Why do we have to wear sunscreen? - Kevin P. Boyd
View full lesson: http://ed.ted.com/lessons/why-do-we-have-to-wear-sunscreen-kevin-p-boyd You already know that a trip to the beach can give you a nasty sunburn, but the nitty gritty of sun...
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Most of us think of the Sun as our friend. It helps plants grow, keeps us warm, and who doesn't love to lie on the beach on a sunny day? But for all of it's good qualities, the Sun can also be harmful in large amounts. That's why we invented sunscreen. The purpose of sunscreen is to shield the body from the Sun's ultraviolet rays, which have several harmful effects, including sunburn, aging, and skin cancer promotion. These rays are separated by their different wave lengths, into types such as UVA and UVB, which exert a variety of effects in the skin due to the absorption patterns of chromophores, the parts of the molecules responsible for their color. The primary two chromophores are hemoglobin, found in our red blood cells, an...
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Most of us think of the Sun as our friend. It helps plants grow, keeps us warm, and who doesn't love to lie on the beach on a sunny day? But for all of it's good qualities, the Sun can also be harmful in large amounts. That's why we invented sunscreen. The purpose of sunscreen is to shield the body from the Sun's ultraviolet rays, which have several harmful effects, including sunburn, aging, and skin cancer promotion. These rays are separated by their different wave lengths, into types such as UVA and UVB, which exert a variety of effects in the skin due to the absorption patterns of chromophores, the parts of the molecules responsible for their color. The primary two chromophores are hemoglobin, found in our red blood cells, an...
