Transcript Excretory System

Excretory System
Any system that eliminates wastes
Included in excretory system are:
• Digestive-water and
undigested food out
• Respiratory- carbon
dioxide and water out
• Skin (Integumentary)sweat and salts out
• Urinary-water,
metabolic wastes and
salts out
Urinary System: Function
• It filters your blood and removes wastes
produced by your cells
• Fluid levels in the body are also maintained
by the urinary system
Organs: Kidneys (2)
• Filters all the blood in your body every 5
minutes
• Blood enters the kidney, then excess sugars,
salts, and wastes are removed
• Purified blood is returned to the circulatory
system
http://www.youtube.com/watch?v=TzwPmz5V6Xg
Cross-section of a human kidney
Organs: Ureter
• Water, salts, and other wastes flow from the
kidneys to the bladder through the ureters.
Ureters
Organs: Bladder
• Excess waste and water are stored in the
bladder
• About 1 L of urine is produced each day
Bladder
Organs: Urethra
• Water exits the body through a tube called
the urethra
Urethra
Urinary System: Problems
• When kidneys don’t filter wastes, the body
is slowly poisoned.
• High levels of glucose (sugar) can signal
diabetes.
• Dialysis: a machine that can do the job of a
broken or missing kidney. It will filter the
blood.
Dialysis
Kidney Stones
Urinary Tract Infections (UTI)
Urine Color
Medicine
Medicine or
food
Too much
water
Not enough
water
Medicine or
food
Blood
or food
Blood
or food
Healthy!
Review Movie
http://www.youtube.com/watch?v=AgDUmx7wSnw
Review Quiz
Name the organs
A
A-Kidney
B-Ureter
B
C-Bladder
D-Urethra
C
D
What system do kidneys work
with?
• Circulatory System
What is done if kidneys don’t
work properly?
• Blood is filtered in a dialysis machine
Why should women wipe front to
back?
• To avoid getting bacteria in their urethra
What color urine signals that you
are healthy?
• Pale yellow (like hay)
Excretory Lab
Results
Sand
Water, food
coloring, salt
Conclusion
1. Did all the materials pass through the filter
paper? Why or why not?
2. What part of the model is like the kidney?
3. What part of the model is like the blood?
4. What materials from this lab would end up in
the urine?
5. How is this demonstration similar to the job of
the kidneys?
6. What would happen if our kidneys did not
function properly and were unable to filter
out waste materials?