1. Unit 2: Cells and Systems
Topic 3: Excretory System

2. Excretory System Basically the waste management of your body
Excretion is the removal of waste from the body
Our bodies produce lots of waste, some of it toxic, so we need to remove it
What waste might our body create? HINT: think circulatory system

3. Excretory System Basically the waste management of your body
Excretion is the removal of waste from the body
Our bodies produce lots of waste, some of it toxic, so we need to remove it
What waste might our body create? HINT: think circulatory system
Excess Water
Excess salt
Solid waste (poop)
Ammonia
CO2, etc

4. Two Major Toxic Substances
Carbon Dioxide
Need to remove this from our blood
Ammonia
Our cells break down proteins and create Ammonia
Our Liver does a good job at breaking it down
Anybody have a cat? Know that funky smell from the litter box? It is because Ammonia and Ammonia like substances build up in the litter box!

5. The Liver The Liver is our detoxifying organ
Breaks harmful substances down into less harmful substances to be excreted
Breaks Ammonia down into Urea
Breaks down Alcohol!

6. The Liver The Liver is our detoxifying organ
Breaks harmful substances down into less harmful substances to be excreted
Breaks Ammonia down into Urea
Breaks down Alcohol!

7. The Liver The Liver is our detoxifying organ
Breaks harmful substances down into less harmful substances to be excreted
Breaks Ammonia down into Urea
Breaks down Alcohol!

8. The Kidneys Kidneys are the main organ of excretion
They filter the blood removing unwanted
Urea
Water
Salts
Other excess substances
Each drop of blood is filtered 300 times a day!
Keep a balance of water in your blood!

9. The Kidneys
Nephron
Cool story bro, but how do they actually work?

10. The Kidneys In summary Kidneys filter blood using nephrons
They are capillaries! (good for diffusion, remember????)
About 1 million per kidney!
Waste material leaves the blood and exits a tube in the nephron that leads to the bladder

11. The Bladder Kidneys connect to the by the Ureter
Waste (Urine) goes down Ureter and enters the bladder
When the bladder fills up (around 1L!!!) you pee out of your Urethra

12. Cool Facts Caffeine and Alcohol are Diuretics
Makes your bladder filter out more water than necessary. Can result in dehydration
Oh, and Caffeine also has an effect on the stomach, releasing hormones, causing your colons to kick in
Makes you poop more
Morale of the story
Coffee keeps you in the bathroom!

13. The Skin Ever lick your sweat?.....totally normal thing to do
Tastes salty! That’s because sweat glands excrete excess salt from your body in the form of sweat!

14. Diagnosing Disease with Urine
What is in your urine can inform doctors of what is wrong!
Too much glucose?
You might have diabetes because your body can’t process glucose properly and is now excreting it because there is too much in the blood
Blood?
Perhaps your kidneys are damaged and aren’t retaining blood properly
Kidney Stones of Dismay

15. Diagnosing Disease with Urine
Dialysis Machine
A machine that does the same job as your kidney
People with damaged or diseased kidneys have to sit at this machine for four to six hours, three days a week