7 Integumentary System Flashcards
What structures (in the body) are part of the integumentary system? (4)
- Skin
- hair
- glands
- nails
What does “integument” mean?
Covering
List the main functions of the integumentary system. (5)
- Protection
- Sensation
- Vitamin D production
- Temperature regulation
- Excretion
What are the sensory receptors in the integumentary system capable of detecting? (5)
- Heat
- cold
- touch
- pressure
- pain
How does the integumentary system provide protection? (7)
Given the structures:
- Melanin
- Skin
- Hair
- Eyebrows
- Eyelashes
- Nose/ear hair
- Skin lipids
- Melanin absorbs UV light.
- Blocks microorganisms and foreign substances.
- Hair insulates heat (head).
- Eyebrows block sweat from eyes.
- Eyelashes protect eyes from foreign objects.
- Nose/ear hair filters particles.
- Skin lipids reduce water loss.
Describe the process of Vitamin D production in the integumentary system. (5)
UV light → precursor molecule → blood to liver (modification) → kidneys (further modification) → active Vitamin D formation.
Why is vitamin D important?
helps regulate calcium and phosphorus levels
Maintaining body temperature within normal range despite environmental changes.
thermoregulation
List the four mechanisms of temperature regulation in the integumentary system. (4)
- Radiation (infrared energy)
- Convection (air movement)
- Conduction (direct contact with an object)
- Perspiration
How does the integumentary system contribute to excretion?
Small amounts of waste are lost through gland secretions in the skin.
What are the two major layers of the skin?
Epidermis and dermis
The most superficial layer of skin, made of epithelial tissue.
Epidermis
A layer of dense connective tissue below the epidermis.
Dermis
What does the skin rest on?
Subcutaneous tissue (not part of the skin), a layer of connective tissue.
What are the functions of the epidermis? (2)
- Prevents water loss
- resists abrasion.
What type of epithelium is the epidermis?
Keratinized stratified squamous epithelium.
What is the most superficial layer of the epidermis?
stratum corneum
What is found in the stratum corneum, and what is its role?
Dead squamous cells filled with keratin; keratin provides structural strength.
Cells in the deepest strata perform __, pushing older cells to the surface, where they flake off.
mitosis
How does cell movement in the epidermis occur? (5)
- New cells form by mitosis.
- Older cells are pushed to the surface.
- Cells change shape and chemical composition.
- Keratinization
- Outer layer of dead epithelial cells (resists abrasion and forms a permeability barrier)
Cells of the epidermis that are the body’s most abundant epithelial cells, containing large amounts of keratin, providing structural strength to the stratum corneum.
keratinocytes
The deepest layer of the epidermis, consisting of cuboidal or columnar cells that undergo mitotic division approximately every 19 days.
stratum basale
Cells in this layer have many desmosomes, giving them a spiny appearance.
stratum spinosum
A thin layer of cells in the epidermis.
stratum granulosum
A thin, clear layer of dead skin cells in the epidermis with a translucent appearance.
stratum lucidum
The outermost layer of the epidermis, consisting of 25+ layers of dead squamous cells filled with keratin and joined by desmosomes, surrounded by lipids.
stratum corneum
What type of tissue composes the dermis (1) and what does it contain (3)?
Dense collagenous connective tissue containing:
- fibroblasts
- adipocytes
- macrophages
What structures extend into the dermis? (5)
- Nerves
- hair follicles
- smooth muscles
- glands
- lymphatic vessels
What gives the dermis its structural strength and resistance to stretch? (2)
- Collagen fibers (oriented in many directions)
- elastic fibers
Dermis: Areas where collagen fibers are more aligned, making the skin more resistant to stretch; incisions parallel to these lines gap less and produce less scar tissue.
cleavage lines (or tension lines)
What happens if the dermis is overstretched?
lead to damage and the formation of stretch marks
Projections in the upper dermis containing blood vessels, forming ridges in the palms, soles, and digits that create fingerprints and footprints.
dermal papillae