The epidermis is the outermost layer of the skin, which acts as the body’s major barrier against an inhospitable environment. The epidermis is avascular, (without blood) and composed for four cell types:
Keratinocytes, Melanocytes, Langerhan cells, and Merkel cell.
Keratinocytes accounts for 95%, while melanocytes make up less than 2%. The epidermis can be further subdivided into the following strata: corneum, lucidum (palms and bottoms of feet), granulosum, spinosum, & basale.
Cells are formed through mitosis at the basale layer. Every 27 days, these cells migrate towards the surface, die and harden (keratinized).
This keratinized layer of skin is responsible for keeping water in the body and keeping other harmful chemicals and pathogens out, making skin a natural barrier to infection.
Melanocytes produce a protein called melanin. In humans, melanin is the primary determinant of skin color and is also found in hair and eyes. Melanin is found in the plant, animal, and protozoa kingdoms, where it predominantly acts as a pigment. The most common form of biological melanin in the epidermis is eumelanin, a brown-black polymer.
Another common form of melanin is pheomelanin, a red-brown polymer largely respon- sible for red hair and freckles.
All humans have the same number of melanocytes, but some produce more eumelanin and pheomelanin than others.
People with dark skin and hair produce more eumelanin, whereas blondes produce very little eumelanin or pheomelanin.
I just wanted to thank you for an incredible experience at the open house and intro class. I have visited several schools in my quest over the past year to find a place to continue my journey into massage therapy, and I have never experienced such positive energy from both the staff and students. To put it quite simply I felt at home and welcomed, thank you. I have found where I choose to follow this path.
