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What is the difference between DNA and mRNA?

DNA and mRNA are both nucleic acids and are made up of a sugar, phosphates and a base. However, they are very different. Firstly by simply looking at the molecules DNA is double stranded whereas mRNA is sing...
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Answered by Emma C. Biology tutor
6120 Views

Describe the use of PCR and how exponential amplification can be achieved.

Polymerase chain reaction ( PCR ) is a technique used in molecular biology to amplify a single copy or a few copies of a segment of DNA across several orders of magnitude, generating thousands to millions of...
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Answered by Sam B. Biology tutor
8802 Views

Explain the role of the diaphragm in breathing out

The external intercostal muscles contract which moves the diapraghm upwards. This reduces the volume of the thorax and therefore with less space, the pressure in the lungs goes up. The pressure in the lungs ...
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Answered by Kai A. Biology tutor
13451 Views

What happens to the rate of an enzyme-catalysed reaction when temperature increases? And when pH changes?

As temperature increases, the molecules involved in the reaction gain kinetic energy, increasing the chances of collision between the substrate molecules and the active sites of the enzymes, a step that is n...
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Answered by Maria D. Biology tutor
12040 Views

Explain, with the use of a punnet square, heterozygous inheritance.

First, let's make sure we're clear on what heterozygous inheritance means. Hetero means different like heterosexuals are attracted to a different gender than themselves, and zygous is relating to the word zy...
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Answered by Kristina M. Biology tutor
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