Genetic Diversity

Question 1

State 6 aseptic techniques?

Answer 1

Wipe down surfaces with antibacterial cleaner, before and after the experiment. Use a Bunsen burner in the work space so that convection currents draw microbes away from the culture. Flame the wire hoop before using it to transfer bacteria. Flame the neck of any bottles before using them to prevent any bacteria entering the vessel. Keep all vessels containing bacteria open for the minimum amount of time. Close windows and doors to limit air currents

Question 2

Why is bacteria incubated at 25°c?

Answer 2

To prevent the growth of pathogens, which occurs at higher temperatures

Question 3

How can you compare the effectiveness of different antibiotics applied to the same bacteria?

Answer 3

Measure the diameter and calculate the are of the zone of inhibition on the agar(clear zone)

Question 4

What does zone of inhibition indicate?

Answer 4

The bacteria killed by the antibiotic. The larger the zone the more effective the antibiotic. If an antibiotic has very little or no zone of inhibition, the bacteria is likely resistant to the antibiotic

Question 5

State the hazards and precautions of This practical

Answer 5

Naked flame, keep away from flammable materials, tie hair up, wear goggles. Bacteria is a biohazard, use disinfectant and wash hands, dispose of bacteria safely. Disinfectant is flammable, keep away from make flame

Question 6

Why should the lid not be completely taped to the Petri dish?

Answer 6

To allow oxygen to enter the Petri dish preventing the growth of harmful anaerobic bacteria

Question 7

Describe the graph that can be plotted from the results of this practical

Answer 7

A bar chart of zone of inhibition against antibiotic