Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
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A lock (
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connected to the .gov website. Share sensitive
information only on official, secure websites.
Schematic showing the pathways photons can take when travelling through the skin. Absorption is depicted as red stars; brown spots in the epidermis represent melanin; in the dermis blood vessels are represented by blue and red lines, collagen fibers by gray lines, and elastin by green dots.
