Sunny Wong, Ph.D., Associate Professor, Department of Dermatology, University of Michigan Medical School
Hair on your skin or head is produced by hair follicles, dynamic organs that are made up of about 20 different cell types, each with specific functions. This image shows two hair follicles of a mouse, viewed from below the skin. The actual hair shaft ("hair”) is hidden from view, inside of the follicle; it projects up and into the background of the photo. The cloud-like structures in the middle of the follicles are sebaceous glands, which secrete oils onto the surface of the skin to lubricate it and make it waterproof. Alopecia, or hair loss (e.g., as in male pattern baldness) is associated with reduction in size of the existing hair follicles. A common treatment is transplantation of healthy hair follicles into the balding area.