Can you guess the title of my next video?

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Write your guess in the comments section below.

Why is space black?

Coz somebody forgot to pay the electricity bill!!

Naahhh!!

Our sun is a huge star which emits a tremendous amount of light.

However, like our sun, there are so many stars in the universe that counting them is almost impossible.

So, if there are so many stars, the space shouldn't be black or dark, right?

Absolutely!!

However, this is not the case.

According to a study, the space appears black because the universe is expanding.

This expansion is causing the visible light emitted by the stars to stretch out so much that when it reaches our eyes.

They cannot detect it.

As our eyes cannot detect any visible light, the space appears black to us.

Moreover, light has a specific speed limit.

So, light from far far away stars has not even reached us.

Thus, the space appears black.

Why do we yawn?

Human beings, including some animals yawn.

What??

Animals also yawn!!

Absolutely!!

During yawning, which is also called oscitation, we take a deep breath of air.

Hence, a theory suggested that it helps our body bring in more oxygen and give out carbon dioxide.

However, it is incorrect.

A prevailing research suggests that yawning regulates our brain's temperature.

Our brain works best at certain temperatures.

But when we perform various activities throughout the day, our brain gets exhausted and sleep deprived.

Both exhaustion and sleep deprivation increase our brain's temperature.

Hence, to cool it down, we yawn.

While yawning, we stretch our jaw and propel blood through blood vessels to the brain.

Along with this, we inhale air through our mouth and nose.

Air cools the blood going to the brain which in turn decreases our brain's temperature.

How does blood clot?

With the help of glue!!

Not at all!!

Our blood consists of red blood cells, white blood cells, platelets, clotting factors, etc. suspended in a liquid plasma.

Hey!!

I too have a plasma, look!!

Oh!!

Please listen!!

Usually, when a blood vessel gets ruptured and we bleed, our blood begins to form a clot.

First, the platelets start sticking to the broken vessel and each other, thus forming a loose plug.

But this plug is not enough to stop bleeding.

Hence, the clotting factors take part in a complex chain of chemical reactions and create fibrin strands.

These strands criss-cross one another and create a mesh that tightly holds the loose plug together and makes it strong.

Red blood cells and white blood cells also get trapped in the mesh.

Thus creating a blood clot that completely stops bleeding.

What is a cataract?

It may be a cat's nickname!!

Nooo!!!

A cataract is an eye disease.

How does it form??

Wait!!

I'll explain!!

Each of our eyes consists of a transparent lens.

Is it similar to my camera lens??

Absolutely!!

Our eye lens is made up of water and protein.

They are arranged in such a way that keeps the lens clear, and lets light pass through it.

Hence, a sharp image is formed on the retina.

However, as we age, the protein begins to clump together, making the lens cloudy.

This clouding of our eye's natural lens is called a cataract.

In such situations, when light from an object enters our eye, the clumped protein blocks or scatters the light.

As a result, a blurred image is formed on the retina, thus making it hard to see.

Topic: Breathing

Why do we get hiccups?

Easy peasy!!

We get them when our friends think of us!!

No!!

We get hiccups mainly because of our diaphragm.

Diaphragm is a dome shaped muscle between our lungs and stomach.

It generally works perfectly.

Just like me, right??

Nah!!

When we inhale, our diaphragm contracts helping us take in air into the lungs.

When we exhale, it relaxes, helping us give out air.

However, sometimes this contraction does not happen properly.

One of the reasons is excess eating.

Eating too much too quickly causes our stomach to swell, causing discomfort to our diaphragm.

Due to this, our diaphragm contracts irregularly in a jerky way making us suck air suddenly.

This air rushes through our voice box, making the vocal cords to close suddenly, creating a hiccup.