Laura uses a cotton swab to collect microorganisms from a hand rail and streaks a plate. On the fourth day of incubation, she does not observe visible microbial growth. Given that microorganisms are literally everywhere, give at least three reasons why Laura may not have observed microbial growth?
Added by Dana P.
Step 1
Step 1: Laura may not have prepared or brought a medium with balanced pH and salt concentrations, so microorganisms may not have had optimal growth conditions next to the handrail. Show more…
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