urinary system

osmolarity

water/salt ratio

blood osmolarity balance

monitor electrolyte/ions and H2O balance: + hormones ADH

waste excretion

urea → via deamination of amino acids (remove nitrogen)

PH regulation

via H+ ion secretion & reabsorb of HCO3- (bicarbonate)

blood pressure regulate

renin, angiotensin II, aldosterone (Na+) → blood volume

erythropoietin

(EPO) secretion to make RBCs → red marrow

H+

proton = acid

reabsorb

take from urine back to blood

secretion

from blood into kidney tubes/urine

location

retroperitoneal space, has capsule of adipose (fat) & adrenals on top (superior)

hilum

depression where vessels enter/exit

regions

cortex & medulla containing parts of nephrons and pyramids

nephrons

filtering units

pyramids

concentrate urine

calyx

cup regions, collect urine from pyramids

renal pelvis

funnel, forms superior ureters

ureters

empty into bladder

bladder

muscle, stores urine, anterior to uterus & anterior to rectum, male prostate gland = inferior

epithelial

lines organs

detrusor (smooth muscle)

aids micturition/voiding

trigone muscle

triangle, acts as valve, aids continence

continence

ability to hold and use

internal sphincters (relaxing fills urethra)

circular muscle: regulate release of urine to urethra involuntarily (autonomic)

external sphincter

skeletal/somatic muscle, control → micturition from urethral meatus

meatus

opening to a tube/canal

micturition

to pee

urethra transports…

urine out of body

mucosa

trap stuff

men have

one opening, urethra passes through prostate, serves as a semen transport

afferent

into a location

efferent

away/exit

renal artery

afferent arteriole → feeds glomerulus

nephron glomerulus (capillaries)

HI hydrostatic pressure & gradients, filter out substances thru capillary fenestrations into Bowman’s Capsule

filtrate

liquid to become wee & includes: H2O, glucose, urea, H+, electrolyte/ions. RBCs and proteins not filtered

efferent arteriole

drains blood to renal vein → vena cava

peritubular capillaries & vasa recta

vessels is @ nephrons to reabsorb H2O & nutrients & secrete wastes into nephron that will become pee

vasa recta

caps @ loop henle

osmotic/colloidal pressure (solutes) in Bowman’s law is low

hydrostatic is driving force to make filtrate

125 mL/min filtrate made

180L / day

99% of filtrate reabsorbed by…

nephron under influence of gradients, hormones, etc.

uresis =

urinate

1-2 L

urine output/day

albumin is like a…

osmotic sponge that absorbs water

if albumin escapes into Bowman’s via inflammation…

increases osmotic pressure (solutes/salt) in Bowman’s and nephron

over time, systemically, there is…

lower osmotic pressure in blood and more H2O (hypotonic)

edema (swelling)

H2O diffuses thru capillaries into tissues

passive/simple diffusion

no ATP, things move down gradient HI - Lo concentration

facilitated

still passive but uses carrier protein to move glucose b/c of size

active transport

shows antiport, ions moving in opposite directions using ATP

Secondary active transport

shows symport as 2 molecules diffuse together, using a transport protein and gradient

power in electromechanical [Na+] gradients as…

it flows Hi-Lo, draws things with it, not all movement needs ATP

Proximal convoluted tube (PCT)

majority of reabsorption HERE!

Apical cell side

faces nephron lumen & filtrate      

basal

faces interstitial/ tissue

Filtrate passes into PCT, most active reabsorb area of :

Na+, electrolytes, H2O, glucose

Na+ symport: apical side:

transports glucose out of nephron filtrate → glucose then diffuses into peritubular capillary

NA/K ATP pump (active trans)

pumps 3 Na+ into interstitial & then Na+ diffuses into peritubular caps… H2O will diffuse Hi-Lo gradient b/c of this

Na+/H+ antiport

secrete H+ into filtrate = acidic (Low pH) wee + Na+ adds to gradient for H2O to follow

HCO3- (bicarbonate)

important for pH balance, is symported with Na+ ions = buffer blood

ions: Cl-, Mg, Ca2+…

use symport proteins from filtrate

loop of henle

reabsorb Na+ & H2O into vasa recta capillaries

as H2O lost in loop of Henle…

osmolarity increases down in loop (increased concentration)

Ascending loop

thick portion impermeable to H2O, BUT Na+ actively transported (Na/K+ ATP pump) into interstitial space @ loop

hyperosmotic

lots of solutes/salt

ascending is vital b/c…

it forms hyperosmotic gradient so H2O can diffuse out of descending loop

countercurrent

against

THIS = COUNTERCURRENT EXCHANGE

H2O diffuse out as we move down, Na+ is transported out as we move up

urea (nitrogen waste)

byproduct of the breakdown of Amine (NH2) group of amino acids via liver

urea diffuses into…

descend loop lumen

When H2O leaves

more concentrated (more salt than water) higher number

When salt leaves

less concentrated (more water than salt) lower number

calyx (pic)

renal pyramids (pic)

renal medulla (pic)

renal cortex (pic)

renal capsule (pic)

hilum (pic)

renal pelvis (pic)