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.

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a