Final answer:
The hair papilla is the cone-shaped elevation at the base of the hair follicle that fits into the hair bulb, providing necessary nutrients to the hair. It is surrounded by the hair bulb and hair matrix, which are involved in hair production. The glassy membrane layer is the protective structure that surrounds and connects the follicle to the dermis.
Step-by-step explanation:
The cone-shaped elevation at the base of the follicle that fits into the bulb is known as the hair papilla. This structure is a mass of connective tissue that includes blood capillaries and nerve endings. Its primary role is to provide nourishment to the growing hair follicle. In the context of a hair follicle cross-section, the hair papilla is located at the very base and is surrounded by the hair bulb, which includes a layer of basal cells known as the hair matrix.
The hair matrix is responsible for the production of new hair cells which eventually keratinize and form the hair shaft that grows out of the skin. The growth of hair in the follicle begins in the centre with the differentiation of cells in the hair matrix, leading to the formation of the inner root sheath, while the basal cells at the base of the hair root form the outer root sheath, all of which is surrounded by a protective structure known as the glassy membrane layer which connects to the dermis.