Integumentary System Flashcards
What are the 3 Planes?
Frontal Plane/Coronal - Splits the front (anterior) from the back (posterior)
Median/Suggital - Splits the body in 2, separating right from left
Transverse/Horizontal - Parallel to the floor, divides upper and lower body
Functions of the Skin (6)
- Protection; microorganisms, dehydration, UV and mechanical dmg
- Sense; pain, temp, touch, deep pressure
- Movement
- Endocrine; synthesis of Vitamin D
- Immunity - alerts to pathogens, inflammation, repair
- Regulate temperature
What do Melanocytes do? How are they Triggered?
- Produces melanin which protects the skin from UV
- Malignant Melanoma - Ca of the melanocytes
- Triggered by exposure to UV radiation + hormone - oestrogen/progesterone
What do Langerhans Cells do? What part of the skin are they in?
- Found in Stratum Basale, Granulosum and Spinosum
- Resides in epidermis as dense networks of immune system sentinels
- Purpose - determine appropriate adaptive immune response (inflammation or tolerance)
- Ingest foreign antigens
- Interact with helper T Cells
- Activate macrophages
Where in the Skin can you find Merkel Cells? And what are they for?
- Tactile - receive touch sensation
- Located in Statum Basale near nerve endings
- Contact sensory neurones - merked disc
- Abundant in nail beds, fingertips, genitals
What are the 6 Types of Receptor Cells
Tactile Corpuscle - fine touch and pressure
Lamellated - deep pressure, vibration
Ruffini - pressure and distortion of deep dermis
Free Nerve Endings - sensory neurones (nonspecific) responding tactile, pain and temperature
Root Hair Plexus - distortion and movement
Tactile Discs/Merkel Cells - fine touch/pressure
Layers of Skin
- Statum Basale
- Stratum Spinosum
- Stratum Granulosum
- Stratum Lucidum
- Stratum Coneum
What are the parts/purpose of The Dermis?
- The thickest layer
- Contains vascular/neurological components
- Supports epidermis
- 2 Parts; Papillary dermis (thin) and Reticular dermis (thick)
Functions of Dermis (7)
- Supports epidermis
- Tensile strength (collagen)
- Elasticity (dermal elastin)
- Provide moisture to epidermis
- Protect underlying structures
- O2 and nutrient to epidermis
- Immunology functio
What is the Vascular Supply like in the Skin?
- 8-10% of blood flow found here
- Blood vessels come from deep structures making a network of capillaries
- Lined with endothelial cells for healing and clotting
What are the 4 Epidermal Appendages?
- Hair
- Sebaceous Glands
- Sudoriferous Glands
- Nails
Function of Different Hairs
- Primary function is protection
- Guards the scalp from injury and sun rays
- Eyebrows and eyelashes protect the eyes from foreign particles
- Nasal and ear hair protects from air particles
- Touch receptors associated with hair follicles are activated by the slightest touch
- Hair follicles are lined by epithelium
What do Sebaceous Glands do? And what is thr composition of Sebum?
- The secreting portion lies in the dermis and opens into necks of hair follicles
- Sebum is an oil mixture of fat cholesterol, proteins and inorganic salts
- Stops hair from drying out
- Lubricates/prevents XS evaporation
- Soft and pliable
- Inhibits growth of certain bacteria
What are Sudoriferous Glands? What are the two Types?
Sweat glands that start activity at puberty. 2 types based on structure/location. - Apocrine Glands
- Eccrine Glands
- Apocrine Glands
Where do you find Apocrine Glands?
Confined to axilla, groin, pigmented area’s of breasts and beards in men
Where in the skin & body do you find Eccrine Glands? And What is sweat and its purpose?
- Tubular/coiled and distributed throughout the body
- High concs found in forehead, palms, feet soles
- Secretory portion found in dermis or subcutaneous layer, surrounded by blood vessels
- Its excretory duct is sweat pores
- Sweat is composed of water, lactic acid, amino acids, NH3, sebum, salts, NaCl, urea and sugar
- Sweat’s purpose is to regulate body temperature
Purpose and Contents and Subcutaneous Layer?
- In hypodermis
- Not official part of the skin
- Has adipose tissue, fat stores therefore stores energy
- Provides insulation and shock absorption
What Can be Absorbed through the Skin
- Fat soluble vitamin; A, D, E and K
- Certain drugs
- Toxic materials - acetone, salts, heavy metals eg Pb, Mc, poison ivy
- O2 and CO2
Vitamin D Synthesis
- Synthesised in the epidermal layer when exposed to UV radiation
- In sunlight cholecalciferol is derived from the steroid cholesterol
- The liver converts cholecalciferol -> calcidiol → calcitriol in the kidneys
- Purpose is for the absorption of Ca, P for healthy bones
Vitamin Deficiencies
- Absence of Vitamin D can lead to rickets where bones are misshapen due to lack of Ca causing bow leggedness
- Deficiency in the elderly can mean osteomalacia (softening of the bones)
- Vitamin D also helps with general immunity against bacteria, virus, fungal infection. Deficiency also linked to cancer
5 Type of Burn Injuries
Thermal Burns - external heat sources causing tissue death or charring. Hot metals, scalding liquid, steam, flames
Radiation Burns - Caused by prolonged exposure to UV rays or therapeutic cancer treatment or nuclear plant leaks
Chemical Burns - caused by strong acids, alkaline, detergents, solvents coming in contact with skin or eyes
Electrical Burns - burns from electrical current, AC or DC
Friction Burns - Direct dmg to cells the heat generated by friction eg rope/treadmill
First 2 Burn Depths
- Superficial - Epidermis onlyAppearance; dry flaky. Heals in 3-5 days with minimal scarring
- Superficial partial thickness - upper 1/3 dermis
Appearance; painful blisters, maybe oedema, eschar (thick leathery surface of dead tissue). Minimal scarring, heals within 1-2 weeks
2nd Two Burn Depths
- Deep partial thickness - All of dermis
Appearance; red waxy, reduced pain sensation, blisters and eschar. Heals in 2-3 weeks, surgical intervention needed to prevent significant scarring.
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Full thickness - epidermis/subcutaneous
Appearance: bloodless-pear-white, eschar, hair easily plucked. Requires surgical interventio
Rule of Nine
Tool for estimating % area of burn where the body is divided into sections of 9%
