It's AumSum Time.
Why do we get canker sores?
Because I cheat on my diet.
No.
Canker sores are painful ulcers that form inside our mouth.
Although no one exactly knows what gives rise to canker sores.
Researchers suspect that they are caused.
By a combination of factors which include mouth injuries.
Spicy and acidic foods, chocolates, stress.
Hormonal changes, deficiency of Vitamin B-12, etc.
But do you know how these sores are formed?
According to a study.
Our immune system is responsible for these painful sores.
When we get an injury.
Our immune cells release a messenger protein called tumor necrosis factor alpha.
One of the functions of this messenger protein.
Is to kill damaged cells around the injured area.
However, in case of canker sores.
The immune cells produce excess tumor necrosis factor alpha.
Which begins to kill the surrounding healthy cells as well.
Causing inflammation and thus, creating a canker sore.
Topic: Human hair.
Why do we get goosebumps?
To burst balloons.
Nope.
Goosebumps served a purpose for our ancestors who had a lot of hair on their body.
When our ancestors felt cold, their adrenal glands produced adrenaline.
Adrenaline caused the arrector pili muscles.
Which are attached to the hair follicles to contract.
Creating shallow depressions on the skin surface.
And making the hair stand straight up, thus causing goosebumps.
The straightened hair trapped more air.
Which prevented their body heat from escaping and hence, kept them warm.
Also, when our ancestors felt afraid of any animal.
The adrenaline made their hair stand up, making them look bigger.
And thus, scared their attacker.
Ya dude.
It scares me too.
Now, as this characteristic of goosebumps is inherited by us.
We also get them during strong emotions or when it is cold.
Topic: Motion sickness.
Why do we get car sickness?
Because some cars are haunted.
No.
According to a prevailing theory.
Car sickness occurs because of mismatched or conflicting sensory signals.
In a moving car, our eyes see that the car seats are not moving.
Thus informing our brain that we are stationary.
However, the inner ear which detects motion notices the turns and bumps in the road.
And tells our brain that we are moving, thus creating a sensory mismatch and making us carsick.
But why do we vomit?
During human evolution when there were no vehicles.
Only the intake of foods containing neurotoxins made our brain receive conflicting signals.
Now, the only way to remove these neurotoxins was to vomit.
Hence, in the present time, when our brain receives such mismatched signals.
It thinks that there is some neurotoxin in our stomach.
Thus, it induces vomiting.
Topic: Human hair.
Why do we get white hair?
Because we cannot get blue hair.
No.
Our hair is basically made up of keratin, a colorless protein.
Hence, before our hair comes out of the skin, it is almost white.
How's that possible??
I had black hair during childhood.
Don't worry.
I will explain!!
Our hair grows from hair follicles.
A hair follicle contains melanocytes which produce melanin.
Melanin is injected in the keratin cells during the growth of our hair.
This melanin gives color to our hair.
Now, the color of our hair is dependent on the type of melanin injected.
Eumelanin makes our hair black or brown while pheomelanin makes our hair red or blond.
However, as we grow old, the melanocytes decrease the production of melanin.
Thus, less melanin is injected in hair, causing them to eventually turn white.