The kidney Biology unit 3
- Created by: carylmilena
- Created on: 21-04-18 10:42
View mindmap
- The Kidney
- Ultrafiltration
- Filtration under pressure
- Glomerular filtration rate= the rate at which fluid passes from blood to glomerular capillaries into Bowmans capsule
- Separates small soluble molecules from the blood plasma in Bowmans Capsule
- lies between blood and nephron and filters solutes
- Selective reabsorption
- Useful products are reabsorbed (GLUCOSE, WATER, SALTS) in the proximal convoluted tubule.
- Remaining WATER taken in by collecting duct
- Basement membrane of capillary is a selective barrier
- Hydrostatic Pressure forces molecules through filter, amplified by the narrowness
- Structure
- URETER carries urine from kidney to bladder
- Serves proximal and distal convoluted tubules
- Blood recieved by renal artery and sent to renal vein
- Afferent arteriole- >glomerulus->capilaries
- Vasa recta along loop of henle
- nephrons have close association with blood vessels
- ADH
- Decreased ADH makes walls less permeable to absorb less water
- Affects permeability of collecting ducts and distal convoluted tubules
- Increased ADH makes wallks more permeable ro reabsorb more water
- Homeostasis
- Maintenance of a constant environment
- receptor detects deviation
- set point is desired norm
- After correction detector turns off
- Coordinator communicate with effector to correct deviation
- Excretory products
- Mammals excrete urea, less toxic than ammonia = can be stored for short time= needs energy
- Birds and insects excrete uric acid, insoluble, needs high energy but little water, useful when water is scarce
- Fish produce ammonia, highly soluble so diffuse out across gills and dilute to non-toxic levels
- Loop of henle
- loop is most concentrated at the bottom
- Counter current multiplier
- Collecting duct fluid runs back down the medulla through the low water potential causing more water to pass out into the vasa recta
- Maximum concentration is built up inside and outside the apex of the loop
- Counter current multiplier
- Collecting duct fluid runs back down the medulla through the low water potential causing more water to pass out into the vasa recta
- High concentration of salts in medulla causes osmotic flow of water out of ducts concentrating urine so hypertonic to blood
- Counter current multiplier
- Counter current multiplier
- Ascending limb walls impermeable to water actively transporting Na+ and Cl- out into tissue fluid between the 2 limbs to lower the water potential
- Fluid flows down and water passes out by osmosis while Na+ and Cl+ diffuse in losing lots of water
- loop is most concentrated at the bottom
- Osmoreceptor= detect changes in solute concentration in blood to regulate osmoregulation on a negative feedback principle.
- Desert Mammals
- Live on metabolic water produced from oxidising food reserves
- Longer loops of henle for greater water potential gradient
- Live undeground as cooler = reduce water loss by evaporation
- reabsorb more water
- RECAP
- Decreased conc
- Hypothalmus
- Increased conc
- Pituitary Gland
- Decreased conc
- Hypothalmus
- Increased conc
- Pituitary Gland
- ADH
- More ADH
- Less ADH
- Wall of collecting duct
- Less ADH
- More ADH
- More permeable
- ADH effect
- decreased
- concentration of urine
- Increased
- volume of urine
- normal
- volume of urine
- decreased
- volume of urine
- normal
- volume of urine
- Increased
- concentration of urine
- increased
- concentration of urine
- Increased
- decreased
- Increased
- concentration of urine
- decreased
- ADH effect
- Less permeable
- ADH effect
- decreased
- increased
- decreased
- ADH effect
- ADH
- Hypothalmus
- ADH
- Wall of collecting duct
- More permeable
- Less permeable
- More permeable
- Wall of collecting duct
- Decreased conc
- Hypothalmus
- Decreased conc
- Ultrafiltration
Similar Biology resources:
Teacher recommended
Comments
No comments have yet been made