It's AumSum Time
Why are flies so hard to swat?
Because they can fly.
No.
When we see the world, our eyes send around 60 images or flashes per second to the brain.
Our brain then combines these images, helping us see like this.
The eyes of a fly send 250 flashes per second to their brain.
Meaning, it takes in 4 times more visual information.
Hence, when its brain combines 250 images, one second feels much longer.
Making the fly see in slow motion and allowing it to react much quicker than us.
Now, when we move our hand to swat a sitting fly
Our action seems like a super quick single action to us.
However, owing to the fly's ability to see our action in slow motion
It gets enough time to fly away, even as we are just in the middle of the action.
How is coffee decaffeinated?
Using a vacuum cleaner.
No.
Coffee contains caffeine.
Caffeine boosts our energy and keeps us focused for a short duration.
However, caffeine can also cause headaches, nervousness, etc.
Hence, decaffeinated coffee is a very good alternative.
Now, there are various methods to decaffeinate coffee.
One of them is solvent based method.
In this, green coffee beans are first soaked in hot water for several hours.
This causes caffeine and flavor of coffee to get dissolved in hot water.
Now, in the second step, the green coffee beans and hot water are separated.
Then, using various solvents like methylene chloride or ethyl acetate
Caffeine is removed from this water.
Then this water which still has the flavor of coffee in it
Is added back to the coffee beans so that they reabsorb the flavor.
In this way, coffee is decaffeinated without compromising its flavor.
Why don't penguin's feet freeze?
Because they wear anti freezing socks.
No.
Penguins live in very cold climates and walk on ice.
Hence, penguins have developed certain adaptations
To avoid losing body heat and to protect their feet from freezing.
One of the adaptations includes mechanism called countercurrent heat exchange.
What is that?
Wait, I will explain.
At the top of a penguin's feet, arteries and veins wrap around each other.
Now, when warm blood flows through the arteries to the feet
Much of the heat from the warm blood gets transferred to the cold blood in veins
Which is carrying blood away from the feet.
In this way, penguins do not lose heat from their feet to the ground.
Also, the blood which reaches the feet is just warm enough.
To keep the feet above freezing point, helping the penguin to not get frostbite.
How do fish breathe underwater?
With the help of oxygen cylinders and masks.
No.
Fish breathe underwater using the oxygen that is dissolved in water.
So, do they use a mini vacuum cleaner to absorb oxygen from water?
No.
To absorb oxygen from water, fish use special organs called gills.
Gills are full of blood vessels.
Also, the walls of the gills and blood vessels are very thin.
Now, during breathing, fish take in water through their mouth
And forcefully push it through their gills.
When the water moves through the gills, the dissolved oxygen from water
Passes through thin walls of gills and blood vessels and enters the blood.
Apart from this, waste carbon dioxide present in the blood passes into the water.
Thus, helping fish to breathe underwater.
Eventually, the carbon dioxide rich water is given out from gills.