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What is an enzyme and what effect does temperature have on enzyme activity? (6 marks)

An enzyme is a globular protein that acts as a biological catalyst. They work by reducing the activation energy of chemical reactions, which increases the rate of reactions. All enzymes have an optimum tempe...
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Answered by Isabel O. • Biology tutor
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What are the different protein structures?

There are 4 levels you use to describe protein structure. Primary Structure - This is the simplest structure of a protein. It is essentially the sequence of amino acids that form a protein. Secondary Structu...
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Answered by Nandesh P. • Biology tutor
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To what extent do the structures and functions of DNA and RNA differ?

Firstly, there are chemical differences between the two nucleic acids. DNA has the following structural properties:-double stranded and anti-parallel polymer held together by (relatively) weak hydrogen bonds...
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Answered by Adam W. • Biology tutor
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What is the difference between viral antigenic drift and antigenic shift?

Both antigenic shift and drift are used by viruses to adapt to selection pressures and avoid host immune systems. Antigenic shift is a slow change in the viral genes over time due to replication errors and r...
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Answered by Sophie W. • Biology tutor
13165 Views

How is an electrical impulse transmitted through the heart?

Contraction of the heart is myogenic meaning it initiates from within the heart muscle itself (myo=muscle, genic= created). Therefore, no extra nerves need to signal the heart to contract which is important ...
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Answered by Rebecca Z. • Biology tutor
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