Kin 131 exam integumentary system Flashcards
What does the integumentary system include?
- Skin
- assessor structures
- Hair, nails, glands
What are the 7 primary functions of the integumentary system?
- protection
- UV protection (melanin)
- Physical trauma protection
- Protection against fluid loss - Excretion
- Gets rid of waste via sweat - Lubrication
- sebaceous glands produce oil - Body temperature
- Vasoconstriction = reduce temperature in target area
- Vasodilation = increase temperature in target areas - Vitamin D synthesis
- Produces vitamin D which produces a hormone called calcytrial that facilitates absorption of calcium - Lipid storage
- Helps insulate body and provide energy - Sensations
- contains receptors that help us understand the world around us
Explain the anatomy of the cutaneous layer and the subcutaneous layer
- Cutaneous layer:
- Epidermis
- Dermis - Subcutaneous layer
- Hypodermis (provides support functions)
Explain the cutaneous and subcutaneous layers of the skin in depth
- Epidermis:
- The outermost layer of the skin.
- Made up of 4-5 layers of tightly packed stratified squamous epithelial cells (flat cells stacked on top of each other).
- The epidermis acts as a barrier to protect the body from the environment. - Dermis:
- The inner layer of the skin, beneath the epidermis.
- Made up of 2 layers
- The dermis contains blood vessels, lymphatic vessels, glands, nerves, and hair follicles. It supports and nourishes the epidermis. - Hypodermis (Subcutaneous Layer):
- Located beneath the dermis.
- Highly vascularized (rich in blood vessels).
- The hypodermis connects the skin to the underlying fascia
What is the epidermis primary made of? What does it do?
keratinocytes, which primary provide hardness and water resistance
How many layers are in the epidermis?
Either 4 or 5
- 5 layers in thick skin: Palms and soles of feet
- 4 layers in thin skin: rest of body
Explain the different layers of the epidermis
- Stratum basale (stratum germanium):
- Deepest layer
- Single layer of basal cells (turn into keratinocytes)
- Attaches epidermis to the dermis * - Stratum spinosum:
- 2nd deepest layer
- 8-10 layers of keratinocytes
- Keratonocytes begin to synthesize keratin
- Contains langerhans that act as macrophages, cleaning up unwanted substances - Stratum granulosum:
- 3rd deepest layer
- grainy appearance
- 3-5 layers of keratonocytes
- produces the largest amount of keratin
- produces keratohylin (protein that helps with waterproofing)
- Cells become flatter and begin to die - Stratum lucidum:
- Only in thick skin
- Cells are flattened and dead
- contains eledein (increases waterproofing and physical strength) - Stratum corner
- Outtermost layer
- 15-30 layers of keratonocytes
- layers of dead cells
- entire layers if replaced every 4 weeks ish
What are basal cells
cuboidal shape stem cells that turn into keratinocytes
What is keratin?
A protein known for being tough and water resistant (called a scleroprotein)
Explain what can effect the colour of skin
- Melanin:
- Produced by melanocytes
- packaged into melanasomes
- further the melanosomes travel into the epidermis layers before being broken down and the larger they are = darker skin
- Melanin protects skin from UV damage
Melanin production is stimulated by UV exposure - Carotene
- Causes a yellow/orange pigment - Circulation and temperature
- Oxyhemoglobin (oxygenated blood) = red colour
- Cyanosis: caused by deoxygenated blood = blue colour
- Cold = vasoconstriction = blue
- Hot =. vasodilation = red
What does having too much melanin do?
Can affect synthesis of vitamin D as it blocks too much UV light
Explain the dermis and its layers
- Found beneath the epidermis layers
- Made of collagen and elastin fibres which give the skin strength and flexibility
- Has 2 layers:
- Papillary layer:
- Superficial layer
- Has dermal papilla which are bumps that form fingerprints and are used to lock the dermis to the epidermis - Reticular layer
- Deeper layer
- Dense irregular tissue
- Contains hair follicles, sweat and oil glands
- stronger and less flexible than papillary layer
Explain what lines of cleavage are
- The orientation of the underlying collagen fibers in the body
- Provides better resistance to certain forces
- In surgery, cuts are made with the lines of cleavage as it reduces scaring
Explain the integumentary system accessory structure: Hair
- Made of dead keratinocytes
- Hair grows from a structure called the hair follicle, which is a tiny pocket in the skin.
- The hair follicle is an extension of the epidermis (the outer skin layer) that dips into the dermis (the deeper skin layer).
- Inside the hair follicle, there are several important parts (Hair root: beneath the skin):
1. Hair bulb: Structure at the base of the hair
2. Hair matrix: The part of the bulb where cells rapidly divide and produce new hair.
3. Hair papilla: A structure at the base of the bulb that contains blood vessels, which nourish the growing hair. - (Hair shaft: above the skin): Part of the hair that’s above the skin
What are the layers of the hair?
