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Outline the "Sliding Filament Theory" of muscle contraction.

In the resting state, the myosin heads have a partially hydrolysed ATP molecule (ADP + Pi) giving them potential energy. When there is an influx of calcium ions as a result of sarcolemma depolarisation, the ...
SM
Answered by Sohail M. • Biology tutor
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How are genetics linked to natural selection?

A population will always have some level of genetic variation for a specific character, giving different variants of the same character. Some characters are essential for fitness and influence survival, thes...
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Answered by Rafaelle B. • Biology tutor
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How do alveoli create a surface for efficient gas exchange?

This kind of question is extremely common in A level biology, they want you to explain a system and apply your knowledge of biological principals to it. To understand alveoli we need to understand the concep...
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Answered by Matthew C. • Biology tutor
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Explain how the human eye has both high sensitivity and high acuity.

The human eye has high sensitivity because many rods connect to a singular neurone, so many weak generator potentials combine to reach the threshold and trigger an action potential. The human eye has a high ...
AM
Answered by Anna M. • Biology tutor
4687 Views

What is the structure and function of a nerve cell?

Nerve cells serve an important function in our bodies to relay information as electrical signals from the periphery to the central nervous system. Nerve cells are also called 'neurons' and can be as long as ...
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Answered by Amelia H. • Biology tutor
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