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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
3960 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
15977 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
8741 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
3266 Views

How does a mutation lead to a non-functional enzyme?

Chanege in base sequence= change in sequence of triplet codes= change in sequence of amino acids= change in primary structure= change in hydrogen/ionic/disulfide bonds= change in tertiary structure= change i...
SO
Answered by Samatar O. • Biology tutor
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