Integumentary System Flashcards
Name the 3 main structures of the skin.
Epidermis
Dermis
Hypodermis
Explain the epidermis
• Keratinised stratified squamous epithelium cells
• Avascular
• Cells push up from basement membrane, losing blood supply and become hard, flat and dead.
Explain the stratum basale layer
• First layer of the skin
• Closest to the dermis
• Vascular
• Contain Keratinocytes & melanocytes
Explain Keratinocytes
• Product keratin
• Found in the stratum basale layer
• Keratin protects skin and tissues from heat, microbes & chemicals
• Provides a waterproof sealant
Explain Melanocytes
• Product melanin
• Found in the stratum basale layer
• Melanin contributes to skin colour
• Absorbs damaging UV rays
Risk factors for skin cancer is?
Over exposure to UV radiation.
UVA - aging
UVB - burning
6 functions of the skin
• Protection
• Excreation
• Temperature Regulation
• Sensory
• Stores Blood
• Vitamin D Synthesis
Explain the function of protection for the skin
• Langerhan Cells ingest unwanted invaders
• Protects against microbes, chemicals, abrasions, water loss/ entry, UV exposure
Explain the function of excretion for the skin
• Excretes excess salt, CO2, ammonia & urea
Explain the function of temperature regulation for the skin
• Receptors detect temperature change and skin responds.
• Goose-bumps tighten skin to make surface smaller.
• Erector-Pili muscle makes hair stand up to trap warm air against skin.
• Sweat secretes onto skin and diffuse heat when absorbed.
Explain the function of sensory for the skin
• Merkel Cells are receptors to touch, heat, cold, pain, pressure, vibration & tickle
Explain the function of storing blood for the skin
• Blood vessels vasoconstrict during shock
• Blood is then redirected to vital organs.
Explain the function of vitamin D synthesis for the skin
• Cholesterol converts to Vit D in the skin during UV exposure
• Converted to calcitriol & distributed into the bones.
• 2x 10min exposure per week
What are the 7 age related changes for the skin?
• Wrinkling
• Melanocyte Decreases
• Hair Loss
• Reduced Sweat Production
• Sebaceous Glands Atrophy
• Poor Skin Healing
• Blood Vessel Walls Thicken
Explain wrinkling
• Collagen fibres decrease & stiffen
• Elastin fibres lose elasticity (UV exposure & smoking)
Explain melanocytes Decreasing
• The cause of grey hair
Explain hair loss
• Follicles stop producing hair
• Normally starts anterior to the hair line working its way posterior
Explain reduced sweat production
• Older people can over heat due to lack of sweat screations.
Explain sebaceous gland atrophy
• Lack of oil on the skin can cause dry, cracking skin
Explain poor skin healing
• Susceptible to skin tears, prolonged healing and skin cancer
Explain thickened blood vessel wall
• Decrease nutrient availability & absorption
• Thinner skin = subcutaneous fat is lost.
