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How is DNA replicated, and why is this method of replication important?

DNA is replicated in a semi-conservative manner, which means that both 'parental strands' are used as templates. This ensures that genetic information is passed onto offspring without any changes (diagram) D...
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Answered by Salima B. • Biology tutor
3268 Views

What are the differences between directional and stabilising selection? Give an example of each.

In directional (a.k.a. adaptive) selection, one extreme of a population has a selective advantage i.e. is fitter than other individuals of the population. This causes a directional shift towards this extreme...
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Answered by Ben S. • Biology tutor
5433 Views

Can you explain the oxygen dissociation curve.

What is the graph telling us?On the graph, we can see two axes. We have partial pressure of oxygen on the X axis and Hb saturation on the Y axis. Partial pressure is another way of saying how much oxygen the...
TK
Answered by Thomas K. • Biology tutor
4635 Views

What is the link between electrical activity of the heart and its contraction?

The electrical current is produced in the SA node (the primary pacemaker of the heart) and travels to the AV node via fibres in the walls of the atria. These impulses cause the muscular walls of the atria to...
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Answered by Stephen M. • Biology tutor
6963 Views

Can you explain the oxygen dissociation curve.

What is the graph telling us? On the graph, we can see two axes. We have partial pressure of oxygen on the X axis and Hb saturation on the Y axis. Partial pressure is another way of saying how much oxygen th...
TK
Answered by Thomas K. • Biology tutor
2984 Views