Download The Excretory System

How Our Body Eliminates Cellular
Wastes
Excretion
When proteins are broken down into amino
acids, during digestion, they travel to the
liver to be stored.
Excess amino acids are converted to glucose,
glycogen, or fat.
This conversion produces a toxic substance
called ammonia, which when combined
with CO2, forms urea.
Although Urea is safe to travel in the blood
stream, it still needs to be expelled from
the body (a build up of urea in the body can
be toxic).
Excretion
It is the role of the excretory system
to remove urea and other waste
products, such as; water and CO2
(products of cellular respiration).
The removal of waste products from
the body is referred to as
EXCRETION.
Excretory System – removes
excess water, H2O, urea,
carbon dioxide, CO2, and other
wastes from our blood.
Kidneys – filter out excess water
and urea
Lungs – filter out carbon dioxide,
CO2, from the blood.
Skin – excretes water, as sweat,
which contains some trace
chemical wastes, including
urea.
Vein to heart
Artery from heart
Kidney
Kidney
Renal Artery
Renal vein
Ureters
Bladder
Urethra
Kidneys – filter wastes and
excess water from the
blood.
Ureters – tubes that take
urine from the kidney to
the urinary bladder.
Urinary Bladder – a sack that
stores urine.
Urethra – small tube that
leads urine out of the
body.
I. The Kidneys
Every drop of blood in your
body is filtered by your
kidneys more than 300
times per day!
Kidneys eliminate urea,
minerals and excess water.
Kidneys regulate the amount
of water we need to
maintain in our bodies.