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Biology

A Level

What is the difference between the pulmonary and systemic circuits of the cardiovascular system?

The systemic circuit carries oxygenated blood from the heart around the body then carries the deoxygenated blood from the body back to the heart. The blood leaves the left ventr...

Answered by Olivia S. • Biology tutor

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Describe the process of evolution (6 Marks)

Mutations in genetic code occur naturally leading to different alleles in genes. (1 mark)

This leads to variation within a species. (1 m...

Answered by Jack W. • Biology tutor

19945 Views

Describe the ways in which LDLs and HDLs affect the formation of atheromas.

Remember that often in A-level exams you can get marks from specific key words and phrases, so first of all try to remember everything you know about the topics in the question (

Answered by Iona D. • Biology tutor

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How is the diffusion of gases between the alveoli and the alveolar blood vessels facilitated?

Alveoli are small sacs at the end of the terminal branches of the lung (the brochioles). It is at the alveoli where gas exchange takes place - oxygen moves into the blood and carbon dioxide is removed. Th...

Answered by Katy C. • Biology tutor

14548 Views