1. What causes freckles to form?
Ellie Walker
E Block

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What are freckles?
Freckles are pigment-producing cells in our skin (melanocytes)
Mostly visible on people who have fair skin and/or red hair
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3. What are freckles in relation to skin?
Low concentration of melanin in their skin
More likely to have freckles
Due to not as much
protection from the sun
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4. What causes the pigment in freckles?
The freckles contain a pigment called melanin
Melanin is made up of melanocytes
UV rays activate the melanocytes which makes freckles darker

5. What is the difference between freckles and moles?
Freckles are temporary brown spots caused by sun
Moles are permanent dark spots (formed by skin cells (melanocytes) grow in a cluster rather than spreading out
Both very common
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6. What causes freckles to form on skin?
The more sun exposure, the more freckles
When you are out in the sun for a long time your skin produces more melanocytes to protect skin
With the more protection
the more pigment shows
Causing the formation of
freckles/dark spots
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7. Genetic Freckles MC1R gene is the cause of genetic freckles
MC1R gene is a set of instructions for making the MC1R protein
The MC1R protein is located outside of melanocytes where it balances the pigments in hair and skin
Eumelanin (every other color) & Pheomelanin (red hair and freckle color)
MC1R turns pheomelanin into eumelanin
When MC1R is broken, red hair is produced
I have brown hair and freckles, this is due to how many copies of MC1R genes I have

8. Why is this topic important to me?
The topic of freckles forming on the skin is because I also have freckles
Have grown up thinking one thing but this research help broaden my horizon
My freckles are genetic (comes from my mom and dad)

9. Cited Sources
“Freckles, Moles and Melanomas.” Cambridge University Hospitals. Web. 16
Sept
Hanson Kerry M.; Gratton Enrico; Bardeen Christopher J. (2006). “Sunscreen
enhancement of UV-induced reative oxygen species in the skin”. Free
Radical Biology and Medicine.
“Moles, Freckles, Skin Tags: Types, Causes, Treatments.” WebMD. WebMD,
Web. 20 Sept. 16
Robbins and Cotran Pathologic Basis of Disease Elsevier Page 1232.
ISBN
“What Causes Freckles?” Wonderopolis Web. 16 Sept. 2016
“What Causes Freckles.” Freckles Web. 16 Sept. 2016
“Why Do Freckles Come out in the Sun?” HowStuffWorks. 04 Aug
Web. 20 Sept. 2016
Gnanashanmugam, By Dr. Devasena. “Understanding Genetics.” Understanding Genetics.
Web. 21 Sept. 2016