Question

A scientist found that a Petri dish from an experiment had not been cleaned several days earlier. In the dish, she discovered a bacterial culture that she had not seen during the experiment. How could she gather evidence to support a claim about whether the bacteria had developed from the material left from the earlier experiment? a)Take a sample of the bacteria and grow it in an incubator. b)Gather dirty Petri dishes from other labs to see if they grow the same bacteria. c)Check all the clean Petri dishes for residue from the previous experiment. D)Try the original experiment again, do not clean some of the Petri dishes, and see if the bacteria grow.

Answer 1

Answer: D

Step-by-step explanation:

I had this same question before. Hope it helps:)

Answer 2

D

Step-by-step explanation:

The best way she can gather evidence to support a claim of the bacteria developing from the material left from the earlier experiment would be to repeat the original experiment again, leave some of the Petri-dishes uncleaned, and then see if the same bacteria would grow on the uncleaned Petri dishes.

If indeed the bacteria developed from the material left from the earlier experiment, the same bacteria should grow on the uncleaned Petri dishes in the second experiment. If they do not grow, it means that the source of the bacteria is from somewhere else within the lab.

The correct option is D.