But fortunately for most of us, the immune system is constantly on duty to battle germs that could make us ill. The following discussion questions and activities will help your students learn about how the immune system protects them from germs and illness.
Elephants however, go through six sets of 9lb teeth during their lifetimes, with new teeth growing in to replace old ones that have worn out. An elephants starts with two front teeth that fall out after about a year and are replaced by a set of tusks.
Elephants use their teeth in sequence, not all at once. This means that, at any time, they only have one tooth in each jaw, a total of four. In total, they have 24 teeth: 12 front teeth, called premolars, and 12 back teeth, called molars. When the last molar wears out, the elephant dies because it cannot eat. They can live for about 70 years. But in a zoo or circus, people can keep elephants alive by feeding them soft food.