Happy 189th Birthday, Gregor Mendel!

Did you see today's google doddle? For those of you who have studied inheritance or genetics might have heard of this name, Gregor Mendel. He is known as the "father of modern genetics".

Here is a biography on Gregor Mendel taken from www.pinkmonkey.com :

"Gregor Johann Mendel was born on July 22, 1822 in Moravia, Austria. He had his early education in a monastery in Brunn, Austria (now Brno in Czechoslovakia) and later studied science and mathematics at the University of Vienna. He graduated in 1840. Mendel returned to the monastery in Brno as a monk. He worked as a teacher of physics and natural science in a Higher Secondary School of Brno during 1854 to 1868. He was appointed abbot of the monastery in 1868 and held this post until his death.

Mendel carried out his legendary experiments on garden pea plants in the monastery garden from 1857 to 1865. He had a clear perspective and worked on the experiments with precision and thoroughness. He published his research paper containing his observations and conclusions in 1866 in the annual proceedings of the Natural History Society of Brunn. These conclusions are now known as Mendel’s Laws. This work is a classic in biology for its elegance and simplicity and ranks amongst the most outstanding biological contributions of all times.

But unfortunately, this work failed to attract the attention of the biologists of that time. Hence, it went ignored for 35 years. One of the possible reasons for such neglect was the inability of the biologists of that time to understand and appreciate the statistical approach adapted by Mendel. Thus, Mendel was left bitterly disappointed, and died an unrecognized death in 1884. 

Sixteen years after Mendel's death, in 1900, Hugo de Vries (Holland), Karl Korrens (Germany) and Von Tschermark (Austria) independently arrived at similar conclusions as those of Mendel. De Vries rediscovered the research paper of Mendel and it was published again in 1901. The experiments on heredity of plants and animals since then have confirmed that Mendel's laws of heredity are applicable to other organisms as well. They form the basis of modern genetics. Hence, Mendel is called The Father of Genetics."

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ARGGHHHH! TOO MUCH PRESSURE!!

Don’t worry peeps…It’s not a stressful topic to learn. In fact, once you've mastered the topic, you can do a magic trick with this air pressure concept. Last week, I showed my students some cool science demos to see the effect of air pressure on an object. You can try these tricks at home but remember NOT TO perform these tricks without adult supervision :) 

1) Crushing a soda can with nothing more than air!

 

HOW DOES THIS WORK?

At first, the soda can was filled with water and air. Then the can was heated to boil the water inside (water changed from liquid to gas). This gas pushed the air inside the can into the atmosphere. When the can was turned upside down and placed in the water, the water vapour condensed creating a partial vacuum. The very low air pressure inside the partial vacuum of the can made it possible for the greater air pressure outside of the can pushed the can and crushed it. This sudden collapsing of an object toward its centre is called an implosion.

2) How to get an egg in a bottle in an “eggciting” way?

HOW DOES THIS WORK?

When the person heats the bottle, it causes the air pressure inside to increase. The egg is then placed in the opening and the air cools, exerting less pressure on the egg than the pressure exerted on the egg by surrounding air in the room. The greater air pressure of the room pushes the egg into the bottle.

 3) Self inflating balloon

  HOW DOES THIS WORK?

A sealed balloon was placed inside a vacuum chamber. As the pressure exerted on the balloon decreases, the balloon expands and takes up the space inside the chamber. When the chamber is opened, the air pressure exerted on the balloon increases and causes the balloon to return to its original size.

So...did you learn anything? How cool was that? Who would've thought learning science could be so much FUN! 8)

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