Glands are classified based on their method of secretion and cellular arrangement. The primary classifications are: - Exocrine Glands: These glands secrete their products into ducts that lead to external environments or body cavities. Examples include sweat glands and salivary glands. - Endocrine Glands: These glands release hormones directly into the bloodstream. Examples include the thyroid gland and adrenal glands.
