You have studied some microbes that cause disease. Understanding how microbes grow and multiply is important when identifying and dealing with transmission of infection. This week will focus on bacteria. Think about what you already know about bacteria, how they are structured, function, and replicate. Discuss what you need to know in order to deal in the field with bacterial outbreaks.

Structure: unicellular organisms (single-celled), no nucleus or membrane-bound organelles, genetic material usually composed of a single circular bacterial chromosome coiled up in a region of the cytoplasm

Function: metabolic functions are carried out in the bacterial cytoplasm

Replication: generally asexual (binary fission)

Explanation:

Bacteria are prokaryotic organisms, i.e., unicellular organisms that do not have a cell nucleus nor any membrane-bound organelles . Generally, the genetic material is composed of a single DNA circular molecule (bacterial chromosome), which is localized in a specific region of the cytoplasm (nucleoid region). Prokaryotic cells are usually smaller than eukaryotic cells (0.1 - 5 μm in size). In bacteria, metabolic functions (i.e., growth and reproduction) occur in the cytoplasm. The most important process of reproduction in bacteria is binary fission, a form of asexual reproduction where a single bacterial cell divides into two. Bacteria can also exchange genetic material by sexual reproduction mechanisms (i.e., conjugation, transformation and transduction). The main strategy to prevent outbreaks caused by bacteria is to know the conditions where they grow and reproduce. For example, Salmonella is a genus of infectious bacteria that may cause an outbreak. Salmonella infection may be prevented by eliminating conditions where they can multiply. Measures to prevent Salmonella outbreaks include cook food thoroughly (do not eat raw eggs or raw beef), refrigerate foods, wash hands, etc.

"griffith's experiment discovering the "transforming principle" in pneumococcus bacteria. griffith's experiment, reported in 1928 by frederick griffith, was the first experiment suggesting that bacteria are capable of transferring genetic information through a process known as transformation." - griffith's experiment.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".