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Biology
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What causes cancer?

There are lots of different types of cancer which affect different tissues in the body, and two cancers of the same type may not have the same causes. This makes cancer interesting, but also potentiall...

FH
Answered by Frederick H. Biology tutor
8303 Views

What is an allele?

  1. In the nucleus of the cell, there are pairs of chromosomes which carry the same genes in the same places. 2) Alleles are different versions of these genes.3) For example, a person may have an allele...
ES
Answered by Ella S. Biology tutor
8190 Views

Why do we vaccinate people - how does it work?

Vaccination is an important method used in healthcare to prevent people from getting certain diseases. Vaccines contain a dead or weakened (attenuated) form of a pathogen, and the immune system res...

ES
Answered by Ella S. Biology tutor
3797 Views

Explain the principles of PCR

The Polymerase Chain Reaction (PCR) is a method of DNA amplification in vitro. It consists of 3 stages - denaturation, annealing and extending. PCR relies on the use of a thermophilic Taq polymerase en...

DB
Answered by David B. Biology tutor
4975 Views

State the differences between introns and exons.

Introns and exons are parts of genes - exons code for proteins, whereas introns do not, ie: exons are converted into messenger RNA to allow these parts of the gene to then be transcribed into protein. ...

DB
Answered by David B. Biology tutor
13006 Views

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