2i - excretion Flashcards
what is the difference between egestion and excretion?
excretion is the removal of waste produced by the body’s metabolic reactions. egestion is the removal of undigested material from the body
what is urea and where is it removed through?
urea is the chemical that comes out the cells, it is removed through the kidneys
where is CO2 from and where is it removed through?
CO2 comes from respiration and is removed through the lungs
what is a nephron?
microscopic kidney tubule where ultrafiltration and reabsorption take place to produce urine
how many nephrons does each kidney contain?
approximately a million nephrons.
what is ultrafiltration?
any molecules which are small are filtered out the blood and into the bowman’s capsule due to the pressure
what is the water sitting in the bowmans capsule called?
glomerular filtrate
where does ultrafiltration occur?
the bowmans capsule
where does the blood travel through in the nephron?
it comes in through an arteriole, to the glomerulus and the bowmans capsule, it then travels to the proximal convoluted tubule through to the loop of henle. after this it travels to the distal convoluted tubule into the collecting duct.
where does the reabsorption of water occur?
in the collecting duct
where does the selective reabsorption of glucose occur?
in the collecting duct
what is the main organ of excretion in plants?
the stomata, it releases CO2 in respiration.
what does the renal artery do?
supply the kidneys with blood
what does the renal vein do?
the blood leaves through the renal vein
what does the ureter do?
urine flows down this into the bladder
what does the bladder do?
it stores urine
what does the urethra do?
this is where after the urine flows out the bladder it flows through here
what does the ring of muscle do?
prevents the bladder from leaking
what does the kidney do?
it filters blood to remove waste substances
what is reabsorbed in selective reabsorption?
all the glucose and some of the sodium ions.
what is homeostasis?
homeostasis is the regulation of internal body conditions e.g. temperature, blood glucose and ph levels
what ware ureters?
tubes that connect the kidneys to the bladder
what is the hypothalamus?
the part of the brain that monitors water content of the blood, and is where ADH is produced
