1. respiration feeding responsiveness growth reproduction movement and
Excretion
is one of the characteristics of all living things
feeding
respiration
reproduction
growth
responsiveness
movement
excretion
and

2. Excretion Excretion is the removal of toxic chemical substances
Toxic substances are poisonous and can harm the cells of the body if not removed

3. Excretory Organs We have 3 excretory organs Kidneys Lungs and Skin

4. Kidneys The kidneys remove urea and salts they clean our blood
If your kidneys are damaged you may need to go on a dialysis machine

6. structure Kidneys renal vein renal artery kidney ureter bladder
urethra
renal vein
renal artery
kidney
structure
ureter
bladder
urethra

7. function bladder urethra renal artery carries blood to kidney
renal vein carries blood from kidney
kidney filters blood to remove urea
function
ureter transports urine to bladder
bladder stores urine
urethra releases urine

8. urea, which is toxic, is produced in the liver from excess protein
Toxic urea is removed by and carried by blood to the kidney
excess protein from our food is carried from the gut by blood

9. 1 blood containing water, salts and urea enters the kidney
2 urea, some salts and water are removed from bloodstream by kidney and form urine
3 the urine leaves the kidney in the ureter
salt
urea

10. urine is stored in the bladder before being released from the body
urethra

11. Lets dissect our own kidneys in the lab!

12. carbon dioxide and water are waste products of the process of respiration in all the cells of the body
energy
water
carbon dioxide

13. the carbon dioxide and some of the water is carried to the lungs by the blood to be excreted

14. Can you remember how we can prove there is water and Carbon dioxide in our breath??
Test for Carbon dioxide = Limewater
Test for water = Cobalt Chloride paper

15. Human skin has sweat glands which lead to pores at the surface – water, salt and a tiny amount of urea is excreted as sweat through these pores
section of skin
sweat gland
blood capillaries
pore

16. In Summary We have 3 excretory organs Organ Product excreted Lungs
Carbon dioxide + water
Skin
Sweat which is water and salt
Kidneys
Urea and salts in urine

17. Questions

18. One or Two?
HINT
How many of each of the following are in the human urinary system?
Kidney
Bladder
Renal artery
Renal vein
Ureter
Urethra
bladder
urethr

19. Bladder structure and function
urethr
Why is the bladder shaped like a plastic bag?
Why is the bladder situated below the kidneys?
There is a small circular muscle at the exit to the bladder. Why?

20. A D C B
Kidney location
Which answer places the kidney in the correct area of the body? A B C D B

21. Kidney The kidney is usually covered in a layer of hard fat.
Can you suggest a reason for this?

22. Kidney
All the blood in the body is filtered by the kidney, but when it is cut open there is almost no blood visible. Can you think of a reason for this?

23. Water - where and when?
Water is released from the body by the lungs, the skin and the kidney at different rates under different conditions.
How do you think each of the three excretory organs would react on a very hot day? ?

24. Excretion OB2-OB23
OB20 understand the structure and function of the urinary system: bladder, renal artery, renal vein, ureter, urethra and kidney
OB21 name the products of excretion: CO2, water and urea
OB22 understand the function of the skin in the excretion of waste products made in the body
OB23 recall that waste products are removed from the bloodstream by filtration in the kidneys in the form of urine, which contains urea, water and salts, and that urine is stored in the bladder before being released from the body