Support and Movement Flashcards
How big is the integument system?
Largest system of the body.
16% of body weight.
1.5-2m^2 surface area.
Skin is the main part.
Others include: hair, nails, and glands.
What are the two components of the integument system?
Cutaneous membrane (skin)
Accessory structures: hair, nails, and glands.
What is the structure of the cutaneous membrane?
Other epidermis: epithelium
Inner dermis: cognitive tissue
Hypodermis- not part of the skin (basement membrane)
What are all the accessory structures?
Hair
Sebaceous gland
Apocrine sweat gland
Eccrine sweat gland
Mammary gland
Ceruminous glands (ears)
Nails
What are the accessory structures’s characteristics? (3)
Derived from embryonic epidermis.
Located in the dermis.
Project through the skin surface.
What is the blood and nerve supply?
Blood supply: blood vessels in the dermis, the epidermis is avascular and receives blood from the dermis though diffusion.
Nerve supply: sensory receptors for pain, temperature, touch, and pressure.
What are the seven functions of the integument system?
- Protects underlying tissues and organs
- Maintains body temperature (insulation and evaporation)
- Excretes water, salts, and organic wastes
- Synthesizes vitamin D3
- Stores lipids
- Sensation: pain – temperature – touch – pressure
- Gives shape
What is the epidermis?
Stratified squamous epithelium.
Avascular.
Keratinocytes:
most abundant cells in the epidermis
organized in layers
contain large amounts of keratin
What is keratinization (cornificatoin)?
Forming a protective layer of dead cells filled with keratin.
Occurs on all exposed skin surfaces except eyes.
Bear foot people are at higher risk due to overuse leading to thicker skin.
What is the dermal blood supply?
Arteries:
Cutaneous plexus; arterial network along the reticular layer.
Papillary plexus: capillary network in papillary layer.
Veins: venous plexus, receives blood from capillaries.
What is contusion (bruise)?
Skin blunt trauma- damage to blood vessles- blood leaks in dermis- black and blue colour.
What are bed sores (decubitus ulcers)?
Due to disturbances of dermal circulation.
Affect skin at pressure points.
Prevented by: frequent changing positions and air mattress with massaging features.
The dermis and never supply.
Never finer in the skin control blood flow, gland secretion, and sensations.
The dermis contains a number of receptors:
1. Pacinian corpuscles: pressure and vibration
2. Meissner’s corpuscles: light touch
3. Merkel discs: pressure, positions, and deep touch
4. Ruffni corpuscles: skin stretch
5. Free never endings: pain and temperature
What is the dermis?
Provides mechanical strength, flexibility and protection.
2 layers of CT.
Highly vascular.
Contains a variety of sensory receptors.
What is the hypodermis?
Subcutaneous tissue, superficial fascia.
Underneath the integument.
Quite elastic.
Stabilizes the skin and allows independent movement.
What is the structure of the hypodermis?
Areolar and adipose tissues.
Connected to the reticular layer of the dermis by connective tissue fibres.
Fats (lipid) storage.
What is the clinical importance of the hypodermis?
Has few capillaries and no vital organs.
Site of subcutaneous injections and liposuction.
What is the structure of the hair?
Structure: hair, hair follicle, and accessory structures.