Name: 為什麼血型很重要？| 為什麼血型很重要？ (Why do Blood Types matter? | #aumsum)
Uploaded: 2021-01-14T08:20:47.000Z
Duration: 4 min 15 s
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轉承詞

Usually, our blood is classified into 8 types, namely.

A positive, A negative, B positive, B negative.

AB positive, AB negative, O positive and O negative.

Presence, absence or combination of specific antigens on our red blood cells.

If we have A antigen, then our blood type is A.

If we have B antigen, then our blood type is B.

If we have both antigens, then our blood type is AB.

And lastly, if we neither have A nor B, then our blood type is O.

The positive and negative factor is determined by the RhD antigen.

If we have RhD antigen, then we are Rh-positive, otherwise we are Rh-negative.

But what is the use of these blood types?

Our immune system produces antibodies against the antigens we don't have.

So, during transfusion, if wrong blood is injected.

Our antibodies will recognize the unknown antigen.

This can cause transfused blood to clot which can be potentially fatal.

In order to deliver oxygen and nutrients.

Our heart pushes blood through tubes called blood vessels.

As the blood moves, it exerts force on the vessels' walls.

The measurement of this force of blood on the walls is called blood pressure.

About 120 over 80 millimeters of mercury or slightly below it.

It is because our heart is constantly contracting and relaxing.

Our heart contracts to push the blood through arteries.

So, the bigger number indicates the systolic blood pressure.

Whereas during diastole, our heart relaxes, decreasing the pressure.

So, the smaller number indicates the diastolic blood pressure.

Blood rain has red colored water droplets.

Brownish dust and sand carried by storms mix with water droplets in clouds.

In Kerala, red spores of algae called Trentepohlia Annulata.

Got carried by wind and mixed with water droplets, causing blood rain.

While, in Zamora, Haematococcus Pluvialis algae got caught in rainclouds.

Got stressed and produced a red pigment called astaxanthin.

Because everyday it bathes using red paint.

A liquid called plasma, red blood cells, white blood cells and platelets.

However, the color of our blood is basically because of red blood cells.

Each of the red blood cells contains hemoglobin.

The interaction between them gives our blood its red color.

Moreover, like human beings, not all animals have red color blood.

This is because the blood of some animals.

Such as octopuses, spiders, etc. has hemocyanin instead of hemoglobin.

Hemocyanin is a copper containing protein.

When hemocyanin binds with oxygen, their interaction gives the blood a blue color.

The blood of some lizards has biliverdin instead of hemoglobin.