Describe how each of the following physical factors affect microbial growth and aid in classification: a. temperature b. pH c. molecular oxygen d. osmotic pressure.

Define the terms that are used to describe chemical control ofmicrobes.

A. Antibiotics, such as gentamicin, are used in media to prevent growth of susceptible microbes. Is gentamicin media a selective, differential or enrichment media? B. Sorbitol is a sugar alcohol that all Escherichia bacteria can normally ferment into an acidic waste compound. This acidic end product is detected by including a pH indicator in the agar and noticing a color change. The strain of Escherichia that is a common food pathogen, E. coli O157:H7, however can not ferment sorbitol. It will grow similar to other E. coli, but not change the agar color. Is sorbitol in nutrient agar a selective, differential or enrichment media?​

Select all of the pathways that can lead to pore production in a microbial cell.   A. Alternative   B. Lectin   C. Classical

explain how bacteria can develop resistance to chemical disinfectants

The bacterium that causes Hansen’s disease (leprosy), Mycobacterium leprae, infects mostly the extremities of the body: hand, feet, and nose. Would this bacteria’s optimum temperature of growth be above or below the core temperature of the human body?