The diagram shows the flow of biomass through an agricultural food chain:
Calculate the percentage efficiency of transfer of biomass between the clover crop and humans. Include your working.
State two ways that biomass is lost from this food chain.
High levels of ultraviolet (UV) light can damage plant cells. To prevent damage, clover plants produce a protective sunscreen pigment. When UV light levels get too high, the production of this pigment switches on, which stops the plant absorbing too much light. When the UV light levels drop back to normal, the pigment breaks down slowly. Explain why this temporary protection mechanism reduces the biomass available to humans.
The breakdown of the protective pigment involves a plant enzyme (protein). Scientists have genetically modified clover plants by inserting extra copies of the gene coding for this enzyme, leading to the production of more mRNA molecules in the cells. Explain why making more mRNA allows the protective pigment to break down faster.
Scientists have found that these genetically modified clover plants produce 16%16\%16% more biomass than wild-type plants. Calculate the average increase in biomass (in kg\text{kg}kg) this would provide for humans.
Inserting extra copies of a plant's own gene into a plant is a type of genetic modification (GM). Another example of GM involves inserting a bacterial gene into a plant which makes it produce an insecticide. Suggest why the public are more likely to support genetic modification that involves extra copies of the plant's own gene rather than inserting a bacterial gene.