Excretion is one of the characteristics of all living things

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

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

3. Excretion • Skin - Sweat • Kidneys-Urine • Lungs-Carbon Dioxide + Water

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

5. renal vein renal artery bladder urethra Urea is filtered out of the blood mixed with water and excreted as Urine kidney Kidneys ureter bladder urethra

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

8. 2 urea, some salts and water are removed from bloodstream by kidney and form urine 1 blood containing water, salts and urea enters the kidney 3 the urine leaves the kidney in the ureter Blood salt urea

9. Urine is stored in the bladder before being released from the body urethra

10. respiration carbon dioxide glucose cell water energy oxygen Excretion from Lungs • carbon dioxide and water are waste products of the process of respiration in all the cells of the body

11. respiration carbon dioxide glucose cell water energy oxygen Excretion from Lungs • carbon dioxide and water are waste products of the process of respiration in all the cells of the body

12. c c o o o o o o H H H H Excretion from Lungs • the carbon dioxide and some of the water is carried to the lungs by the blood to be excreted

13. Excretion from Lungs Carbon Dioxide removed Some Water removed

14. section of skin pore sweat gland blood capillaries Excretion from Skin • 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

15. section of skin pore sweat gland blood capillaries Excretion from Skin • The sweat evaporates taking in LATENT HEAT and so the body cools.

16. Questions

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

18. bladder urethr Bladder structure and function 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?

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

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

21. 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?

22. ? 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?

23. Excretion - Summary understand the structure and function of the urinary system: bladder, renal artery, renal vein, ureter, urethra and kidney name the products of excretion: CO2, water and urea understand the function of the skin in the excretion of waste products made in the body 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

24. H/W • P61 • Q 1,2,3,4,7