From which type of gland does vellus hair originate?

Vellus hair originates from sebaceous glands. These glands are associated with hair follicles and play a crucial role in maintaining the health of the hair and scalp. Vellus hair is fine, soft, and unpigmented, and it is commonly found on various parts of the body, providing insulation and contributing to skin hydration by facilitating the function of the sebaceous glands.

Sebaceous glands secrete an oily substance called sebum, which coats the hair and skin, helping to keep them moisturized and protected. This relationship between the sebaceous glands and vellus hair is essential for its growth and maintenance, indicating the significance of these glands in hair physiology.

The other glands listed do not directly associate with the origin or development of vellus hair. For example, apocrine glands are associated more with thicker, scented hair and are often found in areas like the armpits, while eccrine glands are primarily involved in thermoregulation through sweat production, not hair. Adenoid glands are not related to hair follicles or the development of hair.