What are the external influences that may affect the genetic make-up of a bacterial cell?

External influences that can affect the genetic makeup of a bacterial cell include: 1. Horizontal gene transfer: Bacteria can acquire new genes through conjugation (direct DNA transfer between bacteria), transduction (gene transfer via bacteriophages), and transformation (uptake of free DNA from the environment). 2. Mutations: Spontaneous changes in the bacterial DNA can lead to genetic variation. 3. Environmental stress: Changes in environmental factors like temperature, radiation, or nutrient availability can induce stress responses that lead to genetic changes, including the formation of endospores.