The Kidney Flashcards
Name the structure that delivers blood INTO the kidney?
The renal artery
Name the structure that delivers blood OUT OF the kidney
The renal vein
Blood from the renal artery enters _____________
Blood from the renal artery enters _ smaller arterioles in the cortex of the kidney
The _____ ______ takes blood into the glomerulus
The afférent artériole takes blood into the glomerulus
What is the glomerulus?
A bundle of capillaries looped inside the Bowman’s capsule
Ultrafiltration is also known as?
Glomerular filtration
The blood is under high pressure which causes ultrafiltration. Why is the blood under high pressure?
1) Pumped from aorta, high pressure as has to get around whole body
2) The afférent artériole is WIDER than the efferent artériole. This acts like when a lane is closed on the motorway.
State the three layers in glomerular filtration
1) Capillary fenestrations
2) Basement membrane
3) Bowman’s capsule epithelium (containing podocytes)
Describe capillary fenestrations in ultrafiltration
They contain large gaps which allow blood plasma through but not large objects like proteins and erythrocytes (red blood cells) through
Describe the basement membrane in ultrafiltration
It supports the cells of the capillary endothelium; acting as a fine filter allowing small plasma proteins through.
(The maximum size that can pass through is called the renal threshold and is a molecular mass of 68,000)
Describe the Bowman’s capsule epithelium (and podocytes) in ultrafiltration
The form the lining of the renal capsule and have large gaps between them which allow the glomerular filtrate through into the renal space
The outer section of the kidney is called?
The cortex
The inner section of the kidney is called?
The medulla
Selective réabsorption occurs along the…
PCT
Loop of Henle
DCT
PCT =
Proximal convoluted tubule
DCT =
Distal convoluted tubule
State two adaptations of the PCT cells to enable selective reabsorption
1) High numbers of microvilli —> Increases the sa:vol ratio for the reabsorption of useful materials from the glomerular filtrate into the blood
2) High numbers of mitochondria —> More ATP able to be produced to power the active transport of substances
Urine usually contains: (3 points)
1) Water & dissolved salts
2) Urea
3) Other substances such as hormones and excess vitamins
Urine doesn’t usually contain: (2 points)
1) Proteins and blood cells –> they’re too big to be filtered out of the blood
2) Glucose, as its actively reabsorbed back into the blood
The regulation of the blood’s water potential is called…
Osmoregulation
When the water potential of the blood is too low…
1) More water is reabsorbed by osmosis into the blood from the nephron tubules
2) Urine is ore concentrated, less water is lost
When the water potential of the blood is too high…
1) Less water is reabsorbed by osmosis into the blood from the nephron tubules
2) Urine is less concentrated, more water is lost
Blood ADH level _____ when you’re dehydrated
Rises when you’re dehydrated
BLood ADH level _____ when you’re hydrated
Lowers when you’re dehydrated