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Question 1

what is a nephron

Answer 1

each kidney over 1 million filtering units called nephrons made of a tuble and are responsible for cleaning the blood by removing urea excess water and mineral ions

Question 2

what are the stages the kidney works in

Answer 2

1. filtration. blood passes into the network of capillaries called glomerulus which runs inside the Bowmans capsule of each nephron. getting rid of what is not needed like urea excess water and mineral ions.
2. selective reabsorption. the body takes back in useful substances it needs. this includes glucose and some mineral ions. theese substances are pumped through protiens in the cell membranes in the first convoluted tube of the nephron by active transport. no glucose is left in the urine.
3. water is reabsorbed by osmosis, depending on how much the body needs. this happens in the loop of henle and in the collecting duct.
4. formation of urine at the end of the nephron the remaining fluid flows into the ureter. the fluid contains excess water that the body does not need, plus urea and other substances. it is called urine