1. Respiration happens continuously in most animal cells and some plant cells. The term “aerobic respiration” means “breathing” Respiration happens within the ribosomes of our cells All animals use some of the energy from respiration to keep warm Animals store excess glucose as starch

2. The equation for aerobic respiration is carbon dioxide + waterGlucose + oxygen + energy Deep breathing during exercise helps remove oxygen from our cells Plants use some of the energy released during respiration to build sugar and nitrates into fats During exercise our heart beats faster to reduce blood flow to our muscles During aerobic respiration oxygen is used to release sugar from glucose.

3. Our topic today is …. Anaerobic respiration And our learning objectives are: How do our muscles get the extra energy needed during exercise? How do cells get energy when glucose or oxygen runs low? What’s released when cells respire without oxygen? Why doesn’t lactic acid damage enzymes and cells? Why do we need to breathe so deeply after vigorous exercise?

4. How do our muscles get the extra energy needed during exercise?

5. How do our cells get energy when glucose runs low? Glucose provides instant energy but is not easily stored Some of the extra glucose we eat is turned into Glycogen, a carbohydrate which can be stored in the muscles. 1. At start of exercise body uses 2. Glucose quickly runs out so muscles start using their stores of Oxygen + glucose carbon dioxide + water + energy

6. How do cells get energy when oxygen runs low? Usain Bolt breathes once during the whole 100m sprint. How does this provide enough oxygen for his muscle cells to release energy? http://www.youtube.com/watch?v=By1JQFxfLMM

7. During intense exercise cells can break down glucose without any ………. This is called ………………………….. respiration Glucose energy + lactic acid The glucose is not ……………… broken down. …….. energy is released than in aerobic resp. ……… acid is produced in this type of respiration What’s released when cells respire without oxygen?

8. Anaerobic respiration doesn’t replace aerobic respiration Anaerobic respiration tops up the released energy when aerobic respiration Alone isn’t enough!

9. What type of exercise causes muscle fatigue? Independent variable (the thing we changed on purpose between tests) Dependent variable (the thing you measured) Control variables (the things you kept the same) Variables we should have controlled but couldn’t

10. What type of exercise causes muscle fatigue? Independent variable (the thing we changed on purpose between tests) Dependent variable (the thing you measured) Control variables (the things you kept the same) Variables we should have controlled but couldn’t

11. Why doesn’t lactic acid damage enzymes and cells? Blood flowing past our muscle cells …………………………… the lactic acid. If you repeat exercise before your muscles have had time to recover the build up of lactic acid causes muscle…………………. (your muscles don’t work so well / contract less efficiently) Higher only After exercise you use …………. to break down lactic acid into carbon dioxide and water. The extra oxygen needed to do this is called an “oxygen ………….”