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Biology

A Level

Describe the process of eukaryotic DNA replication

DNA helicase unzips and unwinds the DNA double helix by breaking hydrogen bonds between complementary base pairs. This exposes the bases on two strands creating template strands. Free floating nucleotides...

Answered by Louis B. • Biology tutor

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What does ELISA measure?

ELISA, an acronym for enzyme linken immunoabsorbant assay, is a means of measuring the amount of a specific antibody in serum through treating a 96 well plate with antigens that stick well to the plastic ...

Answered by Kyle M. • Biology tutor

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State three differences between DNA and mRNA molecules

DNA contains the base Thymine, whereas mRNA contains Uracil DNA is double stranded whereas RNA is single stranded DNA contains deoxyribose sugar, whereas mRNA contains ribose sugar DNA is long whereas mRN...

Answered by Charlotte B. • Biology tutor

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What happens to the filtrate in the loop of Henle?

The point of the loop of Henle is to reduce the quantity of water in the filtrate and so reduce water loss. The loop is split into three key areas: The descending limb, the thin ascending limb and the thi...

Answered by Sam M. • Biology tutor

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Which organelle is expected to be found in above-average quantities in cardiac tissue and what is the purpose of this organelle?

Cardiac tissues such as those present in the heart have a high energy requirement as they must contract strongly to facilitate the transportation of blood around the body. This requires a high level of en...

Answered by Harry C. • Biology tutor

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