1. 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?

The Laura tried to grow micro-organisms in culture broth medium in Petri-plates but the microbial growth was not observed even on the fourth day of culture which could be due to:

1. Laura could have not provided the correct broth medium maintaining the with pH and salt concentrations.

2. Microorganisms did not get optimal growth conditions.

3. The bacterial source could have died after the collection which could have lysed after their death and thus no longer visible.

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.

it would lead to upper respiratory infections and pneumonia.