<Li> Apocrine secretion--a portion of the cell membrane that contains the excretion buds off . </Li> <Li> Holocrine secretion--the entire cell disintegrates to excrete its substance; for example, sebaceous glands of the skin and nose . </Li> <Ul> <Li> Serous cells secrete proteins, often enzymes . Examples include gastric chief cells and Paneth cells </Li> <Li> Mucous cells secrete mucus . Examples include Brunner's glands, esophageal glands, and pyloric glands </Li> <Li> Mixed glands secrete both protein and mucus . Examples include the salivary glands: although the parotid gland 20% is predominantly serous, the sublingual gland 5% mainly mucous gland, and the submandibular gland 70% is a mixed, mainly serous gland . </Li> <Li> Sebaceous glands secrete Sebum, a lipid product . These glands are also known as oil glands, e.g. Fordyce spots and Meibomian glands . </Li> </Ul> <Li> Serous cells secrete proteins, often enzymes . Examples include gastric chief cells and Paneth cells </Li>

What are the structural and functional differences between an endocrine gland and an exocrine gland