INTEGUMENTERY SYSTEM
INTEGUMENTERY SYSTEM MISCELLENOUS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Exposure to UV light
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Having ancestors from near the equator
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Both answers are correct
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Neither answer is correct
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Detailed explanation-1: -UV-A rays from the sunlight penetrate into the lower layers of the epidermis and trigger the melanocytes to produce more melanin. Melanin is produced as a defence mechanism. Sunlight is the major cause of increased melanin production. Other factors include hormonal imbalances, aging and inflammation processes.
Detailed explanation-2: -It takes place in melanocytes, in separate cytoplasmic organelles called melanosomes [11]. Two major types of melanin are produced – pheomelanin and eumelanin. They differ in color and the way of synthesis.
Detailed explanation-3: -There are two types of melanin. Eumelanin is black or brown pigment and pheomelanin is red or yellow pigment. People who make lots of pheomelanin tend to have lighter skin, often because of freckling. Freckles happen when melanocytes clump together.