Integumentary System Overview

The largest organ in the human body, composed of the epidermis and dermis.

The outermost layer of the skin, composed of stratified squamous epithelial cells.

The inner layer of the skin, containing dense irregular connective tissue and areolar tissue.

The supportive layer beneath the skin, composed of loose areolar and adipose tissue, responsible for connecting the skin to the underlying fascia.

The process by which dead cells from the epidermis are shed.

A tough protein found in skin, hair, and nails, providing protection and water resistance.

The process of the skin producing melanin, a pigment that contributes to skin color and protects from UV radiation.

The process by which the body regulates temperature using mechanisms like sweating and blood vessel constriction/dilation.

The deepest layer of the epidermis, containing stem cells that produce keratinocytes, as well as Merkel cells and melanocytes.

The layer of the epidermis where keratin synthesis begins. It's characterized by spiny-shaped cells.

The layer of the epidermis containing cells that produce keratin and keratohyalin. Cells flatten and die in this layer.

A translucent layer of the epidermis found only in the palms, soles, and digits. It contains flattened, dead cells packed with eleidin.

The outermost layer of the epidermis, consisting of flattened, dead cells packed with keratin. It's the main barrier against microbes and water loss.

The process by which the hair shaft grows from the root of the follicle outwards.

The active growth phase of hair during which cells at the hair root divide quickly.

The transition phase between the anagen and telogen phases where the hair follicle regresses.

The resting phase of hair growth when the follicle is inactive and no new growth occurs.

A gland located in the dermis that secretes sweat via exocytosis into a duct that exits the skin via a sweat pore.

A gland located in the dermis that secretes a cloudy, sticky, and odorous secretion into a hair follicle.

A gland located in the dermis that secretes sebum (oil) into a hair follicle.

A type of exocytosis that releases a product from a cell without loss of cellular membrane.

The process by which melanosomes travel further up the epithelial layers in darker skin, resulting in increased pigmentation.

An orange-yellow pigment found in skin, especially in the stratum corneum. It can be converted into vitamin A.

The superficial layer of the dermis, composed of loose areolar connective tissue. It forms dermal papillae and contains various cells and structures.

The deeper layer of the dermis, composed of dense irregular connective tissue. It houses hair follicles, glands, vessels, and nerve fibers.

A waxy substance produced by the sebaceous glands, which lubricates the skin, prevents water loss, and has antibacterial properties.

The protective layer of the skin, composed of dead keratinocytes, forms at the tips of fingers and toes.

The area at the base of the nail that's slightly off-white and where new nail growth begins.

The area of the skin that extends over the nail body, preventing bacteria from entering.

Lines on the skin that indicate the direction of underlying collagen and elastin fibers.

A genetic condition characterized by a lack of melanin production, leading to pale skin, hair, and eyes.

A condition characterized by patches of lost pigmentation in the skin, appearing as white or light areas.

The most common type of skin cancer, arising from mutations in the stratum germinativum (base layer of the epidermis). It usually occurs in areas exposed to UV radiation and rarely spreads.

The second most common type of skin cancer, originating from mutations in the stratum spinosum (spiny layer of the epidermis). It's not typically life-threatening, but requires treatment to prevent spreading.

The least common but most aggressive form of skin cancer. It develops from cancerous melanocytes, the cells that produce melanin. It can spread rapidly through the lymph system, requiring early detection and treatment.

A skin wound where the surface remains intact but underlying tissues are damaged. Examples include bruises and stage 1 pressure ulcers.

A skin wound where the surface is broken and underlying tissues are exposed. Examples include cuts, stab wounds, and scrapes.

The process of wound healing where wound edges are brought together for faster closure and scar formation. This is often used for clean surgical wounds.

The process of wound healing where wound edges cannot be brought together, requiring healing from the bottom up. This leads to more scarring and takes longer.

The process of wound healing that combines aspects of both primary and secondary intention. It involves initial cleaning, then delayed closure after infection risk is reduced.