What is a thick, club-shaped structure made from epithelial cells that surrounds the papilla?

The thick, club-shaped structure made from epithelial cells that surrounds the papilla is known as the hair bulb. The hair bulb is located at the base of the hair follicle and contains the living part of the hair. It is where the hair growth occurs, with cells multiplying and keratinizing to form the hair shaft that we see above the skin surface.

The hair bulb is crucial for hair production because it houses the hair matrix, where new hair cells are generated and pushed upward. This area also plays a vital role in the overall health of the hair, as it relies on the surrounding papilla for nutrients and support. This relationship between the hair bulb and the papilla is essential for proper hair growth.

In contrast, the hair papilla is a small, nipple-like structure that contains blood vessels and connective tissue, providing the necessary nutrients to the hair bulb. Hair follicles refer to the entire sheath that includes the hair bulb, papilla, and surrounding structures. The hair shaft is the visible part of the hair that extends out from the skin but does not include the bulb or papilla itself. Understanding these structures and their functions aids in comprehending the complexities of hair growth and overall hair health.