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Describe a simple food chain and the trophic levels within it

Grass -> rabbit -> Fox -> Crow -> Bacteria + FungiGrass = producer - first trophic level, uses photosynthesis to convert carbon dioxide and water to glucose Rabbit = primary consumer - second tro...
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Answered by Ashley C. Biology tutor
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Why does anaerobic respiration have a lower ATP yield than aerobic respiration? (4 marks)

During anaerobic respiration only glycolysis can occur as oxygen is not present to act as the final electron acceptor in oxidative phosphorylation, therefore only substrate level phosphorylation can occur. I...
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Answered by Amy D. Biology tutor
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Outline the action of B lymphocytes following initial contact with an antigen or antigen presenting cell. (6 marks)

There are 4 stages to the response of B lymphocytes upon contact with antigens. These are antigen presentation, clonal selection, clonal expansion and differentiation. During antigen presentation the lymphoc...
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Answered by Amy D. Biology tutor
3071 Views

Describe the process of diffusion?

Diffusion is the process where water molecules move from a negative water potential to a more negative water potential through a semi permeable membrane.
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Answered by Fawcett G. Biology tutor
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Describe how ions, water and sugar are obtained and transported through plants. In your answer you should refer to materials moving upwards and downwards in a plant. (6 marks)

Since this is a 6 marker, it is important for you to firstly express yourself coherently, and secondly write the 'key words' that examiners look for. The question is referring to the transport processes of t...
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Answered by Zahra I. Biology tutor
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