The Integumentary System

Integumentary System

The system of the body that consists of the skin and its accessory structures like hair, glands, and nails.

Epidermis

The outermost layer of the skin, composed of epithelial tissue.

Dermis

The layer of the skin beneath the epidermis, made of dense connective tissue.

Subcutaneous Tissue

Also known as hypodermis, it is the layer of loose connective tissue beneath the skin that connects it to underlying bone and muscle.

Keratinization

The process in which cells in the epidermis fill with the protein keratin as they move towards the surface.

Stratum Basale

The deepest layer of the epidermis, consisting of cuboidal or columnar cells that undergo mitotic divisions.

Stratum Corneum

The most superficial layer of the epidermis, consisting of dead squamous cells filled with keratin.

Melanin

The primary pigment responsible for skin, hair, and eye color, providing protection against UV light.

Melanocytes

Cells located between the stratum basale and stratum spinosum that produce melanin.

Dermal Papillae

Projections in the upper dermis that extend toward the epidermis and contain numerous blood vessels.

Cleavage Lines

Lines in the skin determined by the orientation of collagen fibers, representing areas of greater resistance to stretch.

Stretch Marks

Visible lines that develop on the skin when the dermis is damaged due to overstretching.

Intradermal Injections

Injections delivered by inserting a small needle at a shallow angle into the dermis.

Subcutaneous Injections

Injections delivered by inserting a short needle into the adipose tissue of the subcutaneous layer.

Intramuscular Injections

Injections delivered by inserting a long needle at a 90-degree angle into deep muscle tissue below the subcutaneous layer.

Albinism

A genetic condition causing a lack of melanin, resulting in fair skin, white hair, and unpigmented irises.

Cyanosis

A bluish skin color caused by reduced blood oxygen content.

Carotene

A yellow pigment from plants that can accumulate in the skin, resulting in a yellowish appearance.

Anterior

Referring to the front of the body or an organ.

Posterior

Referring to the back of the body or an organ.

Body fat percentage

The percentage of fat in the body, which varies among individuals and is generally higher in females than males.

Acceptable body fat percentages

The range of body fat percentages considered healthy, which is 21% to 30% for females and 13% to 25% for males.

Accessory skin structures

Structures attached to or embedded into the skin, including hair, glands, and nails.

Hair follicle

An extension of the epidermis that reaches deep into the dermis and from which each hair emerges.

Hair shaft

The stem of the hair that extends above the skin's surface.

Hair bulb

The part of the hair follicle where hair production occurs, resting on the hair papilla.

Hair growth cycle

The cycle of growth and rest that hair goes through, with new hairs forming during the growth stage and old hairs falling out during the new growth stage.

Pattern baldness

Permanent hair loss caused by male sex hormones affecting hair follicles in individuals with a genetic predisposition.

Nail matrix

The part of the nail that extends from the nail root and attaches to the underlying nail bed, responsible for nail production.

Lunula

A whitish crescent-shaped area at the base of the nail, visible as a small portion of the nail matrix.

Sweat glands

Glands that produce sweat, which contains small amounts of waste products like urea, uric acid, and ammonia.

Cyanosis

A bluish skin color that indicates impaired circulatory or respiratory function.

Jaundice

A yellowish skin color that suggests liver damage, such as in viral hepatitis.

Rashes and lesions

Symptoms of underlying issues, such as scarlet fever, allergic reactions, or infections.

Nutritional deficiencies

Deficiencies in nutrients that can affect the skin, such as excess keratin production in vitamin A deficiency and flat or spoon-shaped nails in iron-deficiency anemia.

Burns

Injuries to the skin categorized as partial-thickness burns (damaging the epidermis or epidermis and dermis) or full-thickness burns (destroying the epidermis, dermis, and underlying tissues).

Psoriasis

A chronic skin disease characterized by a thicker than normal epidermal layer that produces large, silvery scales.

Impetigo

Bacterial infection causing small blisters containing pus that easily rupture to form a thick, yellowish crust.

Decubitus ulcers (bedsores)

Ulcers that develop in people who are bedridden or confined to a wheelchair due to tissue compression and reduced circulation.

Rubeola (measles)

Viral infection causing skin lesions, contracted through the respiratory tract.

Rubella (German measles)

Viral infection causing skin lesions, usually mild and contracted through the respiratory tract.

Chickenpox

Viral infection causing skin lesions, usually mild and contracted through the respiratory tract.

Shingles

Painful skin lesions that can recur when the dormant chickenpox virus is activated.

Cold sores (fever blisters)

Skin lesions caused by the herpes simplex I virus, transmitted orally or through respiratory routes.