Question

what is the purpose of fingerprints?
Why do we laugh?
Why do we dream?
Why do we yawn?
Plz answer all of them
don't say search it up on google plz

Answer 1

Scientists have long reasoned that fingerprints help humans grip objects by creating friction, since a few primates and tree-climbing koalas also have fingerprints. But a new study found that if fingerprints help people grip things, it's not because they vcreate
more friction
As far as we know, no one has found what parts of the brain causes laughter. According to current research various parts of the brain are involved when someone laughs and research is ongoing.

Researchers have previously discovered, sadness, anxiety, and other emotional responses come from specific parts of the brain, yet laughter seems to come from several parts of the brain through a nerve circuit running through many regions of the brain.

I wonder sometimes if the researchers have a laugh and enjoy themselves as they experiment and strive to discover how laughter works? When someone discovers the cause of laughter, perhaps there will be laughter pills available to treat depression? I don’t know but it’s interesting to think of the ramifications and uses once researchers discover the exact cause of laughter and learn how to trigger genuine laughter in someone.
Dreams are hallucinations that occur during certain stages of sleep. They're strongest during REM sleep, or the rapid eye movement stage, when you may be less likely to recall your dream. Much is known about the role of sleep in regulating our metabolism, blood pressure, brain function, and other aspects of health
Yawning helps to cool your brain down from that clotting. Another reason you may yawn is because the body wants to wake itself up. The motion helps stretch the lungs and their tissues, and it allows the body to flex its muscles and joints. It may also force blood toward your face and brain to increase alertness.

You yawn when you’re:

because

Seeing someone else yawn:

when you’re in the same environment as them, you’re exposed to the same temperature

Answer 2

We all have ridges in our hands and all of them have their unique pattern. Their prints are used as identity and for security purposes.

Laugh is altered in different situations by brain mechanics. It is little known how brain alters pur laughing.

When sleeping, our brain constantly needs to work and hence it hallucinates varieties of things.

We yawn when we get bored. Sometimes, we breath so slowly and oxygen lacks for our brain. So, brain sends signals to yawn. Yawning fulfill the need of enough oxygen.