Mitosis is highly conserved across eukaryotic organisms. Apart from asexual reproduction, state two other roles of mitosis in multicellular organisms.

Many eukaryotic organisms can reproduce both sexually and asexually. Explain why mitosis, and not meiosis, is the cell division mechanism used during asexual reproduction.

Single-celled prokaryotes, such as Escherichia coli, reproduce asexually by binary fission rather than mitosis. Explain why bacteria cannot undergo mitosis.

During meiosis, the independent assortment of chromosomes is a key source of genetic diversity in gametes. The gametes of the garden pea (Pisum sativum) contain $7$ chromosomes. Assuming no crossing over occurs, calculate the number of genetically different gametes that can be produced by an individual pea plant as a result of the independent assortment of chromosomes.

Number of different gametes = ________