Key words
Albino
A person with an absence of color pigments. An albino’s skin has a pinkish tint, the hair is pale yellow or white, and the eyes are red and very sensitive to light.
Cyst
A closed sac with a distinct membrane that develops abnormally in a body structure; usually filled with a semisolid material.
Hypodermis (Subcutaneous fascia)
The innermost layer of skin made of elastic and fibrous connective tissue and adipose (fatty) tissue; connects skin to underlying muscles.
Papules
Small, firm, raised lesions less than 0.5 cm in diameter (such as pimples).
Ulcer
A deep loss of skin surface that may extend into the dermis; may cause periodic bleeding and scarring.
Alopecia
Baldness; a loss of hair on the scalp.
Dermis
Also called corium or “true skin.” Contains blood vessels, nerves, lymph vessels, sweat and oil glands, involuntary muscle, and hair follicles.
Integumentary system
The skin; a system that covers over 3,000 square inches of surface area and accounts for about 15% of total body weight. Includes skin, hair, nails, and glands.
Pustules
Pus-filled lesions such as those seen in acne or pimples.
Vesicles
Small blisters or fluid-filled sacs less than 0.5 cm in diameter (seen in chickenpox).
Constrict
To get smaller; when blood vessels constrict, heat is retained in the body.
Dilate
To get larger; when blood vessels dilate, excess heat escapes from the body.
Jaundice
A yellow discoloration of the skin caused by the presence of bile in the blood due to liver or gallbladder disease.
Sebaceous glands
Oil glands that usually open onto hair follicles. They produce sebum, which keeps skin and hair from becoming dry and brittle.
Wheals
Itchy, elevated areas with an irregular shape; examples are hives or insect bites.
Crusts
Areas of dried pus and blood, commonly called scabs.
Epidermis
The outermost layer of skin made of five smaller layers, containing no blood vessels or nerve cells.
Macules
Flat, discolored lesions less than 1 cm in diameter (e.g., freckles).
Subcutaneous
Located or applied under the skin; referring to the subcutaneous fascia layer containing fat tissue.
Cyanosis
A bluish discoloration of the skin caused by insufficient oxygen.
Erythema
A reddish color of the skin caused by burns or congestion of blood in the vessels.
Melanin
A brownish-black pigment produced by melanocytes in the epidermis that determines skin color.
Sudoriferous glands
Sweat glands that extend through the dermis and open on the skin’s surface.