Excretory System Flashcards
what are the main functions of the kidneys?
- excrete waste
- maintain homeostasis of body fluid volume & solute composition
- regulate blood pressure
def: monitors filtrate pressure in kidney tubules
macula densa
what happens if blood pressure is low?
- adrenal cortex signalled to synthesize aldosterone
- more water is reabsorbed from kidney back into the blood
- blood pressure increases/normalizes
def: hormone that increases Na+ absorption from kidney tubules into the blood stream, causing water to follow Na+ out of the kidney and back into blood, increasing water retention in blood
aldosterone
def: hormone that increases collecting duct permeability to water, water is reabsorbed out of kidney tubule and back into the blood stream, making urine more concentrated while blood pressure increases
ADH
which hormone’s synthesis can be blocked by alcohol or coffee?
ADH
def: process where large particles remain in circulatory system, only small particles go through and form the filtrate, which is pushed into Bowmann’s capsule
filtration
def: process where glucose is completely reabsorbed, after passing through the components of the nephron, molecules and ions are pulled back into blood from kidney
reabsorption
def: substances are removed and secreted from the blood through peritubular capillaries into the nephron
secretion
def: urine physically leaves the body
excretion
def: a capillary network that interacts with Bowmann’s capusle
glomerulus
def: a structure that surrounds glomerulus
bowman’s capsule
def: cells in bowman’s capsule that filter blood
podocytes
def: portion between Bowman’s capsule and the loop of Henle, substances are reabsorbed from the filtrate back into the blood, most reabsorption occurs here
proximal convoluted tubule
def: permeable to only water, water leaves the kidney tubules, which increases the solute concentration in the tube
descending loop of Henle
