Ultrafiltration and SR Flashcards
Where does ultrafiltration occur?
In the renal capsule of the renal corpuscle
What is the blood pressure in glomerular capillaries?
High
Why is there high blood pressure in glomerular capillaries?
Afferent arteriole is wider than efferent arteriole
What is ultrafiltration?
Pressure forces plasma out the blood so only blood cells and large plasma proteins remain
What is GFR?
The glomerular filtration rate - rate of filtrate production
What affects GFR?
Hormones and blood pressure
What is the hydrostatic pressure of the blood?
Higher as efferent arteriole has a smaller diameter
What is the hydrostatic pressure of glomerular pressure?
Lower as filtrate can flow onwards to rest of nephron
What is the water potential of blood?
Lower as water loss and retention of large plasma protein
What is the water potential of glomerular filtrate?
Higher as gained water
What is the net movement of blood?
Loss of water and solutes
What is he net movement of glomerular filtrate?
Gain of water and solutes
What is the direction of filtration?
From blood into capsule
What supports capillary endothelial cells?
Renal capsule epithelium podocytes
What do podocytes do?
Leave slits for filtrate to pass into capsule
What does glomerular filtrate contain?
Water, urea, salts, glucose and amino acids
What barrier must filtrate cross?
3 stage barrier
3 stage barrier
