Top answers

Biology
A Level

Describe the similarities and differences between RNA and DNA

Similarities: both encode genetic information; both can bind nitrogenous bases adenine, guanine and cytosine; both are polar and have a 5' end and a 3' endDifferences: RNA binds uracil, whereas DNA binds ...

CD
Answered by Conlan D. Biology tutor
5008 Views

Maltose is hydrolysed by the enzyme maltase. Explain why maltase catalyses only this reaction.

The active site of the enzyme has a specific active site that is complementary to maltose. This means that maltose can only bind to maltase to form an enzyme-substrate complex.

CB
Answered by Chloe B. Biology tutor
3643 Views

How does a transmembrane protein transport a molecule against the concentration gradient (2)

The transmembrane protein transport a molecule against the concentration by active transport (1) which requires ATP (1).

BM
Answered by Bonnie M. Biology tutor
2863 Views

Describe the process of semi-conservative replication and why is it so important?

The process of DNA replication involves unwinding the original DNA strand by the enzyme DNA helicase. This enzyme breaks the hydrogen bonds between complimentary bases forming two single ...

NM
Answered by Neha M. Biology tutor
12033 Views

How does water move up the xylem vessel?

Hydrogen bonds between water molecules give water a ‘stick’ like property called cohesion. This means molecules of water are attracted to each other. Hydrogen bonds also form between water molecules and t...

RB
Answered by Rehana B. Biology tutor
4631 Views

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