An Introduction to Bacteria

Question 1

Describe the main structures and functions of a typical bacterial cell

Answer 1

o	Penicillin Binding Proteins
	- Enzymes which synthesise peptidoglycans
o	Peptidoglycans
	- Give the cell strength and shape
	- Carbohydrate polymers cross linked with amino acids
o	Lipopolysaccharide (LPS, endotoxin)
	- Component of Gram Negative cell wall
o	Flagellum
	- Motility
o	Fimbriae
	- Adherence

Question 2

Explain the classification of and nomenclature used for bacterial species.

Answer 2

• The name is based on the genus and the species. - Strains of a species has similar characteristics.
• Typing is used to identify strains.

Question 3

Describe the ways in which bacteria are identified by using particular features of their size, shape, growth requirements and staining characteristics.

Answer 3

o	Gram Staining
	- Positive
	- Negative
o	Shape
	-  Cocci - Spherical
	-  Bacilli – Rod Shaped