubes branching from the renal pevis into the bladder
The bowman’s capsule
at the start of the nephron - a hollow cup of cells which surround the glomerulus
Glomerulus
a ball of blood vessel where blood is filtered
Basement memebrane
a layer inbetween the glomerulus and the bowmans capsule keeping all the cells together
what substances can pass through in the ultra filtration process
salt ions, urea, water glucose and small molecules, ( big molecules cant pass through like blood cells and proteins)
glomerular filtrate
the liquid in the capsule after the filtration
ultra filtration
the process where different size molecules are filtered under pressure
what is the proximal convulated tubule(PCT)
this is where all the usefull substances are reabsorbed into the blood ( selective reabsorption) like glucose, water and sodium ions, uses active transport
loop of henle
makes the filtrate more concentrated by causing the reabsorption of water into the blood
what is negative feedback
a system that works to maintain a steady state, does this by responding which oppose the inital change
what is antiduiretic hormone(ADH)
a hormone in the body which is released by the pituitary gland in response to low water concentration within the blood
when there is less water in the blood
osmoreceptors in the hypothalamus detect this
pituitary gland releases lots of ADH into the blood
Affects the kidney tubules so they reabsorb a lot more water
results in a small, concentrated volume of urine
when there is more water in the blood
osmoreceptors in the hypothalamus detect this
the pituitary gland releases less ADH into the bloodstream
this affects the kidney tubules and they reabsorbing less water
results in a large, dilute volume of urine.
