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2015/04/20

MONTESSORI BIOLOGY : The Gift of The First Plants




The Gift of The First Plants

The first plants changed the entire history of
 the earth. They made it possible for all future
 life to develop. They not only changed the
 face of the earth, they even changed the 
atmosphere surrounding the earth. 



At first, the earth's atmosphere consisted 
of a mixture of gases: hydrogen, ammonia, 
methane and water vapor. Later, after the great
 rains, a new atmosphere came into being. 
This atmosphere consisted of water vapor,
 Nitrogen and Carbon Dioxide.



Living things could not emerge from the oceans 
onto the land. Even if they could have breathed 
this atmosphere they would probably have been
 destroyed by the burning ultraviolet rays of the sun. 



Carbon Dioxide, though is soluble in 
water. Some of the Carbon dioxide became 
dissolved in the oceans. The first plants used 
this dissolved Carbon Dioxide to make their 
food by photosynthesis. At the same time, 
they released oxygen into the atmosphere.



Very, very gradually, the Carbon Dioxide in 
the atmosphere was consumed by the plants and
 then replaced by the Oxygen that was released. 



Once again, a new atmosphere came into being. 
This was the third atmosphere in the history of the 
earth. Nearly 4/5 was Nitrogen, and nearly 1/5
 was Oxygen. Only a little was Carbon Dioxide, 
but it was enough for the plants.



Then another remarkable change took place. 
High in the atmosphere some of the Oxygen turned
into a special form of Oxygen called Ozone. 



The Ozone acted like an invisible blanket 
around the earth, preventing most of the 
ultraviolet rays of the sun from reaching the 
earth's surface. This is important as ultraviolet 
rays are harmful to most life forms.

www.hptware.co.uk/images/prehistoric3.jpg

At last, perhaps 350 million years ago, living things
 could safely come out of the oceans onto the land.
 Simple plants and tiny simple animals crept
 out onto the shores and began the task 
of making the earth green and fertile.



Life on earth was made possible by those 
first plants which developed photosynthesis.


   
 Pinegreenwoods Montessori 
Montessori Biology