1. End Homeostasis 5 minute poster
Work as a team to produce a poster of everything you can remember about homeostasis WITHOUT looking at your books
End

2. How does the body maintain constant water levels?
Water Balance
How does the body maintain constant water levels?
Lesson Learning Outcomes:
Describe the role of the kidneys in water homeostasis
Explain the role of ADH in water balance
Predict the effects of different drugs on the amount of urine produced
Increasing Difficulty 2

3. Water gains and losses
How is water gained?
How is water lost?

4. The Kidney The kidneys have two jobs:
Water balance
Excretion
They can change the amount of urine you make

5. GO FOR A TEN MILE RUN ON A HOT SUNNY DAY?
Urine concentration
What do you think your urine would be like if you….
GO FOR A TEN MILE RUN ON A HOT SUNNY DAY?

6. DRINK A BOTTLE OF WATER IN 30 MINUTES?
Urine concentration
What do you think your urine would be like if you….
DRINK A BOTTLE OF WATER IN 30 MINUTES?

7. Urine concentration EAT A REALLY SALTY MEAL?
What do you think your urine would be like if you….
EAT A REALLY SALTY MEAL?

8. WAIT FOR THE METRO FOR AN HOUR IN THE SNOW WITHOUT A COAT?
Urine concentration
What do you think your urine would be like if you….
WAIT FOR THE METRO FOR AN HOUR IN THE SNOW WITHOUT A COAT?

9. Summarise the role of the kidneys in water balance
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Right hand page
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Water Balance
Summarise the role of the kidneys in water balance
Summary

10. Drugs Some drugs affect the way the body produces urine
This happened in the 90s (when I was in middle school)
WHY DID LEAH BETTS DIE?
Wonderwall.

11. Explain why Leah Betts died
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Water Balance
Explain why Leah Betts died
Ecstasy
Summary

12. Why did Leah Betts die?
It was the first time she took ecstasy and it wasn’t contaminated
She wasn’t dancing so she didn’t dehydrate
She drank about 7 litres of water in a few hours
Water balance is controlled by a hormone call Anti-diuretic hormone (ADH)
ADH makes the kidney tubules more permeable to water so more water can be reabsorbed into the blood and less urine is produced
Ecstasy makes ADH production occur even when it is not needed

13. Drugs Name of Drug Affect on release of ADH
Affect on the volume of urine produced
Caffeine
Alcohol
Ecstasy

14. Drugs! Name of Drug Affect on release of ADH
Affect on the volume of urine produced
Caffeine
Suppresses ADH production
Increases the amount of urine
Alcohol
Greatly increases the amount of urine
Ecstasy
Increases ADH production
Reduces the volume of urine produced

15. Receptor in brain and skin
Negative feedback
Receptors in brain
Detects increase
Hypothalamus (brain)
Sweat Gland
brings about change (decrease)
37C
Receptor in brain and skin
Detects decrease
Hypothalamus (brain)
Muscle Shiver
brings about change (increase)

16. Draw a negative feedback loop for water balance.
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Right hand page
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Water Balance
Summary
Ecstasy
Negative feedback and ADH
Draw a negative feedback loop for water balance.