2C notes (integument, epidermis)

These flashcards cover key concepts related to the integumentary system, including its structure, functions, and associated terminology.

Integumentary System

Forms a protective barrier for the body, includes the epidermis, dermis, and hypodermis.

Epidermis

Outer layer of skin composed of stratified squamous epithelium, primarily containing keratinocytes.

Dermis

Deep layer of skin located beneath the epidermis; composed of dense irregular connective tissue providing strength and flexibility.

Hypodermis (subcutaneous layer)

Layer below the dermis composed of areolar and adipose connective tissue; anchors skin and provides insulation.

Keratinocytes

Most abundant cell type in the epidermis, their shape changes as they move upward through the skin layers.

Stratum basale

Deepest epidermal layer with a single layer of cuboidal/columnar cells, including keratinocytes and melanocytes.

Melanocytes

Cells in the stratum basale that produce melanin for UV protection.

Types of melanin

Pheomelanin (yellow-red) and Eumelanin (brown-black).

Epidermal dendritic (Langerhans) cells

Mobile immune cells in the stratum spinosum and granulosum that respond to pathogens.

Keratinization

Process where keratinocytes fill with keratin, die, and form protective layers.

Stratum corneum

Outermost layer of the skin consisting of dead, interlocking, keratinized cells; serves as a barrier.

Friction ridges

Unique patterns on fingertips, responsible for fingerprints.

Vitamin D precursor

7-dehydrocholesterol in the skin converts to previtamin D under UVB rays, leading to vitamin D3.

Hemangiomas

Blood vessel overgrowth resulting in skin markings.

Carotene

Yellow-orange pigment derived from diet, contributing to skin color.