What structure gives rise to the stem cells from which a hair develops?

• A. Hair follicle
• B. Dermal papilla
• C. Sebaceous gland
• D. Epidermis

Answer: (A)

Verified step by step guidance

1. Understand the anatomy of a hair follicle: A hair follicle is a complex structure in the skin from which hair grows. It includes several components such as the dermal papilla, sebaceous gland, and the epidermis.
2. Identify the role of the dermal papilla: The dermal papilla is a small, nipple-like projection at the base of the hair follicle. It plays a crucial role in hair growth by providing nutrients and signals to the hair matrix cells.
3. Examine the function of the hair matrix: The hair matrix is located just above the dermal papilla and contains rapidly dividing cells. These cells are responsible for producing the hair shaft and are considered the stem cells for hair development.
4. Consider the role of the sebaceous gland: The sebaceous gland is associated with the hair follicle and secretes sebum, an oily substance that lubricates the hair and skin. However, it does not contribute to the formation of hair stem cells.
5. Analyze the contribution of the epidermis: The epidermis is the outermost layer of the skin, providing a protective barrier. While it is involved in skin regeneration, it is not directly responsible for the stem cells that develop into hair.