Skin and Accessory Structures

Vocabulary flashcards covering key terms related to skin anatomy, accessory structures, and related physiological responses from the lecture notes.

Stratum Lucidum

A layer of dead, daily, interlocking, keratinized cells found only in thick skin (palms and soles), providing an extra layer of protection.

Thick Skin

Skin found on the palms of the hand and soles of the feet, characterized by the presence of the stratum lucidum.

Stratum Granulosum

A layer consisting of three to five layers of keratinocytes that are actively undergoing keratinization, meaning cells are dying and filling with keratin filament.

Keratinization

The process where cells fill with keratin filaments, leading to their breakdown and the formation of a tough, protective keratinized layer.

Keratinocytes

The most abundant cells in the epidermis, responsible for producing keratin protein and making the skin water-resistant; stem cells divide to continuously replace them.

Thin Skin

Skin that lacks the stratum lucidum, having only four layers in the epidermis, and covers the majority of the body surface.

Dermis

The layer of skin adjacent to the stratum basale.

Reticular Layer

The deeper and thicker layer of the dermis that connects to the underlying subcutaneous layer.

Papillary Layer

The layer of the dermis located directly below the epidermis (also referred to as the capillary layer).

Lanula

The proximal, whitish, crescent-shaped area of the nail body, caused by the thickening of the nail matrix underneath.

Cuticle (Nail)

The fold of skin that extends from the margins of the nail onto the nail body, surrounding the back part of the nail.

Hyponychium

The thickened stratum corneum (skin) located underneath the free edge of the nail.

Nail Bed

The part of the digit that lies directly underneath the nail plate.

Nail Root

The embedded, back part of the nail that lies under the skin, from which the nail constantly grows.

Nail Matrix

The back part of the nail bed responsible for producing the cells that form and push out the nail plate.

Hair Root

The portion of the hair extending from the hair fold to the surface of the skin.

Hair Shaft

The visible portion of the hair that extends beyond the surface of the skin.

Endocrine Gland

A gland that secretes its products directly into the bloodstream.

Pore

The opening of a duct, such as a sweat gland, which is controlled by the nervous system and plays a role in thermal regulation.

Third-Degree Burn

A severe burn that causes damage extending all the way down to the subcutaneous layer.

Smoke Inhalation Response

A protective mechanism where the body closes the throat to prevent breathing in smoke, which can unfortunately lead to suffocation.