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
Human microbiota type on the human body. A majority of microbes reside on superficial cells on the skin or prefer to associate with glands. These glands such as oil or sweat glands provide the microbes with water, amino acids, and fatty acids. In addition, resident bacteria that associated with oil glands are often Gram-positive and can be pathogenic. A small number of bacteria and fungi are normally present in the conjunctiva. Classes of bacteria include Gram-positive cocci (e.g., "Staphylococcus" and Streptococcus) and Gram-negative rods and cocci (e.g., "Haemophilus" and "Neisseria") are present. Fungal genera include "Candida", "Aspergillus", and "Penicillium". The lachrymal glands