The kidneys Flashcards
What is the role of the kidneys?
Kidneys filter the blood to remove waste products and also regulate the water and salt content in the body.
What are the substances removed from the body in urine?
Urea, ions and water.
What is deamination?
Where excess amino acids are converted to fats and carbohydrates for storage.
What is a waste product of deamination?
Ammonia and it is toxic so is converted to urea in the liver. Urea is then transported to the kidneys, filtered and excreted in urine.
What do the kidneys contain?
Nephrons that contain a tubule that absorbs anything small like water, glucose, amino acids and urea.
What can’t the nephrons absorb?
Cells and proteins.
What is reabsorbed by selective reabsorption?
Glucose, some ions and some water.
What other ways are water and ions removed from the body?
Both are also removed in sweat and water is also lost by breathing.
What happens if there is too much water in your body?
Your body will cause the water to diffuse into your cells by osmosis causing the cells to swell or burst.
What happens if there is too little water in your body?
Your cells could lose their water and shrink.
What hormone is the concentration of water controlled by?
ADH which is released into the bloodstream by the pituitary gland.
What happens if the water content is too high?
1) A receptor in the brain detects the water content is too high.
2) The coordination centre in the brain receives the information and coordinates a response.
3) Pituitary gland releases less ADH so less water is reabsorbed.
What happens if the water content is too low?
1) A receptor in the brain detects the water content is too low.
2) The coordination centre in the brain receives the information and coordinates a response.
3) Pituitary gland releases more ADH so more water is reabsorbed.
