GAP Ch5 The Integumentary System

Integumentary System

The organ system that includes the skin, hair, nails, and glands, providing protection and other functions.

Epidermis

The outermost layer of the skin, composed of keratinized stratified squamous epithelium.

Dermis

The deeper layer of skin beneath the epidermis, containing blood vessels, nerves, and connective tissue.

Hypodermis

The layer of tissue beneath the dermis, not technically part of the skin, serving to connect the skin to underlying structures.

Keratinocytes

Cells in the epidermis that produce and store keratin.

Stratum Basale

The deepest layer of the epidermis, containing stem cells that undergo mitosis.

Stratum Spinosum

The layer above the stratum basale, composed of 8-10 layers of keratinocytes that begin keratin synthesis.

Stratum Granulosum

The layer of the epidermis where keratinocytes flatten and produce keratin granules.

Stratum Lucidum

A clear layer of dead keratinized cells found only in thick skin, such as the palms and soles.

Stratum Corneum

The outermost layer of the epidermis, consisting of dead, dry keratinized cells that provide a protective barrier.

Melanin

A pigment produced by melanocytes that gives color to hair and skin and protects against UV radiation.

Melanocytes

Cells in the stratum basale that produce melanin.

Sebum

An oily substance secreted by sebaceous glands that keeps the skin and hair moisturized.

Eccrine Sweat Glands

Sweat glands that are widespread, producing a watery sweat for thermoregulation.

Apocrine Sweat Glands

Sweat glands primarily found in hairy areas, producing thicker sweat that can cause odor due to bacterial decomposition.

Thermoregulation

The process by which the body maintains its internal temperature through sweating and blood flow adjustments.

Touch Corpuscles

Sensory receptors in the skin that respond to light touch, also known as Meissner's corpuscles.

Pacinian Corpuscles

Sensory receptors that detect pressure and vibration, located deeper in the dermis.

Avascular

A term describing tissues that lack blood vessels; in the skin, this refers to the epidermis.

Keratinization

The process by which keratinocytes produce keratin and move towards the skin surface.

Vitamin D Synthesis

The process of forming vitamin D in the skin through exposure to UV radiation.

Cholecalciferol

Also known as vitamin D3, it is synthesized in the skin and needs to be converted to become active.

Calcitriol

The active form of vitamin D, synthesized in the kidneys from calcidiol.

Adipose Tissue

A type of connective tissue that stores fat and provides insulation and cushioning.

Thermal Regulation

The body's ability to regulate temperature through mechanisms like sweating and blood vessel dilation.

Stratum Lucidum

A layer only present in thick skin, providing additional protection.

Pseudoriferous Glands

Another term for sweat glands, responsible for cooling the body.

Meissner’s Corpuscles

Sensory receptors in the papillary layer that detect light touch.

Melanosome

A vesicle that carries melanin from melanocytes to keratinocytes.

Papillary Layer

The upper layer of the dermis made of loose areolar connective tissue with many blood vessels.

Reticular Layer

The deeper layer of the dermis made of dense irregular connective tissue.

Hassinian Corpuscle

Another name for Pacinian corpuscles, which respond to pressure.

Glycolipid

A type of lipid that helps prevent water loss from the skin.

Basal Cell Layer

The lowest layer of the epidermis where cell division occurs.

Keratins

Fibrous proteins that make up hair, nails, and the outer layer of skin.

Cutaneous Membrane

The term for the skin, comprising the epidermis and dermis.

Accessory Structures

Structures associated with the skin, including hair, nails, and glands.

Microbial Defense

Protection against harmful microbes that the skin provides.

UV Radiation Damage

Potential harm to living cells in the epidermis caused by ultraviolet rays.

Arector Pili Muscle

Small muscle attached to hair follicles that causes hairs to stand up when contracted.

Cellular Autophagy

The process of cells breaking down and recycling cellular components.

Lymph Vessels

Vessels that transport lymph, crucial for the immune system.

Touch Sensitivity

The ability to detect tactile stimuli, higher in certain areas like fingertips.

Waterproof Barrier

The function of the stratum corneum that prevents water loss.

Innervation

The supply of nerves to a body part, including skin and its structures.

Subcutaneous Membrane

Another term for the hypodermis, which is involved in fat storage.

Stratum Granulosum Function

To produce keratin and water-repelling glycolipids.

Skin Function - Protection

The primary role of skin is to provide a barrier against environmental harm.

Skin Color Influencers

Factors such as melanin, keratin, and hemoglobin that determine skin color.

Skin Condition Monitoring

Regular observation of moles and skin changes to detect potential issues.

Skin Aging Effects

Changes in the skin due to aging, including wrinkles and reduced elasticity.

Sebaceous Gland Function

To secrete sebum, which lubricates and protects the skin.

Skin as Sensory Organ

Role of skin in detecting touch, pain, and temperature.

Skin Cooling Mechanism

The process of evaporation of sweat and blood vessel dilation to lower body temperature.

Skin Reaction to Cold

Constriction of blood vessels to minimize heat loss in cold temperatures.

Adipose Storage Role

Function of the hypodermis in storing fats for insulation and cushioning.