ANSC 512 Urinary System - Kidney and Glomerular Filtration

2 kidneys, 2 ureters, urainry bladder, urethra

What does the urinary system consist of?

metabolic waste (useless substance produced by body), nitrogenous waste (toxic, 50% urea, uric acid, creatinine)

What is a waste product?

blood urea nitrogen - measures how well kindeys are functioning (too high = lower function)

What is BUN?

A WET BED

What is the acronym for functions of the kidney?

A - acid-base balance

W - water balance

E - electrolyte balance

T - toxin removal

B - blood pressure control

E - makes erythropoetin

D - vitamin D metabolism

What does A WET BED stand for?

arcuate vessels

What is structure 1?

minor calyx

What is structure 2?

major calyx

What is structure 3?

renal pelvis

What is structure 4?

renal pyramid

What is structure 5?

renal papilla

What is structure 6?

renal column

What is structure 7?

renal cortex

What is structure 8?

renal capsule

What is structure 9?

ureter

What is structure 10?

renal medulla

What is structure 11?

renal artery

What is structure 12?

renal hilum

What is structure 13?

renal nerve

What is structure 14?

renal vein

What is structure 15?

interlobar vessels

What is structure 16?

cortical vessels

What is structure 17?

nephron

What is the fuctional unit of the kidney?

renal cortex and medulla

Where are nephrons found?

system of tubes associated with system of blood vessels

What are nephrons?

renal corpuscle

What is structure 1?

proximal convoluted tube

What is structure 2?

glomerulus

What is structure 3?

efferent arteriole

What is structure 4?

afferent arteriole

What is structure 5?

Bowman's capsule

What is structure 6?

glomerulus, proximal convluted tubule, nephron loop, distal convoluted tubule, collecting duct

What is the flow of fluid through the nephron?

hydrostatic pressure (fluid on walls of tube) and colloid oncotic pressure (proteins in blood)

What are the two pressures at play with glomerular filtration?

if there is more fluid, there is going to be a higher pressure gradient, pushing more material through the membrane (always greater inside than outside)

How does hydrostatic pressure impact glomerular filtration?

proteins cannot move across membrane so they exert great force on the venule side making the pressure greater in the blood than the tissues

How does colloid oncotic pressure impact glomerular filtration?

the use of ATP to move material against a concentration gradient via enzymes, carriers, pumps

What is active transport?

movement reliant on concentration gradients (always high to low)

What is passive transport?

fenestrated endothelium of arteriole, basement membrane with (-) glycocalyx gel, filtration slits between foot processes of podocytes, and then urinary space

What layers must fluid move through from blood to filtrate in the glomerulus?

can: water, electrolytes, small positive ions, nitrogenous waste

cannot: proteins, vitamins, negatively charged dissolved particles, blood cells

What can move into urinary space and what cannot?

rate at which the glomerulus filters blood

What is the glomerular filtration rate?

blood and capsular fluid pressure, hydrostatic pressure

What impacts glomerular filtration rate?

no - proteins cannot move across barrier into tubule

Is there colloid oncotic pressure in the glomerulus?

high hydrostatic pressure in afferent arteriole

What drives fluid into the tubule?

too much filtration occurs which can result in dehydration and electrolute depletion

What happens if the GFR is too high?

too much reabsorption happens and toxic material stays in body

What happens if the GFR is too low?

sympathetic control, renal autoregulation, hormonal control (epinephrine)

How is the GFR controlled?