Dermatology
The medical branch of science that deals with the study of skin- it's nature, structure, functions, diseases, and treatments
The largest organ of the body
Skin
Healthy skin is...
Slightly moist, soft, and flexible with a texture that is smooth and fine grained. Slightly acidic, good immune response.
Skin appendages include
Hair, nails, sweat, and oil glands
What areas have the thickest and thinnest skin?
Eyelids have the thinnest, soles have the thickest
Calluses are caused by:
Continued pressure that causes thickened areas.
What are the two areas that the skin is divided into?
Dermis and epidermis or papillary/superficial, and reticular or deeper.
Epidermis
Outermost layer of skin, also called the cuticle. Has no blood vessels, but many small nerve endings.
Esthetician
A specialist in the cleansing, preservation of health, and beautification of the skin and body
Name the layers of the epidermis
Basal cell layer (stratum germinativum), stratum granulosum (granular layer), stratum lucidum (transparent layer), stratum corneum (horny layer)
What is the underlying or inner layer of skin?
The dermis, or derma, or corium
What are Melanocytes?
Special cells that produce dark skin pigment called melanin that protects the skin from the sun/ UV rays.
What does the Stratum granulosum do?
It is the granular layer that consists of almost dead skin that are almost dead and will be pushed to the surface to replace shed skin.
What does the stratum germinativum (basal cell layer) do?
It is the deepest layer of the epidermis and is the live layer that produces new cells. It also contains melanocytes.
What does the stratum lucidum do?
It is the transparent layer just under the skins surface, it consists of small cells through which light can pass.
What is the stratum corneum (horny layer)?
This is the layer we see when we look at the skin, and the layer that the practitioner works on. It's scale like cells are continually being shed. These cells are made of keratin, a fiber protein.
What does the dermis do?
It is the true skin, and is under the epidermis. It is a highly sensitive layer of connective tissue and is 25 times thicker than the epidermis. It contains blood vessels, lymph vessels, nerves, sweat glands, oil glands, hair follicles, and arrector pilli
What are arrector pilli?
The small muscles that work in connection with hair follicles to cause goose bumps.
What is the place called where the epidermis and papillary levels are joined called?
Epidermal junction
What are the two levels of the dermis called?
Papillary and reticular
What does the papillary layer do?
It is the topmost layer of the dermis directly below the epidermis, and holds dermal papillae, and tactile corpuscles (nerve endings)
What is the reticular layer?
The deeper layer of the skin that supplies the skin with oxygen and nutrients. (a reticule is a suitcase- this layer carries fat cells, and various glands, follicles, and vessels)
Which layer of the skin houses the nerve ending that provide sense of touch?
The papillary layer
What is melanin?
Tiny grains of pigmentation deposited into the basal cell layer of the epidermis, and the papillary layers of the dermis.
What are the two types of melanin?
Pheomelanin (red to yellow) and eumelanin (dark brown to black)
What is collagen?
A fibrous protein that gives the skin form and strength.
What is elastin?
A protein base that is similar to collagen and forms elastic tissue. It is interwoven with collagen.
What are Sudoriferous glands?
Sweat glands that are ducts that extract material from the blood to form sweat.
What are sebaceous glands?
Oil glands that are ducts that extract material from the blood to create oil.
What do sebaceous glands do?
They are sacs that open into the hair follicle and excrete sebum, a fatty and oily secretion that lubricates the skin and preserves the softness of the hair.
What is a comedone?
Hardened sebum that hardens and clogs the skin.
Name the functions of the skin.
Protection, sensation, heat regulation, excretion, secretion, and absorption.
What is retin-a?
Vitamin A, and antioxidant that can prevent cancer, improve skin elasticity and thickness, and called retin a in it's topical form.
What part of the body weight is water?
50-70 percent