Give three reasons why you might have a situation in which bacterial colonies were found on the first section of a streak plate, but not on sections two and three.

Hi. You have not shown the sections this question refers to, nor have you provided more information about those sections. This makes it difficult for your question to be answered. However, I will try to help you as best I can.

Generally speaking, we can consider that there was no growth of bacterial colonies in sections 2 and 3, because, for some reason, the bacteria was not inoculated in sections 2 and 3. What could also have happened, is that the bacteria in the sections 2 and 3 were eliminated, but the bacteria from section 1 managed to survive and form colonies.

Another possibility is that after inoculating the bacteria in section 1, you didn't handle the bacteria correctly in the other sections, leaving that bacteria to dry out and die.

Finally, the culture media in sections 2 and 3 could be inappropriate for bacteria to develop and form colonies.

Hownis the total magnification of a cell calculated

which of the following hypotheses can be tested with experiments? select all that apply

1.) a diet low in sugar reduces the risk for heart disease
2.) coffee increases subject performance on intelligence tests
3.) people that brush their teeth live longer than those who don't brush their teeth
4.) scientists will find a cure for cancer before the year 2020

I know that 4 isn't the answer so I selected the other three and it said I was wrong. isn't a hypotheses something that can be experimented on so can't all of the three have experiments If I'm making sense ​

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