Question

could explain this result? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.A streak plate achieves isolated colonies by physically diluting the culture as it is spread over the plate.After incubation, you observe that your streak-plate has heavy, uniform growth but no isolated colonies. Which of the following could explain this result? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.1. The specimen was a mixed culture.2. The plate is contaminated.3. Area three of the streak plate crossed into area one of the streak plate.4. The loop was not properly sterilized between plate sections.

Answer 1

Answer:

Option 3 and 4 are most likely correct

Explanation:

Option 3: We know that area 1 would contain heavy streaking and not single colonies. Therefore, if the loop crosses area 3 and enters area 1, it will definitely result in heavy streaking again.

Option 4: We always need to sterilize properly the loop when streaking in different areas. If we don't do it, it is possible that the loop contains a lot of bacteria that would be streaked again.

Options 1 and 2 are incorrect because, according to question, there is a uniform growth but no isolated colonies. So, contamination or mixed culture would not produce uniform growth streaking rather mixed with other bacterial types.