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Biology

A Level

List the ways in which arteries and veins differ

Arteries don't have valves, unlike veins. 2. Arteries have more elastic walls in comparison to veins. 3. Arteries have less collagen than veins. 4. Arteries have a narrower lumen in comparison to ve...

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If DNA inside a cell is damaged, a protein called p53 halts the cell cycle. With this in mind, explain how a p53 gene mutation could cause cancer to develop.

Cancer cells have damaged or mutated DNA. If p53 was functioning, it would stop the cell cycle and ensure damaged cells did not multiply. However, if the gene coding for p53 is faulty, cell division would...

Answered by Isabelle M. • Biology tutor

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What is the shape of a DNA molecule

Double helix with a sugar and phosphate backbone as well as complimentary base pairs

Answered by • Biology tutor

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What is the role of the heart in the formation of tissue fluid?

Ventricles contraction produce high blood pressure.This forces water and other substances out of the capillaries

Answered by Aya A. • Biology tutor

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Describe the process of semi-conservative DNA replication.

Semi-conservative replication is the process of making two molecules of DNA from one DNA molecule, each containing one original DNA strand and one newly synthesised DNA strand. The original double helix i...

Answered by Joseph R. • Biology tutor

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