Biology 3 - The Human Kidney.
- Kidneys are one of the main organs which maintain homeostasis (keep internal conditions as constant as possible)
- They are involved in excretion (removing waste)
- kidneys filter urea out of the blood, temporarily stored in the bladder
Balancing Water in the body
- You gain water when you eat or drink, water is constantly lost from the lungs.
- The water evaporates into the air in your lungs and is breathed out.
- When you exercise you get hot and sweat more which means you lose more water
- If you are short of water, the kidneys conserve it.
- You produce very little urine (more anti diuretic hormone produced) and most of the water is saved for use in your body,
- Drinking too much water means that the kidneys produce lots of urine to get rid of the excess.
- Ion concentration is also balanced by the kidneys, they remove excess mineral ions (particular sodium and chloride ions from salt)
- You take in a lot of mineral ions if you eat alot of salt…