Kidneys overwiew

Question 1

What is the role of the kidneys?

Answer 1

• The kidneys are in charge of filtering the blood to remove waste products (urea) and regulate the amount of useful things (ions and water)

Question 2

What is deamination?

Answer 2

• The process by which urea is produced in the liver
• Excess amino acids form fats and carbohydrates for storage and urea as a waste product

Question 3

Why is water regulation important

Answer 3

• Too much water: water diffuses into cells via osmosis causing them to swell and possibly burst
• Too little water: water diffuses out of cells via osmosis causing them to shrink

Question 4

What ways is water lost from the body

Answer 4

• Sweat
• Lungs when breathing
• Urine

Question 5

What is a nephron?

Answer 5

• Inside both kidneys, there are millions of structures known as nephrons
• Each nephrone contains a blood capillary intertwined with a tubule

Question 6

How do nephrons work?

Answer 6

• Blood passes through blood capillaries and anything small is absorbed by the tubules (water, glucose, urea and ions but NOT cells and proteins)
• Selective reabsorption: important things are reabsorbed back into the bloodstream (all glucose, some water and no urea)

Question 7

How does water regulation work?

Answer 7

• Hypothalamus detects change in water conc
• If water concentration is low: hypothalamus sends signals to pituitary gland which stimulate it to release ADH. ADH tells blood in kidneys to reabsorb more water from tubules
• If water concentraction is high: hypothalamus stops sending signal to pituitary gland so it stops releasing ADH. Therefore, less water is reabsorbed in kidneys