Final answer:
The Stratum Granulosum consists of typically three to five cell layers where keratinocytes produce keratin and keratohyalin, giving the layer a grainy appearance. As cells die, they leave behind materials forming the uppermost skin layers and accessory structures.
Step-by-step explanation:
The Stratum Granulosum is an essential layer of the epidermis in which keratinocytes undergo significant changes, creating a grainy appearance. This layer consists typically of three to five layers of flattened cells. The keratinocytes generate large amounts of keratin and keratohyalin, with the latter accumulating as lamellar granules. These proteins contribute to the grainy texture and are critical in the formation of the stratum lucidum, stratum corneum, and accessory structures such as hair and nails. The process involves the dissolution of cell nuclei and organelles as the cells in the stratum granulosum die, leaving behind cell membranes enriched with keratin and keratohyalin.