Excretory System
By: Jessy Gonzalez, Alexis Segura, Gaby Guzman
Mrs. .Jolly 4rth period Science Class
The Excretory System is …
 The excretory system is the system of an organism's
body that performs the function of excretion, the
bodily process of discharging wastes.
 The Excretory system is responsible for the
elimination of wastes
 The major function parts of the system are lungs,
kidneys , urinary bladder, urethra, ureter, liver ,and
skin
Diagrams of Major Parts of
Excretory System
Kidneys, Bladder (Urinary
bladder),Urethra, Ureter Function
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Kidneys: The kidneys are two bean shaped organs, each about the size of a fist .They are
located just below the rib cage on each side of the spine. Every day, the two kidneys filter
about 120 to 150 quarts of blood to produce about 1 to 2 quarts of urine, composed of waste
and extra fluid.
Urinary Bladder: The bladder, like the stomach, is an expandable sack that contracts with
inner folds when it is empty. The inner lining of the bladder tucks into the folds and expand
out to accommodate liquid. Which is urine so in other words it is a sack that holds urine until
it is time to go to the restroom. When empty, the bladder’s muscle wall becomes thicker,
and the entire bladder becomes firm.
Urethra: The urethra is a tube that connects the urinary bladder to the outside of your body
and this works as an exit from the you body.
Ureter: The ureter is the tube that carries urine from the kidney to the urinary bladder. In
humans there are two ureters one attached to each kidney and the upper half. It is located in
the abdomen and the lower half is located in the pelvic area. Each ureter enters the bladder
through a tunnel in the bladder wall, which is angled to prevent the urine from running back
into the ureter when the bladder contracts.
Skin Function
 Skin is a part of the Excretory system sweat is a crucial part
of the excretory system as it is responsible for eliminating
sweat from the body. Salt contains several metabolic
wastes including urea, salts and water. In addition to
excreting metabolic wastes, sweat also cools down the
body. The sweat glands are able to receive the various
wastes because they are mixed in with capillaries, which
are tiny blood vessels. This means that the wastes can
diffuse out of the blood and enter the sweat glands before
passing out of the skin in the form of sweat.
Liver Function
 The liver is also a part of the Excretory system.
 What it does: That the liver produces proteins that
are important in blood clothing. It is also one of the
organs that break down old or damaged blood cells.
The liver is responsible for detoxifying and breaking
down any toxins such as chemicals and poisons that
enter our bodies. The liver produces bile which the
body then uses to help break fats down into unusable
waste and usable fats.
Lung Function
 Last of all are the lung’s function in the Excretory
system. As human beings we need cellular respiration
to survive or we would die. Cellular respiration
produces carbon dioxide and that needs to be
eliminated out of our body. When the carbon dioxide
diffuse from the cells entering the bloodstream then
for it going to the lungs. The lungs have alveoli which
diffuse the carbon dioxide from the blood so it can
enter the lung tissue and eventually leave the body
during exhalation.
Fun Facts
 The average person pees about 3000 times a year
 The average person poops about 305 pound of poop a
year
 The human intestine is about 27 inches long and about 10
inches
 The average adult bladder can hold 16 to 24 ounces of
urine
 If you compare the human brain with the human bladder it
is about the similar size and weight
 The biggest vein in the body is the vein that leads it the
vital excretory system, the kidney