An organism has body cells with 22 chromosome
a body cell prepares for cell division. how many chromosomes does it have at the beginning of prophase?

In the process there are still 22 chromosomes consisting the cell, it divides later at the metaphase.

This cell division is primarily called the mitotic process -mitosis.
Mitosis occurs more in your body since it changes, modifies and requires cell division at maximum rate in many useful situations with the stand to a particular system and organ. Mitosis and meiosis are simply cell division processes that occurs differently, they're characteristically divergent from each other according to their function and structure. Mitosis is the cell division that happens in all cells in the human body except sperm and egg cells. They produce diploid cells. Take for instance your integumentary system, layer of the skin in which your stratum basale always produces new epithelial cells (via mitosis) to take over until the outer layer, called stratum corneum (a continous replaced dead cells in this layer).

They create genetic variations