Two samples of tissue were taken from the same plant. Each sample had a mass of 1.0 g. One sample contained actively growing root-tip tissue and the other contained mature storage tissue.
Scientists measured the rate of ATP breakdown for three cellular processes in each sample.
| Cellular process | Rate of ATP breakdown in root-tip tissue in μmol min⁻¹ | Rate of ATP breakdown in storage tissue in μmol min⁻¹ |
|---|---|---|
| Active transport | 1.6 | 0.6 |
| Protein synthesis | 2.1 | 0.7 |
| Cellulose synthesis | 1.1 | 0.3 |
Metabolic rate is the rate at which chemical reactions take place in cells.
Calculate how many times the total rate of ATP breakdown in the root-tip tissue is that in the storage tissue.
Explain why the higher rate of ATP breakdown for protein synthesis in the root-tip tissue is linked to both a faster rate of respiration and a higher metabolic rate.
92 exam-style questions on AQA GCSE Biology 4.2 Respiration, covering 4.2.1 Aerobic and anaerobic respiration, 4.2.2 Response to exercise, and 4.2.3 Metabolism. Each one has a worked solution and a mark scheme showing where the marks go.