State one difference between viruses and bacteria.

Discuss three methods in which the activities of humans has created an increase in the resistance to penicillin in bacteria populations.

viruses smaller than bacteria;

viruses do not have a nucleus/cytoplasm/cell membrane/cell wall/ribosomes;

viruses are not cells;

viruses do not feed/excrete/grow;

Allow viruses are not living/alive.

overuse of antibiotics has increased proportion of resistant bacteria;

use of penicillin in animal feedstock has introduced antibiotics into human food chain (increasing proportion of resistant bacteria);

patients not completing course of antibiotics increases proportion/spread of resistant bacteria;

Most candidates scored the mark in (a).

A number of journalistic responses were given in part (b) where candidates did not discuss the activities of humans that have created an increase in resistant bacteria. Some candidates misread the question and discussed how penicillin had been modified to combat resistant bacteria. Overuse and developing resistance was generally the only valid reason given.