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.
Sweat glands are duct glands found in the skin and responsible for the secretion of sweat, which are watery in nature. The duct of the gland is opened at the skin surface by minute pore. There are two types of sweat glands; eccrine sweat glands and apocrine sweat glands. Eccrine sweat glands secrete thin sweat and are not associated with hairs. Eccrine secretions are crucial for thermo-regulation of animals.