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