Excretion Flashcards
What waste do the kidneys remove?
Urea, water and mineral ions
What waste do the lungs remove?
Carbon dioxide and water
What waste does the skin remove?
Mineral ions and water
What does urine contain?
Water, urea and ions
What does the glomerular filtrate compose of?
Small molecules e.g. glucose, urea but not blood cells and large molecules e.g. proteins
How does the kidney carry out its role of excretion?
By removing waste products from the blood e.g. urea
How does the kidney carry out its role of osmoregulation?
By removing excess water and excess salts
Where does the selective reabsorption of glucose take place and why?
The proximal convoluted tubule because the cells have more mitochondria for active transport
How does ADH work?
When osmoreceptors in the hypothalamus detect the blood is too concentrated, they stimulate the pituitary to release ADH allowing more water to pass from the collecting duct back into the blood around the Loop of Henle by causing more water channels (aquaporins) to appear in the wall of the collecting duct.
