Loading subjects
Life Processes at the Cellular Level · Part 3 of 5
9 exam-style questions with model answers, plus 12 quick multi-choice questions — every question on this part of the standard, grouped by the 3 pages of notes they come from.
Write a full answer before you reveal the model one. That comparison is where the learning happens.
Write the word equation for photosynthesis, and name the organelle and the pigment involved.
Explain why a plant needs to respire, given that it makes its own glucose by photosynthesis.
A sealed glass container holds a healthy pondweed plant in water. Over 24 hours, the oxygen concentration in the water rises during the day and falls at night. Discuss the processes responsible, and explain what would happen to the plant if the container were kept in complete darkness for a week.
State where in the chloroplast each phase of photosynthesis occurs, and name the products of the light-dependent phase.
Explain why the light-independent phase cannot continue for long in the dark, even though it does not use light directly.
Researchers supplied a plant with water containing a labelled form of oxygen, and separately with carbon dioxide containing a labelled form of oxygen. The labelled oxygen gas released by the plant came only from the water, not from the carbon dioxide. Discuss what this shows about the two phases of photosynthesis, and evaluate what conclusion could and could not be drawn if the experiment had used labelled carbon instead.
Name three factors that can limit the rate of photosynthesis, and define the term limiting factor.
Explain why a plant grown in soil lacking magnesium ions photosynthesises slowly, even in bright sunlight and warm conditions.
A commercial glasshouse grower in Canterbury is deciding whether to invest in artificial lighting, a carbon dioxide enrichment system, or heating, in order to increase tomato yield through the winter. Discuss how the grower should decide, and evaluate the risks of choosing wrongly.