Excretion and the Kidneys
What is excretion?
Excretion:
Metabolism:
One type of waste is not excreted:
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It is necessary for the body to rid itself of waste products
It is also important to regulate the volume and composition of body fluids
The excretory systems of the body do this.
Where does excretion occur?
Nitrogen waste (urea):
Excess water:
Carbon dioxide:
Excess salt:
Why is it important to remove excess water and salts?
Water and salt content in the blood and body must be kept constant.
Too much water =
Too much salt =
The kidneys
What the kidneys do:
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The kidney removes _____________from our _____________
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It also adjusts the amount of __________ and ______________ in the _____________
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The kidney sends the wastes to your _______________to be _________________ as
__________.
What is urine?
Anatomy of the kidney:
How the kidneys work
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Blood arrives from the _______________ ________________ and enters a ball of capillaries
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Small molecules leave the capillary and enter the Bowman’s capsule by _________________.
These include ________________________________________________________________.
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The filtered blood moves down the nephron (inside the kidney)
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In the convoluted tubule, cells ___________________ useful substances:
_____________________________________________________________
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The rest (___________________________) moves on through the nephron
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This is called __________________________________________________
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The water and urea are now called _____________
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As the urine moves on, more _________________ is saved in the loop of Henle and
collecting duct and returned to the blood.
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This adjusts the water loss to suit the level of water in the body.