Cutaway illustration of the internal structure of a typical bacterial cell. This example is of a capsulated bacterium; the capsule (light green) forms the outer of 3 layers, covering the cell wall (dark green) and the inner cytoplasmic membrane. Bacteria lack a nuclear membrane & hence a well-defined nucleus. Here, the nuclear body is represented as the blue, spherical feature towards the top of the cell. An invagination into the cytoplasmic membrane is featured at lower right. Growing bacteria contain numerous ribosomes (red spheres) within their cytoplasm, that are involved in the assembly of proteins. Other inclusions act as reserves of energy & nutrients.