Answer:
Cell Envelope - The chemically complex external covering of the majority of bacteria. Lies outside of the cytoplasm. Composed of two or three basic layers: the cell wall (peptidoglycan), the cell membrane, and, in some bacteria, the outer membrane. Acts as a single protective unit.
Explanation:
Answer:
Genetic variation is caused by:
mutation
random mating between organisms
random fertilization
crossing over (or recombination) between
chromatids of homologous chromosomes during
meiosis