Sun-Induced Skin Disorders Flashcards
UV spectrum represents ____% of total solar energy
<10
UV-B wavelengths are found in ___ to ___nm
290-320
UV-A wavelengths are found in ___ to ___nm
320-400
Which UV wavelength produces redness + erythema?
UV-B
Which UV wavelength penetrates deeper into skin?
UV-A
Wavelengths of ____ to ____ are visible to human eye
400 + 700
What is the outermost epidermal layer?
Stratum corneum
What is a chromophore?
Exogenous or endogenous photo-abosrbing chemicals in the skin
What causes skin to absorb, excite and transfer energy to make ROS that structurally damages skin?
Chromophore
What layer of the skin is a major absorber of UV-B?
Stratum corneum
The underlying dermis is rich in _____ and ______
collagens + elastin
UV-A readily penetrates the ______
dermis
Melanoma vs Nonmelanoma
Risk increases w/ age
Both
Melanoma vs Nonmelanoma
Develops in upper and middle epidermis
Nonmelanoma
Melanoma vs Nonmelanoma
Begins in lowest layer of epidermis
Malanoma
Melanoma vs Nonmelanoma
Risk factors include: males, moles, tanning beds, etc
Nonmelanoma
What is the ABCDE rule of moles?
Asymmetry Border Color Diameter (>6mm) Evolving
When is the highest intensity of sunburn (erythema)
10am to 4pm
UV-A vs UV-B
Primary inducer of skin cancer
UV-B
UV-A vs UV-B
Causes immunosuppression
UV-A
UV-A vs UV-B
DNA + tissue damage which lead to photoaging
UV-A
UV-A vs UV-B
Has therapeutic effects such as Vit. D synthesis
UV-B
(T/F) Cloud covers filter most UVR
False; very little coverage
When using tanning beds, UV-B exposure should be restricted to not more than ___% and most have ____% UV-A (greater than natural sunlight)
5 + 96
(Higher/Lower) altitude increases UVR exposure
Higher
Being (close to/far away from) the equator increases UVR exposure
close to
Higher altitude (increases/decreases) UVR exposure
increases
Proximity to equator (increases/decreases) UVR exposure
increases
Window glass blocks (UV-A/UV-B) penetration but not (UV-A/UV-B)
UV-B + UV-A
Most car windshields use laminated glass which filter out most of UV-__ except side windows
A
Fresh snow reflects ____% of radiation
80-85
Soil, grass, and water reflect ____% of radiation
<5
Which is more protective, dry or wet fabric?
Dry fabric
The skin tans by producing _____
melanin
Sunburns are a result of vaso(dilation/constriction) of dermal blood vessels
dilation
Sunsburns develop about __-___ hours after exposure but peaks about __-__ hours
4 to 12 + 12 to 24
Melanin provides photoprotection, but not ____ protection
cancer
What age group should not use sunscreen?
<6 months in age
SPF 2-14 provides UV-__ and sunburn protection
B
SPF __ is the minimum for skin cancer prevention
15
SPF ___ is for someone w/ light skin that easily burns + rarely tans
30
SPF ___ is the maximum you should use
50
What is used to calculate SPF?
Minimal erythema dose (MED)
What do chemical sunscreens do to UVR?
Absorbs + blocks transmission of UVR to epidermis
Who do physical sunscreens do to UVR?
Opaque and reflects/scatter UVR
