Sebaceous gland Sebaceous gland Sebaceous glands are microscopic exocrine glands in the skin that secrete an oily or waxy matter, called sebum, to lubricate and waterproof the skin and hair of mammals. In humans, they occur in the greatest number on the face and scalp, but also on all parts of the skin except the palms of the hands and soles of the feet. The type of secretion of the sebaceous glands is referred to as holocrine. In the eyelids, meibomian glands, also called tarsal glands, are a type of sebaceous gland that secrete a special type of sebum into tears. Fordyce
Olfactory glands of the secretions from olfactory glands is unclear, but there is evidence that they produce odorant binding protein. Olfactory glands Olfactory glands, also known as Bowman's glands are situated in the olfactory mucosa, beneath the olfactory epithelium, in the lamina propria, a connective tissue also containing fibroblasts, blood vessels, and bundles of fine axons from the olfactory neurons. An olfactory gland consists of an acinus in the lamina propria and a secretory duct going out through the olfactory epithelium. Electron microscopy studies show that olfactory glands contain cells with large secretory vesicles. Olfactory glands secrete the gel-forming mucin MUC5AC(UniProtKB: P98088).