The type of cells that form the strata in the epidermis are

The type of cells that forms the stratum in the epidermis are basal cells.

Explanation:

Basal cells have the shape of cuboidal stem cell which forms different stratum in the epidermis. There are mainly five stratum layers in the epidermis: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum. All these stratum layers have the basic basal cells as its foundation. These basal cells have a special ability to continuously divide and form new cells forming the skin.