Question

PLEASE HELP

You must design a valid experiment to show that there are microorganisms in the air. What would be your dependent variable?
sterilized broth
growth of organisms in the broth
exposure to microorganisms in the air
You must design a valid experiment to show that there are microorganisms in the air. What would be your control group?
open flask with unsterilized broth
open flask with sterilized broth
sealed flask with unsterilized broth
sealed flask with sterilized broth

Answer 1

We are checking to see if microorganisms are in the air so we will keep exposure to air as the dependent variable.

A sealed flask with sterilized flask, so it is not exposed to air and it does not have any pre-existing microorganisms.