1. Using your notes, explain how the different systems work together daily.

2. Cells and Systems Excretory System
ONACD –Editable Curriculum designed for teachers by teachers

3. The process of removing excess water, salts and wastes from the body
What is Excretion?
The process of removing excess water,
salts and wastes from the body
But didn’t we get rid of waste through the respiratory system (CO2) and the digestive system (solid waste left after food is digested)?
Yes…. But what about the chemical waste that comes from our cells and is carried around in our blood stream?

4. The Kidney Label the diagram to the left
All blood cells must eventually
travel through the KIDNEY
which is the major organ used
in excretion.
Label the diagram to the left
with the following terms:
Urethra, ureters, bladder, kidneys
Kidneys
Ureters
Bladder
Urethra

5. A peek into the inside of the bladder!
The kidney filters the blood for wastes. As
the blood moves across the kidney, specifically
each individual nephron, the pressure is very
high.
Waste (salt, urea (formed by the liver), excess
glucose) dissolved in water moves across
the thin walls of the blood vessels into the
nephron.
Some of the water and salt is put back into the blood stream but all the excess is transported through the kidney and sent through the ureters to the bladder to be held until it is to be eliminated through the urethra.
Left:
A peek into the inside of the bladder!

6. Random Excretory Facts
Each blood cell passes through the kidneys 300 times a day.
The nephrons clean all your blood every 45 minutes. 
Every day the nephrons send about six cups of urine to the bladder.
In some people urine develops an unusual smell soon after eating asparagus. The smell is due to a chemical called methyl mercaptain.