Biologi

a9-1
1. Cellular respiration is the process that releases energy by breaking down molecules in food in the presence of oxygen.
2. Glycolysis produces 2 molecules of pyruvic acid, 2 molecules of ATPand 2 molecules of NADH.
3. Alcoholic fermentation and lactic acid fermentation.
4. A calorie is the amount of energy required to raise the temperature of 1 gram of water 1 degree Celsius. ACalorie is 1000 calories.
5. Both are electron carriers.
6. Similar: Both provide energy to cells in the absence of oxygen. Different: Alcoholic fermentation produces alcohol, carbon dioxide and NAD+,while lactic acid fermentation produces lactic acid and NAD+.
9-2
1. Pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions.
2. The electron transport chain usesthe high energy electrons from the Krebs cycle to convert ADP to ATP.
3. Cellular respiration enables the cell to produce 34 more ATP molecules per glucose molecule in addition to the 2 ATP moleculesobtained from glycolysis.
4. 36
5. The energy flows in photosynthesis and cellular respiration take place in opposite directions. Photosynthesis is the process that “deposits” energy while cellularrespiration is the process that “withdraws” energy.
6. The energy in glucose is “saved” and can be “withdrawn” when the body needs it.
1. c 6. b
2. b 7. c
3. b 8. b
4. c 9. a
5. b 10. b
11. Acalorie is the amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius. Cells break down high-calorie molecules in a series of steps, releasing the stored energy a smallamount at a time.
12. During glycolysis, glucose is broken down into two molecules of pyruvic acid. The other products are ATP molecules and high-energy electrons that are picked up by NAD+.
13. Afterglycolysis, if oxygen is available, a cell might carry out the rest of cellular respiration. If oxygen is not available, some cells carry out the rest of fermentation.
14. 602 + C6H12O6 -> 6CO2...