Friday, July 20, 2012

GLOBAL WARMING

What is global warming?

Global warming refers to the environmental condition resulting from Earth retaining too much heat .

Gases such as carbon dioxide, trap heat, and and these gases are being released or sent into the atmosphere at a rapid or alarming rate. As a result of this, the balance of gases in the air is destroyed.

Excess carbon dioxide, which is a hot gas, comes from the fumes generated or given off by factories and motor vehicles.

The destruction of forests for lumber or other uses for mankind, is also a contributing factor to global warming. People sometimes use the  'slash and burn' method to destroy trees. A large amount of carbon dioxide is released into earth's atmosphere when this is done.

Trees supply us with oxygen, and take in carbon dioxide. Therefore, the fewer the trees that are left behind, the less oxygen will be produced.


Read this folder which will help you to understand more about global warming, then take the quiz that follows.

Friday, October 14, 2011

Lines of latitude and longitude


Lines of latitude and lines of longitude are imaginary lines. This means they are not real. They come together to form a grid. This helps us to calculate the grid address of every place on planet earth.

The main line of latitude is the equator and this measures zero degrees. It is the only line of latitude which is a Great Circle. The equator divides the earth into the Northern and Southern Hemispheres.

How materials affect the behaviour of light

Materials affect the behaviour of light in a number of ways.

Take a look at this clip.

Sunday, September 18, 2011

Wednesday, April 27, 2011

The Flower

The flower is the part of the shoot system that enables plants to reproduce.


Tuesday, April 26, 2011

Food Pyramid

Read about the food pyramid.

Look at the interactive food pyramid, then take the quiz.