Chapter 5: Integumentary System Flashcards
Means covering
Integument
Major functions of of the integumentary system
- Protection
- Sensation
- Vitamin D production
- Temperature regulation
- Excretion
Skin provides protection against abrasion and ultraviolet light (function)
Protection
Prevents microorganisms from entering the body and reduces water loss, thus preventing dehydration (function)
Protection
The integumentary system has sensory receptors that can detect heat, cold, touch, pressure, and pain (function)
Sensation
When exposed to ultraviolet light, skin produces s molecule that can be transformed into vitamin D (function)
Vitamin D production
Important regulator of calcium homeostasis
Vitamin D
The amount of blood flow beneath the skin’s surface and the activity of sweat glands in the skin both help regulate body temperature. (Function)
Temperature regulation
Small amounts of waste products are lost through the skin and in gland secretions (function)
Excretion
Two major tissue layers of the skin
Epidermis
Dermis
Most superficial layer of skin
Epidermis
Layer of epithelial tissue that rests on the dermis
Epidermis
Layer of dense connective tissue
Dermis
Prevents water loss and resists abrasion
Epidermis
Responsible for most of the skin’ s structural strength
Dermis
Layer of connective tissue
Subcutaneous tissue
Not part of the skin, but it does not connect the skin to underlying muscle or baste
Subcutaneous tissue
Stratified squamous epithelium
Epidermis
In its deepest layers, new cells are produced by mitosis
Epidermis
As new cells form, they push older cells to the surface
Slough or flake off
Cells change shape and chemical composition
Keratinization
Protein that makes the epidermis hard
Keratin
Distinct layers
Strata
Deepest stratum
Stratum basale
Consists of cuboidal or columnar cells that undergo mitotic divisions about every 19 days
Stratum basale
Most superficial stratum of the epidermis
Stratum corneum
Consists of dead squamous cells filled with keratin
Stratum corneum
Gives the stratum corneum it’s structural strength
Keratin
Excessive sloughing of stratum corneum cells from the surface of the scalp
Dandruff
Skin subjected to friction, producing a thickened area
Callus
Stratum corneum can thicken to form a cone-shaped structure called
Corn
Composed of dense collagenous connective tissue containing fibroblasts, adipocytes and macrophages
Dermis
Responsible for the structural strength of the dermis
Collagen and elastic fibers
Part of an animal hide from which leather is made
Dermis
Oriented in many different directions and can resist stretch
Collagen fibers of the dermis
Most resistant to stretch along those lines
Cleavage lines, or tension lines
Develop when a person increases in size quite rapidly
Stretch marks
Upper part of the dermis has projections which extends toward the epidermis
Dermal papillae
Contain many blood vessels that supply the overlying epidermis with nutrients, move waste products, and help regulate body temperature
Dermis papillae
Factors that determine skin color
Pigments in the skin
Blood circulating through the skin
Thickness of the stratum corneum
Group of pigments primarily responsible for skin, hair, and eye color
Melanin
Provide protection against ultraviolet light from the sun
Melanin