PATHOLOGY MCQ
SKIN
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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People with less melanin living near the equator
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People with less melanin living near the poles
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People with more melanin living near the equator
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People with more melanin living near the poles
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Detailed explanation-1: -Light-skinned people who live near the equator with high sunlight are at an increased risk of folate depletion. As a consequence of folate depletion, they are at a higher risk of DNA damage, birth defects, and numerous types of cancers, especially skin cancer.
Detailed explanation-2: -There is a direct correlation between the geographic distribution of ultraviolet radiation (UVR) and the distribution of indigenous skin pigmentation around the world. Areas that receive higher amounts of UVR, generally located closer to the equator, tend to have darker-skinned populations.
Detailed explanation-3: -If your ancestors lived in an area that received large amounts of UV radiation (i.e. closer to the equator) humans evolved darker skin for protection through the process of natural selection. However light is also important since it allows humans to synthesize vitamin D.
Detailed explanation-4: -Some experts believe that people who have darker skin are more prone to vitamin D deficiency than people with lighter skin. This is because excess melanin absorbs the UV rays responsible for vitamin D synthesis.