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Describe and explain the effects of pH, temperature, enzyme concentration and substrate concentration on enzyme activity

pH : All enzymes have an optimum pH value which is very specific. This is because hydrogen ions and hydroxide ions have very significant changes on the tertiary structure of an enzyme, which can cause substr...
EO
Answered by Eloise O. • Biology tutor
16584 Views

Putting bee honey on a cut kills bacteria. Honey contains a high concentration of sugar. Use your knowledge of water potential to suggest how putting honey on a cut kills bacteria.

Once honey is added to an infected cut, the osmotic gradient favours water moving from the bacterial cells to the honey. This is because the water potential is lower in the honey. As a result of the loss of ...
HM
Answered by Harry M. • Biology tutor
3865 Views

Why is it that an action potential only travels in one direction?

(draw/picture of nerve cell with its ion channels and after learning about the action potential trace and how it's derived) After each action potential, see on the trace there's a refractory period where the...
JL
Answered by Jasmine L. • Biology tutor
15856 Views

Why is the probability of inheriting Cystic Fibrosis 25% if both parents are only carriers? How did you get that figure?

(This would be after I have introduced the punnett square - I will draw this out for the student) Remember that each parent contributes one allele for a given gene to their offspring. For cystic fibrosis we ...
JL
Answered by Jasmine L. • Biology tutor
8641 Views

Why do 3 protons need to pass from the intermembrane space into the matrix of the mitochondrion in order to form 1 ATP molecule?

It has to do with the structure of the ATP synthase protein. The part in the centre moves 120 degrees with each prototon that passes through. This makes the 3 ATP/ADP binding sites to change shape. Each of t...
BB
Answered by Beatrice B. • Biology tutor
3189 Views