- Medulla: Core part of the hair
- Cortex: Layer pf compressed keratinized cells that’s around the medulla
- Cuticle Hard keratinized cells that form outside of hair
What are the main functions of hair?
- Protection
- protection from sun - Sensory info
- Root hair plexus - Thermoregulation
protection from heat and cold
4.comunication
- With sympathetic activation the hairs stand up
Explain the stages of hair growth
- Anlagen stage:
- Lasts 2-7 years
- Cells dividing rapidly and pushing the hair out of the follicle - Catogen stage
- Lasts 2-3 weeks
- Transition from growth to rest
- Slowed growth - Telogen stage
- Lasts 2-4 months
- No new growth
- Old hair shed and cycle repeats
What’s is hair growth affected by:
Age, Hormones, Stress, Meds
Explain the main function and types of sweat glands
- Eliminate waste and regulate temp through sweat
2 main types:
- Eccrine:
- Coiled structure
- Secrete sweat directly onto the skin
- Secretion is watery and clear
- main function is thermoregulation - Apocrine
- Secrete sweat into hair follicles
- Secretion is thicker and cloudier acting as nutrient for bacteria living on the skin
- secretion due to stress or puberty
explain oil glands and their function
- Sebaceous glands secrete a oily substance called sebum into hair follicles
Functions:
- Provides lubrication to the epidermis to keep it soft and flexible
- Helps clean the skin
- helps with waterproofing
Explain nails and their structure
- hard structure at the ends of digits made of dead keratinocytes
Structure:
- Nail body: hidden base part of the nail under the cuticle
- Nail matrix: Area where the basal cells produce new cells that turn to keratinocytes
- Nail body: Nail itself
- Lunula: White half moon structure at the base of the nail
- Cuticle: dead layers of cells that sit overtop the nail root
- Proximal and lateral nail folds: sides of the nails
- Nail bed: Skin underneath the nail body
- hyponychium: dead skin underneath the nail free edge
How fast is the nail growing? What’s it a good indicator of
Matrix produces new cells at a rate growing the nail 3mm a month. good indicator of mineral deficiency if bumps on nail
How age affects the integumentary system
- fewer melanocytes
- become paler - Decrease in germinative cell division
- Thinner epidermis
- lose ability so synthesize vitamin D - Fewer elastin fibers
- Saggy skin - Eccrine sweat glands are less active
- less effective at regulating temp - Less active hair follicles
- less hair - reduced sebaceous gland activity
- dryer skin - reduced sex hormones
what is albinisme and vitiligo?
A disorder resulting in the absence of melanocytes
- in albinisme it affects the eyes skin and hair
- In vitiligo its only affects some areas of the skin
neither have a direct impact on lifespan but indirect factors caused by them do affect lifespan
What is skin cancer?
-Abnormal uncontrollable growth of cells
-When theirs a flip a switch often caused by radiation that causes a cell to divide rapidly without dying, causing a large buildup of cells. This steals nutrient away from the rest of the body
What is carcinoma and what are the different types?
- cancer in the epithelial cells of the skin
- Basal cell carcinoma
- Most common
- Doesn’t tend to spread
- Buildup of cells in the stratum germinative - Squamous cell carcinoma
- Buildup of cells in the stratum spinuosum
- Non life threatening unless untreated - Melanoma
- Lest common and most dangerous
How are moles assessed?
Asymmetrical
Boarders
- fuzzy borders = bad
Colour
- white or abnormal colour = bad
Diameter
- over 6mm = bad
Evolving
-changing over time
how are moles treated?
- Remove mole and tissue around it
- If all cancer is removed then stop
- If cancer is still present new treatment such as chemotherapy begins
What are the different types of burns
- First degree
- Burn to the epidermis - Second degree
- burn to the dermis - Third degree
- Burn to the hypodermic
not painful - Fourth degree
- burn to the facia or bone
What are the types of wound healing
- Primary intention
- wound edges are brought together - Secondary intention
- wound edges are too far apart so wound heals from bottom up - Tertiary intention
- Mix of the first two, wound is left to close then brought together
W\Explain the wound healing stages
- Hemostasis
- Clot formation
- vasoconstriction - Inflammatory
- Vasodilation occurs bringing immune cells - Proliferative
- New cells are built to repair damage - Remodelling / maturing
- Collagen strengthens and reorganizes itself
what is a scar and What are the types of scars?
Scar: High density of collagen fibers
Atrophic scar:
- Has a indented structure
- Less collagen fibers than other scars
Hypertrophic scar
- Bubbles out structure but stays within injury area
- Has more collagen then normal scars
Keloid scar:
- Extreme amounts of collagen
- Scar bubbles out and expand outside of the injury area
