What is the primary secretion of sebaceous glands?

Sebaceous glands primarily secrete sebum, which is an oily substance that plays a vital role in maintaining healthy skin and hair. Sebum helps to moisturize the skin and provides a protective barrier, preventing the loss of moisture and protecting against harmful microorganisms. This secretion is crucial for maintaining the skin's integrity and overall health.

Perspiration is produced by sweat glands, which serve a different function related to thermoregulation and waste removal. Cerumen, or earwax, is secreted by ceruminous glands found in the ear canal, which also differs significantly in purpose and composition. Oil from the skin could imply a general description of sebum, but it is broader and less accurate than specifying 'sebum' as the specific secretion produced by sebaceous glands. Therefore, identifying sebum as the primary secretion aligns precisely with its defined role in skin physiology.