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  • It's AumSum Time

  • What exactly killed the dinosaurs?

  • My silly jokes.

  • No.

  • Most people believe that an asteroid killed all dinosaurs.

  • But that wasn't the only reason.

  • Dinosaurs were already declining due to volcanism, far before the asteroid impact.

  • Really?

  • Yes.

  • Super volcanic eruptions spewed out lava, dust, soot and various gases into the atmosphere.

  • This triggered a drastic climate change, slowly reducing the dinosaur count.

  • Then around 66 million years ago.

  • A 6-mile-wide asteroid crashed into the earth in Yucatán Peninsula.

  • Hold on.

  • How do you know?

  • Scientists found a layer in rocks, called K-PG boundary.

  • It is rich in Iridium.

  • Iridium isn't found on earth's surface, but is abundant in asteroids.

  • Proving that an asteroid crashed the earth.

  • This caused large rocks to blast into the air and fall back as molten rocks.

  • Huge tsunamis worsened the condition.

  • Eventually making dinosaurs extinct.

  • Topic : Heat transfer.

  • Why do we use a black umbrella in summer?

  • Hey.

  • Looks like you are heading out today.

  • But it is so hot outside.

  • Why don't you take a dark colored umbrella, preferably black?

  • See, I warned you.

  • At least now use the black umbrella.

  • Now, do you notice the heat?

  • No, right?

  • Do you know why?

  • This is because in summer season, the temperatures are quite high.

  • Now, as compared to other colors, a black colored umbrella, being dark, absorbs most of the light.

  • Ultraviolet radiations coming from the sun and gets heated.

  • It then radiates the heat back into the air.

  • Thus, making a black umbrella, a good choice to use in summers.

  • Topic: Tooth decay.

  • What causes cavities?

  • A black sketch pen.

  • No.

  • Our mouth contains billions of bacteria which live on our teeth, tongue, etc.

  • Most of these bacteria are usually harmless.

  • Just like me, right?

  • Yes.

  • Now listen.

  • A tooth consists of enamel, dentin and pulp.

  • Enamel is mostly made up of minerals.

  • Dentin is a layer underlying the enamel.

  • Whereas, pulp has blood vessels and nerves.

  • Now, when we eat foods containing sugars, some of these bacteria feed on the sugars producing acid.

  • This acid starts to dissolve the minerals of the tooth enamel, causing tooth decay.

  • Usually, our saliva restores these minerals, thus preventing further decay.

  • But if we continuously eat sugary foods, then our saliva cannot keep up.

  • Causing the bacteria to pass into the dentin and then eventually into the pulp, thus creating cavities.

  • What is an allergy?

  • It is a magic spell.

  • No.

  • Allergy is an overreaction of our immune system to usually harmless substances like peanuts, milk, pollen, etc.

  • These substances are called allergens.

  • Our immune system has white blood cells or lymphocytes.

  • Which protect us from foreign invaders such as bacteria, viruses, parasites, etc.

  • These invaders are called antigens.

  • When a lymphocyte detects an antigen, it produces antibodies.

  • Antibodies destroy antigens and thus, protect us.

  • Now, if an allergen such as pollen is inhaled by an allergic person.

  • The lymphocytes of the allergic person for unknown reasons think that the allergen is an antigen.

  • Hence, lymphocytes overreact and produce antibodies which start attacking the allergen.

  • Besides this, as a protective response, some immune cells also trigger production of excess mucus.

  • Resulting in running nose.

  • They even give rise to itching throat and watery eyes, thus causing an allergy.

  • What is diabetes?

  • A rare diamond.

  • No.

  • Diabetes is a disease in which glucose or sugar levels in our blood remain high.

  • Is it higher than the Statue of Liberty?

  • No.

  • Most of our food is converted into glucose and released into the bloodstream.

  • Then, our pancreas makes insulin.

  • Insulin helps glucose get into the cells.

  • However, in some people, the insulin production is inadequate or it is not used well.

  • Hence, glucose stays and builds up in the blood.

  • Increasing the blood glucose level and thus, causing diabetes.

  • There are three main types of diabetes.

  • Diabetes type 1 occurs when our immune cells destroy the cells in pancreas which make insulin.

  • Resulting in less or no insulin production.

  • Diabetes type 2 occurs when pancreas cannot produce enough insulin.

  • Our bodies cannot use it well.

  • Gestational diabetes occurs in pregnant women.

  • Diabetes can lead to blindness, kidney failure, heart attacks, etc.

  • Hence, diabetic people should always maintain their blood glucose levels.

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What exactly killed the Dinosaurs? | #aumsum

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    AumSum posted on 2019/04/08
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