4.2 Respiration

1. 4.2 Respiration 7.1.d Students know that mitochondria liberate energy for the work that cells do and that chloroplasts capture sunlight energy for photosynthesis.

2. What is Respiration? • Respiration- the process but which cells obtain energy from glucose • Key Concept: “During respiration, cells break down simple food molecules such as sugar and release the energy they contain. • Cells of all living things carry out respiration because they need energy • Cells store energy like we store money in a bank- capture energy from sun and save during photosynthesis- when need energy the break down carbohydrates in respiration

3. Two Stages of Respiration • During respiration, cells break down simple food molecules such as sugar and release the energy they contain.

4. What is Respiration? • 2 meanings for respiration- cellular respiration and breathing • Products of respiration-carbon dioxide and water • We breathe out carbon dioxide • Plants undergo Photosynthesis and make its own food (sugar) • Animal cells (and some others) get their glucose from eating plants or animals that ate plants • Respiration and Photosynthesis keep levels of oxygen constant on Earth • Respiration video

5. What is Respiration? • Respiration equation: • Raw Materials Products Oxygen Sugar Carbon Dioxide Water Yields Video on Cellular respiration

6. Photosynthesis and Respiration • You can think of photosynthesis and respiration as opposite processes.

7. The 2 Equations + energy

8. Fermentation • Fermentation- energy releasing process does not need oxygen • Key concept: “Fermentation provides energy for the cell without using oxygen.” • Amount of energy released is less than during respiration Mitochondria

9. Fermentation- Alcoholic • Type of fermentation when yeast and some other single celled organisms break down sugars • Called alcoholic because one of its products is alcohol • Other products are carbon dioxide and energy • Important to bakers- raises dough and creates bubbles in alcohol drinks

10. Fermentation- Lactic Acid • Takes place at times in your body • When running muscle cells use oxygen faster than it can replace it • Cells lack energy and fermentation occurs • Product is lactic acid • When the lactic acid builds up you feel pain (and weakness) in your muscles

11. Section 2: Respiration • What events occur during respiration? • What is fermentation?