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Explain how a substitution mutation could cause an enzyme not to work (5)

The mutation changes the order of bases so there is a different triplet code present. This results in a different amino acid being coded for in the polypeptide chain. This means a different protein with a di...
EC
Answered by Evie C. • Biology tutor
8571 Views

Describe how mRNA is produced in the nucleus of a cell

Helicase (an enzyme) breaks the hydrogen bonds between the DNA resulting in two strands. Only one strand acts as a template. RNA nucleotides attracted to exposed bases according to base pairing rules (A-U, G...
RN
Answered by Rachel N. • Biology tutor
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How does DNA replication take place?

DNA replication takes place by semi-conservative replication (i.e. only half of the strand in each DNA molecule are from the original DNA molecule). First, the enzyme DNA helices is required to break the hyd...
LH
Answered by Laura H. • Biology tutor
4163 Views

Name and explain the effect of fertiliser runoff into lakes

This process is called eutrophication. Fertiliser is applied to plants because it contains a lot of ammonia and nitrates, which are needed to help a plant grow. However, if too much is applied, especially in...
KS
Answered by Katy S. • Biology tutor
5213 Views

List three differences in the composition of tissue fluid at the arterial end of the capillaries to the tissue fluid at the venous end of the capillaries.

The arterial end contains a higher concentration of oxygen than the venous end.The arterial end contains a higher concentration of glucose/amino acids.The arterial end contains a lower concentration of waste...
AE
Answered by Abdullah E. • Biology tutor
6601 Views