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Using knowledge of the pathogenicity of HIV, explain why it can't be transmitted through inanimate objects or hand shakes with an infected person.

HIV is a virus and therefore obligately intracelluar, with a very short survival time outside of its host.

Answered by Owen F. • Biology tutor

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How can antibody neutralisation of pathogenic antigens help prevent cellular damage? (4 marks)

Prevent:Antigen attachment to cell > cell invasion > pathogen replication > toxin production.

Answered by Owen F. • Biology tutor

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Define "cellular immune response".

An immune response mediated by T lymphocytes.

Answered by Owen F. • Biology tutor

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How do you tackle AQA extract questions? (i.e. for the Aspects of Tragedy Paper)

Firstly make sure you read the extract. Once initially, just to understand the scene and then again with a pen or a highlighter to underline bits you plan on using in your essay. Take about 5 minutes to a...

Answered by Tutor123701 D. • English Literature tutor

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What are the similarities and differences between DNA and RNA?

DNA and RNA are structurally almost identical, but there are a number of key differences. The 'D' in DNA stands for deoxyribose - the sugar molecule that gives DNA a stable helical conformation (called a ...

Answered by Tristan D. • Biology tutor

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