A gland that produce and pours its secretion on the surface or into a particular region by means of ducts are called exocrine gland. Modes of secretion of exocrine gland are of three types they are, apocrine glands, holocrine glands, or merocrine glands based on how their products are secreted. Sebaceous gland in the skin, salivary gland in the buccal cavity, bile-producing glands of the liver, sweat gland, gastric gland etc. are examples of exocrine glands.