Do Now- 2/24

The diagram shows two populations of bacteria. The black circles represent bacteria that are not resistant to antibiotics, the white circles represent bacteria that are slightly resistant, and the gray circles represent bacteria that are very resistant. Starting in April, small concentrations of antibiotics were applied to the bacteria. Which statement about the results is true?

• The bacteria are more resistant over time.

• The bacteria are less resistant over time.

Monita farms have antibiotics in the animal feed. An experiment was conducted to compare antibiotic resistance in the bacteria at Monita farm to the control farm, where the animal feed does not contain antibiotics. The graphs below show the % of alive bacteria after treatment with 5 different antibiotics. Which statements about the results of the experiment are true? (Select all that apply)

• The antibiotics in the control farm killed about 50% of the bacteria.

• Most of the bacteria at Monita farm were not killed by the antibiotics.

• Most of the bacteria at Monita farm were killed by the antibiotics.

• None of the bacteria at the Control farm were affected by the antibiotics.