Integumenrary System Flashcards
What kind of membrane is skin?
Skin
Main layers of skin from superficial to deep
Epidermis
Dermis
Hypodermis
Epidermis is the what layer
Outer
What type of epithelium is the epidermis?
Keratinized stratified squamous
The epidermis is hardened by keratin making it what?
Avascular
The epidermis has the ability to do what?
Renew itself
How often does the epidermis renew?
Every 45 days
Epidermis cell types:
Melanocytes
Keratinocytes
Keratinocytes
Keratin
What is keratin?
A waterproofing protein
Where does keratin originate?
Deeper layers, moving to surface
What junctions connect keratinocytes?
Desmosomes and tight
Where is cell production and keratinization accelerated?
Areas of friction
Thickened skin
Callus
What do melanocytes produce?
Melanin
Where does melanin accumulate?
On the superficial side of the nucleus
Why is melanin important?
To prevent DNA mutation from UV radiation
Strata if the epidermis from deep for superficial
Stratum basale Stratum spinosum Stratum granulosum Stratum lucidum Stratum corneum
Highly mitotic stratum
Basale
Stratum basale contains how much melanocytes?
App 25%
Slightly mitotic stratum
Spinosum
What type of macrophages are in the spinosum?
Langerhans
Where does synthesis of tonofilaments occur?
Stratum spinosum
Stratum granulosum contains what cells?
Langerhans
Stratum granulosum contains what granules?
Keratohyalin
Where is stratum lucidum found?
Thicker epidermis
I.e. Palms, soles, callus
Stratum lucidum is completely
Keratinized
In stratum lucidum keratin fibrils are formed by what
Keratohyalin granules and tonofilaments
The stratum corneum is completely
Keratinized and dead
Stratum corneum is what texture to provide what protection
Tough and waterproof
What layer of the epidermis do we shed constantly?
Stratum corneum
Types of membranes
Cutaneous
Mucous
Serous
The strong and flexible, second layer of skin
Dermis
Two layers of the dermis
Papillary
Reticular
Which dermal layer contains areolar connective tissue?
Papillary
An indent into the epidermis, forming fingerprints
Dermal papillae
Where is the dermal papillae found?
Papillary layer
Contains nerve receptors, capillary loops, etc…
Dermal papillae
Where are blisters present?
At dermal-epidermal junctions
Blisters occur at what junctions
Desmosomes
Separation due to mechanical stress
Blister
What dermal layer is made up of dense, irregular, connective tissue
Reticular
Blood vessels, nerve receptors, and glands are present in what dermal layer?
Reticular
Cleavage are present between what?
Collagen bundles
Cleavage lines are present at one dermal layer?
Reticular
What is present where the dermis is secured to the hypodermis?
Flexure lines
What layer of the dermis are flexure lines present?
Reticular
Dermal tears are often called
Stretch marks
Stretch marks are found on the
Reticular layer
Third layer of skin
Hypodermis
Is the hypodermis usually considered part of the skin?
No
What is the hypodermis typically classified as?
Superficial fascia
What is the job of the hypodermis?
Anchors skin to underlying organs
What is the hypodermis mostly composed of?
Adipose tissue
Is the hypodermis vascular?
Yes, very
Which layer is the site of subcutaneous injections
Hypodermis
Skin color is determined by a combo of?
Types of pigments present
Blood circulation
Stratum corneum thickness
Two pigments present in skin color
Melanin
Carotene
Yellow, brown or black skin pigments
Melanin
Pigment produced in melanocytes
Melanin
Where are melanocytes found?
Stratum basale
Melanocytes are transferred to?
Keratinocytes
Local accumulations of melanin form
Freckles and pigmented moles
Amount of melanin produced depends on what two things
Genetics
Exposure to sun
Solar elastosis is
Clumping of elastin fibers
Solar elastosis =
Leathery looking skin
Orange-yellow pigment from some veggies
Carotene
Vitamin A precursor
Carotene
Vitamin A forms
Retinal
Retinal is needed for
Sight
Where does carotene accumulate?
Adipose cells
Stratum corneum cells
Hemoglobin
Skin color determinate
Oxygenated blood cells in dermis capillaries causes
Red skin coloring
What determines the extent of red coloring?
Oxygen content
Where is hemoglobin more visible/obvious?
Fair skinned individuals
Causes increase in flow
Vasodilation
Causes decrease in flow
Vasoconstriction
Skin can be used as a
Diagnostic
Skin color is influenced by what states?
Emotional
Disease
Bluish color
Lack of O2
Cyanosis coloring
Bluish color
Cyanosis means
Lack of O2
Redness means
Heat
Inflammation
Fever
Erythema coloring
Redness