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How do endocrine glands differ from exocrine glands?

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human endocrine system The principal glands of the female and male human endocrine systems.

The primary difference between endocrine and exocrine glands lies in how they transport their secretions throughout the body.

Endocrine glands are ductless glands that secrete substances, known as hormones, directly into the bloodstream. These hormones then travel to specific target tissues to exert their effects. Examples include the pituitary gland, thyroid gland, and adrenal glands.123
Exocrine glands possess secretory ducts through which they discharge their products, such as saliva, sweat, or digestive enzymes, onto an internal or external body surface.124

While many organs function exclusively as one type, some organs serve both roles. The pancreas is the most well-known example of an organ that functions as both an endocrine gland—by secreting hormones like insulin into the blood—and an exocrine gland—by secreting digestive substances through ducts.32