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  • It's AumSum Time

  • Hi guys.

  • Can you guess the title of my next video?

  • Blood rain.

  • Relax.

  • Hurry up.

  • Write your guess in the comments section below.

  • Why do we feel butterflies in our stomach?

  • Because I have invited them to my party.

  • No.

  • Butterflies in our stomach are basically caused by our autonomic nervous system or ANS.

  • ANS regulates our involuntary functions like heartbeat, blood flow, digestion, etc.

  • Also, during stressful situations such as when a ferocious animal comes in front of us.

  • A part of ANS called the sympathetic nervous system prepares our body for fight or flight.

  • This means, it redirects blood from other parts of the body to mostly our hands and legs.

  • So that they get sufficient oxygen and nutrients and thus, help us fight or flight.

  • So then, why do we feel butterflies in our stomach?

  • It is believed that since blood is redirected from the stomach.

  • Millions of sensory nerves in it detect a sudden decrease in oxygen.

  • Hence, in response to this, the nerve cells create the feeling of butterflies.

  • Also, because of blood redirection, it is thought that the stomach contracts.

  • Thus contributing to the feeling of butterflies.

  • What is a mirage?

  • An invisible cloak.

  • No.

  • Mirage is an illusion in which it appears as if there is water present on the ground.

  • On a hot day, the land heats the layers of air closer to it.

  • However, as we move higher, the layers of air get relatively cooler.

  • Thus, the hot lower layers of air near the ground form rarer media and cold upper layers form denser media.

  • Now, when light coming from sky travels from denser to rarer media.

  • It bends more and more until it exceeds the critical angle.

  • That is, the angle beyond which light gets reflected.

  • This phenomenon is called total internal reflection.

  • When this reflected light reaches our eyes, our eyes trace it backward as a straight line.

  • Hence, the reflection of blue sky appears on the ground and our brain thinks that there is water.

  • Thus causing a mirage.

  • Topic: Rain.

  • Why does rain smell?

  • Maybe it applies a special perfume.

  • No.

  • Rain is just water and water doesn't have any smell.

  • Yes dude.

  • So, what's that smell?

  • The distinctive smell which frequently accompanies the first rain.

  • After a dry weather is scientifically called petrichor.

  • It basically comes from plants and bacteria called actinomycetes which live in the soil.

  • Now during a long dry spell, the plants release oils into the soil to block other seeds from germinating.

  • Thus reducing competition for water.

  • Whereas, the actinomycetes produce a chemical called geosmin.

  • Now when rain hits the ground, it brings up the oils and geosmin which then mix with air.

  • The combination of this geosmin along with the plant oils form the smell which we receive after the rain.

  • Topic: Red eye effect.

  • Why do my eyes glow red in photos?

  • Because there is a devil hidden in you.

  • Stop bluffing.

  • Alright.

  • I'll explain.

  • It happens because of blood vessels in our eyes and pupil.

  • Pupil is a small opening whose size is adjusted by the circular muscle called iris.

  • In bright light, the iris contracts making the pupil smaller.

  • Thus allowing less light to enter into our eyes.

  • In dark, the iris relaxes making the pupil larger, thus allowing more light to enter.

  • Also exposing the blood vessels in our eyes.

  • Hence, when we take a photo in such a dark environment.

  • The flash of light from the camera floods into our eyes at once.

  • Some of this light gets reflected from the blood vessels onto the camera before our iris can contract.

  • Making our eyes glow red in photos.

  • Why smoking makes people look old?

  • So that we look more experienced and intelligent.

  • No.

  • Smoking makes people look old because things like cigarettes contain nicotine.

  • Nicotine is a vasoconstrictor which means it narrows our blood vessels.

  • Restricting the blood supply.

  • When the blood supply is restricted, our cells don't get the required oxygen and nutrients.

  • As a result, our skin becomes dry and discoloured.

  • In addition to this, the collagen and elastin fibers which keep our skin firm and elastic.

  • Begin to break down much faster, leading to saggy and wrinkled skin.

  • Also, when we smoke, we purse our lips and squint our eyes.

  • Regularly repeating these actions may also cause wrinkles on our lips and around our eyes.

  • In this way, smoking makes our skin dry, saggy and wrinkled, thus making us look old.

It's AumSum Time

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B1 US blood stomach pupil iris mirage smell

Why do we feel Butterflies in our Stomach? | #aumsum

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    AumSum posted on 2019/04/08
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