Final answer:
The nail matrix is the deep pocket-like area that holds the root and the matrix of the nail, essential for nail growth and contains stem cells responsible for producing keratinocytes.
Step-by-step explanation:
The deep pocket-like area that holds the root and the matrix of the nail is known as the nail matrix. The nail matrix is a layer of deep, living epidermal tissue located at the proximal end of a nail. It surrounds the nail root and is essential for nail growth as it contains stem cells that divide to form keratinocytes, which in turn produce keratin, the main component of the nail.
The nail root is the part of the nail that is lodged deep in the epidermis from where the nail grows. The nail plate, which is the hard and translucent part of the nail, is formed by the nail matrix and grows out over the nail bed, which appears pink due to the blood vessels present in the underlying dermis.
The eponychium, also known as the cuticle, is another structure related to the nail anatomy. It is the fold of epithelium that extends over the nail bed at the proximal end, and alongside resides the nail fold, which helps hold the nail body in place.