Showing posts with label Soil. Show all posts
Showing posts with label Soil. Show all posts

Sunday, February 17, 2013

How does A Plant Make Its Food?

Plant

Green plants make food in their leaves in a special food-making process called “photosynthesis.”

Green plants make food in their leaves in a special food-making process called “photosynthesis” (pronounced foe toe SIN three siss), a word meaning “putting together with light.”

A leaf manufactures food by taking carbon dioxide from the air and water from the soil and changing them into simple sugars.

To do this, it also needs sunlight and green plant material called “chlorophyll.”  This name means “leaf green,” and is the material that gives plants their green color.

The chlorophyll uses the energy of sunlight to change the carbon dioxide gas and water into sugar.

Once the sugar is made, the plant changes it into starch and other foods it needs to grow.  To make some foods it needs minerals from the soil.

Some plants, such as mushrooms and mistletoe, have no leaf green, and cannot make their own food.  They must live on food green plants have made.–Dick Rogers

Sunday, June 17, 2012

Why does the leaning Tower of Pisa lean?

The tower leans because it is slowly sinking in the soft ground.  The Leaning Tower of Pisa is a famous bell tower at Pisa, Italy.  The tower tips so far to one side that it looks as though it would fall over.  But it has been leaning for over 600 years!
Tower of Pisa

Why does it lean?  Of course, it wasn’t supposed to lean when it was built.  Yet it began to lean long before it was finished.

Builders began to work on the tower in 1174.  The stone foundation was not built on time enough ground to support the heavy marble tower and it began to sink unevenly into the soft soil.

But the builders went on adding story after story until the tower was 180 feet tall.  Since it was finished it has leaned a little more as the years went by.

Even today little by little the tower continues to tilt more each year.  It is now leans over 17 feet to one side.  Some people estimated that the tower will topple over within the next 100 years. – Dick Rogers