1. INTEGRATED SCIENCE THE RESPIRATORY SYSTEM 10 CMH

2. How Yeast Respire Anaerobically
Yeast is a type of fungus that has a single cell with a oval shape.
Yeast respire aerobically and anaerobically.
Yeast gets more energy from aerobic respiration.
When yeast runs out of oxygen it does not die.
Yeast produce ethanol when it respire anaerobically.
Glucose/sugar is broken down into ethanol and carbon dioxide.
The process is known as alcoholic
fermentation.
Glucose ethanol + carbon Dioxide + 210kj

3. Industrial processes Which involves Yeast
Baking of Bread
The ingredients water and yeast are mixed together to form the dough.
Dough is left for several hours to warm.
Yeast then respire anaerobically,
producing tiny bubbles of carbon
dioxide gas.
This make dough rise.

4. Ethanol is also produced in the dough but evaporates during the process.
Heat kills yeast cells before too much ethanol is produced.

5. Alcoholic Drinks Production (alcoholic fermentation)
Yeast convert sugars into ethanol and carbon dioxide gas (alcoholic fermentation).
Carbon dioxide is allowed to escape.
A solution of ethanol in water is left behind.

6. Proportion of Alcohol In Drinks
Beers 4- 6%
Wines 10-12%
Fermentation alone can not give you more than 14% percent of alcohol in drinks.
The high concentration of ethanol will poisons the yeast.

7. Rum
Spirits, such as rum contains about 40% ethanol.
This is made by distilling the fermented mixture.
Where the ethanol is separated from water.

8. Lactic Acid Fermentation
This is when some bacteria respire anaerobically.
Lactic acid is produce when the sugar is fermented.
This can be use to make butter, cow’s milk, cheese and soy sauce.
The lactic acid make the products sour when taste.

9. Mouth-to-mouth Resuscitation
When a person has an accident and stops breathing they should get artificial breathing.
Step 1
pinch the nostrils shut and tilt the head back and push the lower jaw forward. This opens the airways.

10. Step 2 Take a deep breath and open your mouth and seal your lips against the person’s mouth. Breathe out firmly but gently into the person’s mouth. This puts air into the person’s lungs.

11. Step 3
Lift your mouth away and turn your head to look at the person’s chest. If you have been successful you will see that the chest has risen and is now falling as air is leaving the lungs.

12. Step 4 Repeat step 2 and 3 at a steady rate
Step 4 Repeat step 2 and 3 at a steady rate. Breathing should start again.

13. Cigarette Smoking Effects
Nicotine
This is a poison.
It is also addictive.
This means that, once your body has got used to it, you feel that you cannot do without it.
Nicotine is a stimulant which make parts of the brain more active.
Nicotine also make blood vessels narrower and increase blood vessels.

14. Tar Tar is carcinogenic (cancerous).
Chemicals in tar damage genes that
would normally regulate how often a
cell divides.
The cells begins to divide uncontrollably, forming a lump or tumour.

15. Carbon Monoxide
Reduces oxygen supply.
Carbon monoxide binds tightly to haemoglobin.
This leave less space for oxygen to attach.

16. Cilia are Destroyed
This allow mucus build up in the respiratory tract.
Dust and microorganisms get trapped in the mucus.
The mucus then goes down into the lungs and cause a cough.