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  • It's AumSum Time.

  • Why do we have moles?

  • To enhance our beauty.

  • Alright.

  • Listen.

  • Our skin has cells called melanocytes.

  • They give our skin its color.

  • However sometimes, these cells tend to grow in clusters, thus forming moles.

  • Moles can be present at birth or can appear later in life.

  • They are usually black or brown and can be flat or raised.

  • Some moles may even disappear with age.

  • Usually, moles are not cancerous.

  • But doctors have come up with a rule called ABCDE rule.

  • Which will help you indicate whether the mole is cancerous or not.

  • A stands for asymmetric shape, B stands for border.

  • C stands for color, D stands for diameter and E stands for evolution.

  • Besides this, it is believed but there is no conclusive evidence that.

  • Excess exposure to sun-light and genetics might play a role in the formation of moles.

  • Why do we have 5 fingers?

  • So that we can lick our hand 5 times.

  • A theory suggests that we have 5 fingers because, together they make a perfect strong grip.

  • Using them, we can operate small objects with great control and precision.

  • Second theory suggests that 3 molecules called Bmp.

  • Wnt and Sox9 are responsible for the five fingers, since in our embryonic stage.

  • They mark out spaces specifically for these 5 fingers.

  • Another theory is related the Limb law.

  • Based on the length of the fingers.

  • This law helps us calculate the number of fingers we should have.

  • Now.

  • Limb's law using its mathematical model comes up with the answer 9.42 fingers per hand.

  • But we need fingers only on 1 side of the palm as other side is connected to an arm.

  • Hence, the final answer comes out to be 4.78.

  • That is, 5 fingers per hand.

  • Why do we have different time zones?

  • Because we have different watches.

  • No.

  • Our earth rotates on its own axis.

  • Due to this rotation, different parts of the earth receive different amounts of sunlight.

  • Thus causing morning, noon, evening and night.

  • Now, if we had one time zone, then 12 pm would be noon at some places.

  • But it would be night or evening at other places which would be inconvenient.

  • Hence, scientists made different time zones according to the earth's rotation.

  • With respect to the sun.

  • But how?

  • The earth makes one full 360 degrees rotation in 24 hours.

  • This means in one hour, the earth moves by 15 degrees.

  • Using this information, scientist divided the planet into 24 sections or time zones.

  • Each section or region was about 15 degrees wide and had a specific standard time.

  • This helped us know the proper time of the day in that part of the earth.

  • Why do we have different skin colors?

  • It is because of a pigment called melanin and ultraviolet radiation of the sun.

  • Confused?

  • Obviously.

  • Alright.

  • I will explain.

  • Millions of years ago, people living near equator received a lot of sunlight.

  • And ultraviolet radiation.

  • Now, ultraviolet radiation is actually absorbed by our skin to produce Vitamin D.

  • But excess radiation can damage our skin cells.

  • Hence, the skin of these people produced more melanin to block the excess ultraviolet radiation.

  • Thus, overtime, these people and their succeeding generations.

  • Adapted to have a higher level of melanin in their skin, making their skin darker.

  • However, people living away from equator received less sunlight and less ultraviolet radiation.

  • Hence, in order to absorb sufficient ultraviolet radiation.

  • And produce the essential Vitamin D.

  • These people and their following generations adapted to have a lower level of melanin.

  • Thus making their skin lighter.

It's AumSum Time.

Subtitles and keywords

B1 INT US ultraviolet radiation radiation ultraviolet skin melanin earth

Why do we have Moles? | #aumsum

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    AumSum   posted on 2019/08/06
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