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  • So springtime is upon us, and the weather is beautiful!

  • Flowers are blooming and people are

  • breaking out their shorts and t-shirts.

  • But, if youre like me, youre miserable,

  • and stuck at home with a runny-nosed and puffy eyes.

  • But why do we have to suffer from the horrible allergies?

  • An allergy is actually a mistake

  • that the immune system is making.

  • Normally we’d make antibodies to fight germs,

  • or recognize germs, but in this case

  • the immune system has made a mistake,

  • it’s making an antibody that recognizes

  • harmless things such as pollens or animal dander.”

  • Inside every allergy sufferer, there lies

  • an immune system that mistakenly produces

  • an antibody known as immunoglobin E.

  • When these unfortunate people breathe in the pollen,

  • the antibody triggers an allergic reaction. But were

  • not just talking about any kind of pollen, here.

  • It’s commonly thought that allergy-causing pollen

  • comes from big, pretty flowers like this, (Big Yellow sunflower image onscreen).

  • But actually, that pollen is too heavy to go airborne.

  • Allergies are cause by pollens from trees

  • and grasses that are small and light

  • enough to be carried by the wind.

  • When the immune system, somebody who’s allergic,

  • recognizes these pollens, the immunoglobin E.

  • activates cells of the immune system, mast cells,

  • and these mast cells will release chemicals

  • that cause allergic reactions.

  • One of the most well-known chemicals that cause reactions is histamine.

  • Histamine is a small organic molecule and how

  • histamine works is as a small chemical messenger,

  • finds a receptor that’s on many, many cells

  • of the body called a histamine receptor

  • and sends that cell a message.

  • For example blood vessels when it binds to that

  • receptor it tells the blood vessel to become leaky,

  • which causes the runny nose that you get or for

  • example they can cause receptors on nerves which

  • the histamine will activate and that gives you

  • the sensation of itchy nose that you

  • might feel during pollen exposure.”

  • So if youre wheezing and sneezing this spring,

  • try to stay indoors early in the morning

  • when there’s more pollen floating around.

  • But if you have to go out there, at least pack

  • some tissues! And maybe some anti-histamines.

So springtime is upon us, and the weather is beautiful!

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B2 中高級 美國腔

為什麼我們會過敏?- 反應 (Why Do We Get Allergies? - Reactions)

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    Eating 發佈於 2021 年 01 月 14 日
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