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Biology

A Level

Emphysema is a disease of the lungs. Explain why people suffering from this condition may feel weak and short of breath.(6 marks)

Emphysema is an obstructive lung disease(1), where alveoli collapse due to break down of elastin in their walls(2). This means that the lungs cannot recoil(3), making expiration difficult. There is less s...

Answered by Sara I. • Biology tutor

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Succinate is converted to fumarate by the enzyme dehydrogenase. This reaction can be inhibited by adding malonate. a) What are enzymes and what are their function? Use this information to explain how malonate acts as an inhibitor.

a) What are enzymes and what are their function? Use this information to explain how malonate acts as an inhibitor.

What are enzymes? Enzymes are proteins that act as catalysts in living cel...

Answered by Laura S. • Biology tutor

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Suggest and explain why the combined actions of exopeptidases and endopeptidases are more efficient than exopeptidases on their own.

Endopeptidases hydrolyse internal (peptide bonds) OR exopeptididases remove amino acids/hydrolyse (bonds) at the ends therefore there are more ends/increase in surfacae area for expopeptidases to work on....

Answered by Flora T. • Biology tutor

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Endopeptidases and exopeptidases are involved in the hydrolysis of proteins. Name the other type of enzyme required for the complete hydrolysis of proteins to amino acids.

The other type of enzyme required is a dipeptidase.

Answered by Flora T. • Biology tutor

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In genetics, what is sex linkage and give an example

Sex linkage refers to a trait which is coded for by a gene on a sex chromosome, in mammals these are the X and Y chromosomes. As males are XY and females XX, alleles on these chromosomes have different pr...

Answered by Shirin E. • Biology tutor

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