Question

(a) A student investigates antibiotic resistance in one strain of bacteria.
      They use five different antibiotics on paper discs.
     The antibiotic discs are placed in a Petri dish with the bacteria and left for three days.
     Fig. 7.1 shows the results.

   Identify the antibiotic in Fig. 7.1 that is most effective against this strain of bacteria.
   Give one reason for your answer.
   antibiotic ……………………………………
   reason …………………………………………………………………………………

(b) The differences in antibiotic resistance in bacteria are caused by random mutation.
      (i) State the structure in a cell where mutation occurs.
      (ii) State the type of radiation that increases the rate of mutation.

(c) Explain why the development of antibiotic resistance in bacteria is an example of evolution.