Types of Wars
Civil wars are fought between citizens of the same country, and are fought within the country.
If citizens of a country disagree about the policy or leader, they may fight a civil war.
A world war is fought when countries form?alliances, and these?alliances fight each other.
A world war involves many or most of the world's most powerful countries.
There were 2 world wars in the 20th century.
Terrorism?involves groups of individuals rather than countries.
Terrorists may come from different countries, and they may share the same?beliefs.
Terrorists often use?car bombings?and?suicide attacks?on innocent people.
A terrorist attack can happen at any time and any place.
An?invasion?occurs when one country attacks another.
It sends its army into the other country, and attempts to take control.
One of the most famous invasions was when France invaded Russia in 1812.
A defensive war occurs when a country is attacked and needs to defend itself.
Most countries have a military, so that it can defend itself if it's attacked.
When France invaded Russia in 1812 the Russian army fought a defensive war and defeated the French army.
Throughout history there have been many invasions.
Biology Terms
A cell is the basic?unit?of life.
The cell is the smallest structure that can live and reproduce.
Cells grow and develop, reproduce and?interact?with the environment.
Photosynthesis?is one of the most important biological processes.
It allows plants to?capture?and use light as?an?energy source.
Photosynthesis is the process of converting light energy into chemical energy.
A virus is a small biological structure that attacks and enters cells.
Once inside a cell, a virus reproduces and makes many copies of itself.
Some?diseases such as?influenza?are viruses.
Bacteria are one-celled forms of life that are all around us.
Although they have a single-cell structure, they are very important.
Many bacteria are inside us and help us digest our food.
DNA is a complex?molecule?that stores information and can make copies of itself.
Nearly every cell in a person's body has the same DNA.
The information stored in DNA tells cells what to do, and is necessary for reproduction.
Many bacteria are?inside?us and?help?us?digest?our food.
