What is the basic definition of a gland in anatomy?

Glands are specialized epithelial cells that produce and release secretions. They can function as single cells (e.g., goblet cells) or in clusters, and are classified as exocrine (with ducts) or endocrine (ductless).

What are the main structural types of exocrine glands?

Exocrine glands are classified by duct branching (simple or compound) and secretory shape (tubular, acinar, or tubulo-acinar). Examples include intestinal glands (simple tubular) and salivary glands (compound acinar).

How do exocrine glands differ in their mode of secretion?

Exocrine glands secrete in three ways: merocrine (by exocytosis, like salivary glands), apocrine (apical part pinches off, like mammary glands), and holocrine (entire cell disintegrates, like sebaceous glands).

What are the different types of secretions produced by exocrine glands?

Exocrine gland secretions include mucous (thick and viscous, like sublingual glands), serous (watery and enzyme-rich, like parotid glands), seromucous (mixed, like submandibular glands), and cellular (cells as secretions, like testis or ovary).

How are endocrine glands structured and what are examples?

Endocrine glands are ductless and release hormones into blood. They are structured as cord and clump type (e.g., adrenal and pituitary glands) or follicular type (e.g., thyroid gland).

What is the difference between unicellular and multicellular glands?

Unicellular glands are single secretory cells, like goblet cells in respiratory or intestinal epithelium. Multicellular glands are clusters derived from surface epithelium, which can be exocrine (with ducts) or endocrine (ductless).

Glands – Exocrine vs Endocrine & Secretion Types