Sebaceous glands, also known as oil glands, secrete oil. These glands are found throughout the body, most prominently on the face, scalp, and upper chest. Their primary function is to produce sebum, an oily substance that lubricates the skin and hair, preventing dryness and cracking.
Understanding Sebaceous Glands
- Function: Sebaceous glands secrete sebum, an oily substance that moisturizes and protects the skin and hair. Cleveland Clinic explains that sebum is secreted through hair follicles.
- Location: They're located in the dermis, the middle layer of skin. Merck Manual notes their presence alongside hair follicles, sweat glands, and blood vessels within the dermis. They're particularly abundant on the face, scalp, and upper chest.
- Secretion Type: They are holocrine glands, meaning they release their secretions by rupturing the cells that produce the sebum. Quizlet confirms that sebum is the oil secreted. This process of cell rupture and secretion is part of their normal function.
- Clinical Significance: Conditions like acne are linked to the dysfunction of sebaceous glands. Johns Hopkins Medicine describes acne as a disorder of hair follicles and oil glands (sebaceous glands). The overproduction or blockage of sebum can lead to acne breakouts. Additionally, aging affects sebaceous gland function resulting in drier skin. MedlinePlus mentions decreased oil production with age.
- Other Examples: Beyond the skin, other glands also produce oils with important functions. For example, Meibomian glands in the eyelids secrete oil to lubricate the eyes. American Academy of Ophthalmology details their role in eye lubrication. Animals also possess oil-secreting glands; for instance, otters have skin glands that release oil for waterproofing their fur. Minnesota DNR mentions this example.
