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How can you stop a cell culture from becoming contaminated?

Sterilising petri dishes and agar before use. Taping lid of petri dish whilst microbes are glowing. Sterilising innoculating loops before use.Carry out experiment near bunsen burner for updraft.
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Answered by Iona H. • Biology tutor
4028 Views

Explain how a vaccination prevents infection.

A vaccine causes white blood cells to produce anitbodies. Antibodies are proteins which kill pathogens, such as viruses and bacteria. If the body is reinfected by the same pathogen as the vaccine then the wh...
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Answered by Tomas C. • Biology tutor
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What is a reflex action and along which pathway does it travel in the nervous system?

A reflex action is an automatic rapid involuntary response, which acts to protect the body from damage. Such as when you touch something extremely hot, you involuntarily remove your hand from the hot object....
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Answered by Isobel R. • Biology tutor
8189 Views

What is an enzyme?

An enzyme is known as a biological catalyst. This is because they can speed up reactions by providing an alternative pathway, lowering the activation energy of the reaction. They are normally composed of a p...
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Answered by Liam M. • Biology tutor
5214 Views

Please explain Mitosis

Background knowledge DNA - carry the genetic code that determines characteristics of an organism Chromosomes - made from long DNA molecules, many genes all coiled up into a chromosome. A healthy person will ...
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Answered by Jacob C. • Biology tutor
6185 Views