excretory system Flashcards
what is the function of the kidneys
regulates water concentration in blood
excretes toxic waste
(kidneys)
what does the renal vein and artery do
supply blood to and from the kidney
(kidneys)
what is the milus
opening into the kidney, where substances enter and leave
(kidneys)
what does the ureter do
muscular tube
transports urine from kidneys to bladder
(kidneys)
s + f of cortex
red / brown, rough texture
filtration happens here
(kidneys)
s + f of medulla
dark purple
filtration here
what are kidneys made up of
tiny structures called nephrons that carry out kidneys functions
(kidneys)
what does the renal pelvis do
collects urine
what is the structure of a nephron
a knot of capillaries (glomerulus) inside a hollow ball called the bowmans capsule
how does selective reabsorbtion work
Useful substances leave the nephron tubules and enter the capillary network which surrounds the nephron. The tubules in t is network have microvilli for more surface area and more absorbtion
how do nephrons work
high pressure within the glomerulus forces small molecules and fluid (flitrate) into the bowmans capsule. Any materials still required by the body are later reabsorbed by diffusion in the capillaries surrounding the tubule
what is the loop of henle
Descending:
Permeable
25% of water and salt reabsorbed back into the blood.
Ascending:
Non- permeable to water due as it is thicker.
Once water is in the ascending tubule it can’t be reabsorbed.
where is adh made
Hypothalamus
where is adh stored
pituitary gland
what does adh do
promotes reabsorption of water from the collecting duct back into the blood.
when is adh released
during dehydration
what is urea
a waste product of urine, it needs to be removed from the body
structure and function of the ureter
muscular tube from penis to bladder, moves urine from kidneys to bladder
s + f of bladder
hollow, triangle shaped
collects, stores and releases urine
what part initiates urination
motor cortex
