How the kidneys work

What are the roles of the kidney?

1. To remove waste products

2. To regulate water and ion levels

how is urea made?

Urea is made in the liver via deamination (excess amino acids are converted to fats and carbs)

What does the liver regulate?

Water & ion levels

How is water lost?

1. Sweating

2. In breath

3. Urine

What happens when water levels are unregulated

1. Cells may swell and burst due to lack of cell wall (too much)

2. Cells may shrink and shrivel (too little)

Explain the what happens to the blood in the kidneys

1. Filtration: small molecules are absorbed (water, glucose, amino acids, urea) but large molecules are not

2. Selective reabsorption: molecules that we need are reabsorbed (all glucose, some water)

How is water regulated in the body

Too Low Too High

1. The hypothalamus detects the concentration of water in the bloodstream.

2. A signal is sent to the pituitary gland/Signals to the pituitary gland are stopped

3. ADH is released/ADH release is stopped

4. More water is reabsorbed/Less water is reabsorbed

5. Less urine/More urine

the process of osmoregulation is a _____ _____ ____

Negative feedback loop

How does blood enter and exit the kidneys?

It enters via the renal arteries and exits via the renal veins

What happens to urine after the kidneys?

It travels to the bladder via the ureters until it is urinated out via the urethra

What are the filtering structures in the kidney called?

Nephrons

What are nephrons made of?

Tubules that carry filtered fluid that becomes urine

Blood vessels that carry blood

What is a glomerulus

A tangle of blood vessels at the entrance of the nephron

What is the bowman/s capsule?

The start of the tubule, where filtered materials go

What happens in the nephron after the Glomerulus and Bowman’s capsule?

Selective reabsorption of filtered materials:

Almost all glucose and amino acids, some water and ions, no urea