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Explain how a change in one amino acid in an enzyme molecule can stop the enzyme working.

This is because the altered amino acid codes for a different protein (an enzyme is a protein) to be created. This protein has a different 3D structure and shape meaning that it's active site, where the subst...
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Answered by Beatrix T. • Biology tutor
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Describe and explain how the structure of the small intestine is adapted for absorbing the products of digestion.

The small intestine's structure is adapted in two main ways to aid in the absorption of the products of digestion. Firstly, the small intestine's surface is covered in villi which help to increase the surfac...
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Answered by Tom D. • Biology tutor
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What is a stem cell?

A stem cell is an unspecialised cell that can undergo differentiation to form a specialised cell. Differentiation describes changes that happen to a cell that result in it transforming into a different cell ...
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Answered by Catriona C. • Biology tutor
6318 Views

How are the alveoli adapated for gas exchange

Blood leaves the right side of the heart via the pulmonary artery, which takes deoxygenated blood to the lungs so gas exchange may occur. Numerous alveoli are found here and these alveoli possess many invagi...
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Answered by Maryam A. • Biology tutor
3181 Views

Explain how vaccines work.

Vaccinations are an injection of small amount of a dead or weakened form of a pathogen that provoke a primary immune response. This causes the body to produce the correct antibodies to remove the pathogen. T...
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Answered by Eleanor M. • Biology tutor
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