WATER & WASTE

1. WATER & WASTE WATER is crucial to our survival. Whilst we can go a month without food, we can only survive a few days without water. Our body contains a lot of water – if you took all the water out of our bodies (the liquid used in blood etc and the fluid inside cells) it would probably amount to around 90% of our weight!

2. Gaining Water • Our bodies gain water in three different ways. • Water from Drinking • Water from Food • Water from Cell Respiration food + oxygen  carbon dioxide + water

3. Losing Water • Our bodies lose water in four different ways. • Water in Sweating • Water in Breathing • Water in Urine • Water in Faeces

4. Water Balance • Most mammals are not designed to store water, and so they need to have a constant supply. • Therefore the water we gain each day must equal the water we lose. Total Water Gain = Total Water Loss

5. Water and Waste -The Kidney

6. Structure and Function of Kidney

7. Function of the Kidneys • The Kidneys have two main functions, which are: • Maintaining a water balance. • Getting rid of poisonous waste substances from within the body (Urea).

8. Urea • The poisonous waste Urea is made in our _________. • It is made when excess _______ _______ are broken down. • The urea is then transported by the blood to the kidneys were it is __________. liver amino acids removed

9. Function of the Kidneys • The Kidneys carry out its two functions through two processes, which are: • Filtration • Reabsorption • These processes take place in millions of tiny filtering units called __________. nephrons

10. From renal artery Nephron Glomerulus Bowman’s capsule • _______ • _______ • _______ • _______ • all filtered • out Glucose Water Salt urea Collecting duct glucose _________ reabsorbed __________ And ______ reabsorbed Water salt Blood Capillary Final urine = __________ __________ __________ to renal vein Urea Some salt Some water To the URETER

11. Nephron • The Glucose, Water, Salt and Urea which are filtered out of the Glomerulus into the Bowmans Capsule are referred to as the G___________ F____________. • The final Urine is then transported to the B____________ via the U_________. lomerular iltrate ladder reter

12. Water Regulation - ADH ituitary • ADH - Anti-Diuretic Hormone • It is produced by the P_________ gland in the brain. • ADH controls the volume of water reabsorbed into the blood.

13. Water Regulation - ADH • When the body is dehydrated, for example in hot climates, during vigorous exercise, or by the consumption of salty foods then the blood will have a low water concentration. • The pituitary gland in the brain will produce a _____ level of ADH, which causes a ______ volume of water to be reabsorbed to rehydrate the body. • Therefore only a ______ volume of urine is produced. high large small

14. Water Regulation - ADH • However, if the body is overly hydrated for example through drinking large volumes of liquid then the blood will have a high water concentration. • The ________ gland in the brain will produce a ______ level of ADH. • This results in a _____ level of water to be reabsorbed and so a ______ volume of urine is produced. pituitary low lower large

15. Kidney Failure & Treatment • If both kidneys stop working due to either disease or damage this is known as T_____ K_________ F_________. • There are two ways of treating kidney failure, which are: • D_________ on a kidney machine. • A kidney T____________. idney ailure otal ialysis ransplant

16. Kidney Failure & Treatment • List some of the benefits of Dialysis and Kidney Transplants. • List some of the limitations of Dialysis and Kidney Transplants.

18. How Dialysis Works • The blood is bathed in a rinsing fluid which is carefully designed to have the same concentration of useful substances as the blood • Therefore only waste materials will diffuse out of the blood. Urea