The urinary system Flashcards
may contain about _____ of body’s blood
25%
3 main parts of kidney
1) renal cortex = outer layer of connective tissues
2)renal medulla inner layer
3) renal pelvis = hollow chamber that joins kidney with ureter (tubes that connect the kidneys to bladder)
Each nephron is surrounded by a network of _________
closest connection to the circulatory system is at the ________
which surrounds a cluster of capillaries called the _________
Fluids to be processed into urine then diffuse from the ________ into the Bowman’s capsule and then move through the tubule to be _________
Capillaries
Bowman’s capsule
glomerulus
glomerulus
3 functions of kidney
filtration
selective reabsorptions
secretion
Filtration
movement of fluids from blood into Bowman’s capsule
how filtration occurs
blood pressure from heart at glomerulus drives filtration, the pressure filterst the blood by forcing water and solutes out from the glomerular capillaries into the bowmans capsule which is
Permeable to H2O, NaCl, gluecose, amino acids, H+, urea
Impermeable to plasma proteins, blood cells, platelets (these are all too big)
what generates blood pressure during filtration
the heart beat that drives filtration at glomerulus
how does filtering occur in filtration,
the pressure created from the heart beat filters the blood by forcing water and solutes out from the glomerular capillaries into the Bowman’s capsule which is;
Permeable to H 2 O, NaCl, glucose, amino acids, H + , urea
Impermeable to plasma proteins, blood cells, platelets (these are
too big)
what is filtration permeable to
what is filtration impermeable to
H2O, NaCl, glucose, amino acids, H+ urea
plasma proteins, blood cells, platelets
Selective reabsorption
about ___ ml of fluid flows through the kidneys every _____ and _____ ml of that is filtered into the ________
Luckily ________ is reabsorbed so that you wont produce 120 ml of urine a minute, therefore you only produce ___ ml of urine
what two molecules are reabsorbed back into blood stream during selective reabsorption and what molecule does this
Reabsorption occurs until ?
600
120
nephrons
119ml
1ml
glucose and amino acids and this is done by a specific carrier molecule
Reabsorption occurs until threshold levels are reached
true or false
solutes which are transported out of the nephron also draw water from the nephron
true
- Secretion
substances secreted may be….\
where does the majority of secretion occur
the fluid arriving in the distal tube is ? c or d
how does the distal tubes structure provide energy for active transport
nitrogenous wastes (NH 3 , urea), excess H + , minerals such as K+, and drugs
distal tube
dilute but can be concentrated if the need arrives
cells lining the distal tubule are loaded with mitochondria to provide energy
for active transport
arterioles delivering the blood to the glomerulus have a _________ and less resistance to flow than the ____________
the blood dams up in the glomerulus, increasing the pressure for ______
wider diameter
vessels carrying blood away
filtration
Bladder capacity:
when the bladder contains 200 ml of urine, what happens
when the bladder reaches 400ml what happens
when the bladder reaches 600ml what happens
Bladder capacity:
when the bladder contains 200 mL of urine, it stretches and sends a signal to the brain (“I have to pee!!”)
when the bladder reaches 400 mL, more stretch receptors are
activated and message becomes more urgent (“I really have to pee!!”)
If ignored, once bladder reaches 600 mL, the urinary sphincter relaxes,
and urine is dumped into the urethra and is expunged (“Uh oh…”)
what transports glucose and amino acids back into blood stream
a specific carrier molecules
where does secretion happen the most?
distal tube
