Essay questions.

Date: 2015-10-07; view: 502.

1. Describe the significance of water to living organisms with respect to thermal, cohesive and solvent properties (10).
2. Draw and label a structure of DNA (6).
3. Outline the steps involved in one of following processes: DNA replication, DNA transcription or DNA translation (10).
4. Compare RNA and DNA (6).
5. Outline the differences between aerobic and anaerobic cell respiration. Mention both lactic acid fermentation and alcoholic fermentation (10).
6. Explain why enzymes only work with specific substrates. In your answer mention lock-and-key theory (6).
7. Thousands of different enzymes have been discovered.
1. Explain the reasons for cells needing to have many different enzymes in their cytoplasm (5)
2. Explain how different chemical reactions are catalyzed by different enzymes (5)
3. Suggest reasons for almost all enzymes being proteins rather than other biochemicals (4).
8. Outline the use of lactase during production of lactose-free milk (5).

9. Outline the effect of temperature, light intensity and carbon dioxide concentration on the rate of photosynthesis (7).

1. Draw each of the following with proper axis:
1. Graph showing effect of increasing temperature on the rate of reaction of an enzyme-catalyzed reaction (n your answer comment on denaturation) (3);
2. Graph showing effect of substrate concentration on the rate of reaction of an enzyme-catalyzed reaction (3);
3. Graph showing effect of pH on the rate of reaction of an enzyme-catalyzed reaction (3);
4. In your own words, explain why each of the above graphs has the shape it has (4).