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a) What is the function of the atrioventricular valves? b) When the ventricles are contracting, are the arterioventricular valves open or closed? c) Explain why the muscle walls of the atria are thinner than the walls of the ventricles.

a) To prevent backflow of blood from the ventricles into the atria.b) Closedc) The atria only have to pump blood into the ventricles, where as the ventricles have to pump blood at a high pressure all the ...

Answered by Catherine O. • Biology tutor

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Explain briefly how mutations in the genome can lead to cancer. In your answer refer to and explain the process of protein synthesis.

The central dogma of modern genetics is simple: DNA - RNA - Protein (and, due to reverse transcriptase, RNA - DNA). It can therefore be seen that alterations in DNA sequence can have the downstream effect...

Answered by Lynden R. • Biology tutor

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Describe how mRNA is produced in humans.

DNA helicase separates the strands by breaking the hydrogen bonds.One of the strands is used as a template to transcribe the mRNA.(Complementary) base pairing occurs with free RNA nucleotides.A→U, T→A, C→...

Answered by • Biology tutor

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Why does oxygen bind to haemoglobin easier the second time?

Binding the first oxygen molecule leads to a change in the tertiary structure of haemoglobinThis uncovers the second haem binding site for another oxygen molecule to atta...

Answered by • Biology tutor

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