Homeostatis And Excretion Flashcards
What do kidneys do
They filter the blood and controls the amount of ions and water being absorbed into the blood
What’s negative feedback
Keeps conditions constant inside body
Specifically what do the kidneys do and how do they do it
- Removes urea from blood
- Adjusts salt levels in blood
- Adjusts water levels in the blood
They do this by filtering stuff at high pressure and reabsorbing the useful things
Describe ultrafiltration
- Blood from renal artery flows through glomerulus
- High pressure squeezes water, urea, salts and glucose out of blood and into the Bowman’s capsule- this is know as the glomerular filtrate
Describe reabsorption
- All glucose is reabsorbed into the blood from the promise convicted tubule(active transport)
- Sufficient salts are reabsorbed
- Sufficient water is reabsorbed from the collecting duct ( selective reabsorption)
Describe the release of wastes
Remaining substances (water,urea, salt) form urine and go through the ureter, stored in the bladder and released via the urethra
What is osmoregluation
The body balancing the water going in and the water going out and does this by adjusting the amount of water excreted by the kidneys
How does ADH help osmoregluation
It makes nephrons more permeable so more water is reabsorbed into the blood
Describe osmoregluation with water gain
- Brain detects water gain
- Pituitary gland releases less ADH
- Kidneys reabsorb less water
- Hydrated
Describe osmoregluation with water loss
- Brain detects water loss
- Pituitary gland releases more ADH
- Kidneys reabsorb more water
- Hydrated
How is water lost through organs
Through lungs, kidneys and skin