Urinary System Flashcards
What are the three main waste products found in urine?
urea, uric acid, creatinine
What is creatinine?
waste product from muscle metabolism
What is the functional unit of the kidney?
nephron
What is the glomerulus?
knot of capillaries at the beginning
What is the Bowman’s capsule?
structure housing the glomerulus?
What is the plasma called after it enters Bowman’s capsule?
filtrate
What are the three processes used to make urine?
filtration, reabsorption, secretion
What is filtration?
blood pressure forcing plasma into Bowman’s capsule
What is secretion?
taking some substances out of blood and adding it to filtrate
What is the first portion of the nephron, after the Bowman’s capsule?
proximal convoluted tubule
Where does most reabsorption/secretion take place?
proximal convoluted tubule
What is the purpose of the loop of Henle?
to reabsorb water
How does the loop of Henle accomplish water reabsorption?
by taking in salt and creating a gradient, to bring in more water
What comes after the loop of Henle?
distal convoluted tubule
What is the purpose of the distal convoluted tubule?
for urine fine-tuning
Which hormone affects the distal convoluted tubule?
aldosterone
What does aldosterone do?
increases reabsorption of sodium, thus increasing water reabsorption
What is the final portion of the nephron?
collecting duct
How do the kidneys primarily regulate blood pressure?
enzyme renin, which causes production of chemical that constricts blood vessels to increase pressure
What is the name of the chemical produced by renin?
angiotensin II
What else does angiotensin II do?
increases aldosterone production, which increases sodium intake, which increases water intake, which inflates blood volume, which increases pressure
Fish excrete nitrogen wastes in which form?
ammonia
Adult amphibians, turtles, humans, and other mammals excrete wastes in which form?
urea
Reptiles and birds excrete wastes in which form?
uric acid
