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What is an enzyme and explain the factors affecting it.

Enzymes are proteins. They are biological catalysts, meaning they increase the rate of reaction without being used up or changed. Different enzymes have different optimum temperatures and pHs, depending on t...
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Answered by Yusir M. • Biology tutor
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What are the non-specific defence systems of the human body that protect it from pathogens?

A 'non-specific' defence system means that its response is the same for every invader (pathogen). In the human body this includes: Skin - a physical barrier between the outside world and the inside of the bo...
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Answered by Alice H. • Biology tutor
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Compare and contrast three ways in which sperm cells and egg cells are specialised for their functions

Both sperm cells and egg cells contain a haploid nucleus, this means that they contain half the number of chromosomes of a normal diploid cell. This is so that when the egg is fertilised by the sperm there a...
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Answered by Aoife C. • Biology tutor
33564 Views

Describe the process of an action potential travelling across a synapse

An action potenial reaches the synaptic bouton causing depolarisation which opens calcium voltage gated channels. Calcium moves into the cell and causes the movement of vesicles containing acetylcholine towa...
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Answered by Ed W. • Biology tutor
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Compare DNA and RNA

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) both encode genetic information; however, there are many fundamental differences. Firstly, the sugar backbone for RNA is ribose, while for DNA its deoxy...
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Answered by Sara T. • Biology tutor
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