Which of the following glands are classified as exocrine glands in the integumentary system?

Exocrine glands are characterized by their ability to secrete substances through ducts to an external surface or into body cavities. In the integumentary system, sweat glands and sebaceous glands fit this definition perfectly. Sweat glands produce sweat to help regulate body temperature and eliminate waste, while sebaceous glands secrete sebum, which lubricates and protects the skin and hair. Both types of glands play essential roles in maintaining homeostasis within the integumentary system.

In contrast, the other glands mentioned do not qualify as exocrine. Adrenal glands and thyroid glands are endocrine glands, meaning they secrete hormones directly into the bloodstream rather than through ducts. The pineal gland also functions as an endocrine gland, primarily producing the hormone melatonin and regulating sleep patterns. Understanding the distinction between exocrine and endocrine glands is crucial to identifying their functions and locations within different body systems.