Kidneys (osmoregulation) Flashcards
where does osmoregulation take place?
In the nephrons of the Kidney
What is the first stage of osmoregulation?
Deamination through the Ornithine cycle.
Where does deamination happen?
The liver
What happens in deamination?
Excess amino acids converted into urea by removing the amine group from ammonia
Where does ultrafiltration take place?
In the malpighian body (Glomerulus + Bowman’s capsule)
How are small molecules forced out of the glomurulus into the Bowman’s capsule?
There is a high blood pressure caused by the afferent arteriole (entering) being wider than the efferent arteriole (leaving)
What takes place in the PCT?
Selective reabsorption
Why does reabsorption need to take place?
Many necessary substances are required in the blood so they need to be reabsorbed
What is actively transported back into the blood?
~Glucose
~Amino acids
~proteins
~Vitamins
~Hormones
What does water and other ions do?
Osmosis and diffusion down the concentration gradient.
What adaptations does the Loop of Henle have to concentrate urine?
Blood and filtrate run in a countercurrent multiplyer.
What happens in the descending limb of the loop?
It’s permeable to water so water moves into the medulla by osmosis down the water potential gradient
What happens in the ascending limb of the loop?
Permeable to ions, impermeable to water so ions move out by diffusion in lower, thinner part and active transport in the higher thicker part.
What is role of the ascending limb?
To maintain the water potential gradient in the medulla to ensure water always moves out of the descending limb by osmosis.
