1) Name the distinct features of enzymes. (2 marks)

The following list shows a number of molecules
2) Which of them are enzymes? (2 marks)

3) What is the induced fit theory? (4 marks)

4) How does pH affect enzyme activity?

5) What is the optinum pH range for pepsin? (1 mark)

6) Complete the following sentences: (2 marks)
Enzyme concentration is proportional to rate of reaction, provided...

Substrate concentration is proportional to rate of reaction until there are...

In a range of 0-35°C, the rate of reaction of an enzyme is proportional to temperature.
Above 35°C and below 0°C, enzyme activity slows down and eventually stops.
7) Explain why. (3 marks)

The true substrate for dehydrogenase is C2H5OH. In methanol poisoning, excess methanol is accidentally swallowed. In this case, methanol is a competitive inhibitor and blocks the active site of dehydrogenase. The result is a reduced rate of reaction with C2H5OH.

8) How would you treat a patient with methanol poisoning? (1 mark)

Transpeptidase is an enzyme found in bacteria. Its main function is to cross link peptide side-chains of sugar residues to form peptidoglycan, a crucial component of the bacterial cell wall. The beta-lactam antibiotic penicillin inhibits transpeptidase by irreversible inhibition.

9) Explain what is meant by irreversible inhibition. (2 marks)