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  • It's AumSum Time

  • Hi guys.

  • Can you guess the title of my next video?

  • Hurry up.

  • Write your guess in the comments section below.

  • Are wisdom teeth still useful?

  • Obviously.

  • Because wisdom teeth make us intelligent.

  • No.

  • There are 32 permanent teeth, out of which four wisdom teeth begin to grow a little late.

  • Now, when our ancient ancestors used to eat plant material and raw meat.

  • They required big strong jaws and wisdom teeth to chew their food.

  • As they learned to cook food, they no longer required those big jaws.

  • Hence, through evolution, the jaws started to get smaller and smaller.

  • But the wisdom teeth did not disappear through evolution.

  • They still exist.

  • But since they appear a little late, the remaining teeth usually take up the available space in the small jaw.

  • Leaving no room for the wisdom teeth.

  • Hence.

  • They begin to grow at odd angles and push other teeth causing pain, swelling, tooth decay and even infection.

  • Hence, in such cases, wisdom teeth can prove to be harmful and not useful.

  • Why are airplane windows oval?

  • Because I told the airplane manufacturers to do so.

  • Stop bluffing.

  • When airplanes fly at higher altitudes.

  • The air pressure inside the airplane is more than the air pressure outside.

  • Hence, the cabin slightly expands, thus creating stress which flows through the cabin's material.

  • Now, when the windows were square or rectangular.

  • The stress caused tension to build up at the corners of square windows.

  • This tension produced cracks in the cabin, thus leading to crashes.

  • So sad.

  • Hence, this design flaw was corrected by making windows oval.

  • Oval windows provide a smoother path for stress to flow due to which tension is not produced.

  • Hence, airplanes are safe.

  • How do migratory birds find their way?

  • With the help of GPS.

  • No.

  • Every year, many migratory birds fly thousands of kilometers to find food, to avoid extreme weather, etc.

  • But researchers don't know how these birds find their way and travel to the same location year after year.

  • However.

  • An observation suggests that migratory birds can detect the earth's magnetic field lines.

  • That appear to emerge from south pole and merge into north pole.

  • When migratory birds have to travel from north to south or vice versa.

  • They align themselves with the magnetic field lines and travel to their location.

  • Along with this.

  • Migratory birds may also find their way by creating a mental map of their route using mountains, rivers, etc.

  • Besides this.

  • It is also believed that migratory birds use the location of the sun and stars.

  • To find their way and reach the same location.

  • Topic: Taste Buds

  • Why mint tastes cold?

  • Maybe because it is manufactured in Antarctica.

  • Not at all.

  • Wait, I'll explain.

  • Our tongue is actually a muscle which consists of many taste buds or receptors.

  • Are they similar to my earbuds?

  • No.

  • When foods having flavors such as sweet, salty, sour, bitter or umami.

  • Come in contact with these taste receptors and activate them.

  • They send signals to the brain, telling us their taste.

  • However, when we eat mint, it feels or tastes cold.

  • This is because mint contains a compound called menthol.

  • Menthol does not activate the taste receptors.

  • But instead it activates the cold sensing receptors in our tongue.

  • Hence, these receptors send messages to our brain signaling cold.

  • As a result, the brain thinks that something cold is present in our mouth.

  • Thus making mint taste cold.

  • Why does salt make food taste better?

  • Wait.

  • I'll explain.

  • Salt which is basically sodium chloride makes almost everything taste better.

  • Whether it is French fries, certain fruits, curries or even cookies.

  • We like at least a little salt in all these foods.

  • According to researchers.

  • We have evolved to like salt maybe because our bodies need salt for survival.

  • What?

  • Salt for survival.

  • Indeed.

  • Sodium present in salt, maintains our blood pressure, transmits nerve impulses, etc.

  • Whereas, chloride is used to produce hydrochloric acid in our stomach.

  • Hence, to obtain salt, we have gradually developed a taste for it.

  • Thus, salt in food makes it appealing and tasty.

  • In addition to this, it is found that salt suppresses bitterness better than sugar.

  • Researchers aren't sure how.

  • Some researchers suggest that salt neutralizes the bitter tongue receptors.

  • While some suggest that on adding salt, the brain interprets the taste as less bitter.

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智齒還有用嗎?| 智慧牙還能用嗎? (Are Wisdom Teeth still Useful? | #aumsum)

  • 66 3
    Amy.Lin 發佈於 2021 年 01 月 14 日
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