What does SI mean? Definitions for SI Here are all the possible meanings and translations of the word SI.
The 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.ebaceous glands secrete the oily, waxy substance called sebum (Latin: fat, tallow) that is made of triglycerides, wax esters, squalene, and metabolites of fat-producing cells. Sebum waterproofs and lubricates the skin and hair of mammals.
Oil glands, also called as sebaceous glands are so small that they can be only seen under microscope. These are present in the skin and perform the function of secreting oil deposits on the skin hair. This secretion is termed as sebum. The main function of sebum is to protect against germs. But when it is secreted in excess, which could be due to hormonal imbalance or other side effects of medication, it causes acne.