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It's AumSum Time.
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Why do we have moles?
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To enhance our beauty.
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Alright.
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Listen.
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Our skin has cells called melanocytes.
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They give our skin its color.
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However sometimes, these cells tend to grow in clusters, thus forming moles.
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Moles can be present at birth or can appear later in life.
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They are usually black or brown and can be flat or raised.
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Some moles may even disappear with age.
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Usually, moles are not cancerous.
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But doctors have come up with a rule called ABCDE rule.
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Which will help you indicate whether the mole is cancerous or not.
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A stands for asymmetric shape, B stands for border.
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C stands for color, D stands for diameter and E stands for evolution.
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Besides this, it is believed but there is no conclusive evidence that.
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Excess exposure to sun-light and genetics might play a role in the formation of moles.
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Why do we have 5 fingers?
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So that we can lick our hand 5 times.
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A theory suggests that we have 5 fingers because, together they make a perfect strong grip.
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Using them, we can operate small objects with great control and precision.
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Second theory suggests that 3 molecules called Bmp.
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Wnt and Sox9 are responsible for the five fingers, since in our embryonic stage.
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They mark out spaces specifically for these 5 fingers.
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Another theory is related the Limb law.
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Based on the length of the fingers.
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This law helps us calculate the number of fingers we should have.
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Now.
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Limb's law using its mathematical model comes up with the answer 9.42 fingers per hand.
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But we need fingers only on 1 side of the palm as other side is connected to an arm.
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Hence, the final answer comes out to be 4.78.
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That is, 5 fingers per hand.
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Why do we have different time zones?
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Because we have different watches.
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No.
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Our earth rotates on its own axis.
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Due to this rotation, different parts of the earth receive different amounts of sunlight.
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Thus causing morning, noon, evening and night.
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Now, if we had one time zone, then 12 pm would be noon at some places.
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But it would be night or evening at other places which would be inconvenient.
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Hence, scientists made different time zones according to the earth's rotation.
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With respect to the sun.
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But how?
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The earth makes one full 360 degrees rotation in 24 hours.
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This means in one hour, the earth moves by 15 degrees.
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Using this information, scientist divided the planet into 24 sections or time zones.
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Each section or region was about 15 degrees wide and had a specific standard time.
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This helped us know the proper time of the day in that part of the earth.
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Why do we have different skin colors?
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It is because of a pigment called melanin and ultraviolet radiation of the sun.
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Confused?
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Obviously.
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Alright.
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I will explain.
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Millions of years ago, people living near equator received a lot of sunlight.
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And ultraviolet radiation.
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Now, ultraviolet radiation is actually absorbed by our skin to produce Vitamin D.
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But excess radiation can damage our skin cells.
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Hence, the skin of these people produced more melanin to block the excess ultraviolet radiation.
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Thus, overtime, these people and their succeeding generations.
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Adapted to have a higher level of melanin in their skin, making their skin darker.
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However, people living away from equator received less sunlight and less ultraviolet radiation.
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Hence, in order to absorb sufficient ultraviolet radiation.
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And produce the essential Vitamin D.
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These people and their following generations adapted to have a lower level of melanin.
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Thus making their skin lighter.