Ch. 7.3 Integumentary System Key Terms
Albino
A person with a congenital disorder (albinism) characterized by the partial or total absence of pigment (melanin) in the skin, hair, and eyes.
Alopecia
Partial or complete loss of hair; baldness
Constrict
To become narrower (e.g., blood vessels to reduce blood flow and conserve heat—vasoconstriction)
Crusts
A dried patch of exudate (serum, pus, or blood) over a wound or skin lesion; a scab.
Cyanosis
A bluish or purplish discoloration of the skin due to a lack of adequate oxygen in the blood
Cyst
A closed sac or capsule, typically filled with fluid, air, or semi-solid material, that forms abnormally in any body tissue
Dermis
The layer of skin directly below the epidermis. It contains blood vessels, nerves, hair follicles, and glands
Dilate
To become wider or larger (e.g., blood vessels to increase blood flow and release heat—vasodilation)
Epidermis
The outermost layer of skin that provides a waterproof barrier and creates skin tone.
Erythema
Redness of the skin, often a sign of inflammation or irritation, caused by increased blood flow to capillaries.
Hypodermis
Also known as the subcutaneous layer, it is the layer of loose connective tissue and fat (adipose tissue) located beneath the dermis
Integumentary system
The body system comprising the skin, hair, nails, and associated glands
Jaundice
A medical condition characterized by a yellowing of the skin and whites of the eyes, typically due to excessive bilirubin
Macules
A small, discolored patch or spot on the skin that is flat and not raised
Melanin
A dark brown or black pigment that occurs naturally in the skin and is responsible for color and protection against UV radiation
Papules
A small, solid, raised lesion on the skin
Pustules
A small, raised area of the skin that contains pus
Sebaceous glands
Glands that secrete sebum (oil) into hair follicles to lubricate the skin and hair.
Subcutaneous
Pertaining to the tissue layer under the skin (the hypodermis).
Sudoriferous glands
Commonly known as sweat glands, they produce and secrete sweat to help regulate body temperature
Ulcer
An open sore on the skin or mucous membrane that results from injury or poor circulation and fails to heal
Vesicles
A small, fluid-filled blister or sac on the skin (e.g., in chickenpox)
Wheals
A raised, red, itchy area of skin, often temporary, that results from an allergic reaction or insect bite