What describes the structures found in hair follicles that contribute to hair formation?

The correct answer highlights the role of dead cells in the structure of hair follicles contributing to hair formation. Hair itself is primarily composed of a protein called keratin, which is produced by living cells in the hair follicle. However, as hair grows and moves upward through the follicle, it becomes keratinized, leading to the formation of dead, packed cells that form the visible shaft of the hair. These dead cells are tightly packed together, providing strength and structure.

While there are living cells present in the hair bulb that contribute to hair growth, once the hair emerges from the scalp, it is made up of these dead keratinized cells. Understanding this distinction is crucial, as it highlights the transition from living cellular activity at the base of the follicle to the dead, structured material that makes up the hair we see.