Amoeba

What are they?

An amoeba is an animal that is single celled ( made up of only one cell ) and was the first animal to be there on the earth.

Habitat and Bodily Functions

They are generally found near wet conditions. Of course, there are many kinds of amoebae present in the earth. There are parasitic ones too.

These animals are recognised by their ability to extend the cytoplasm to form what is a pseudopodia ( meaning false feet ) and is the most primitive of motion. They are not totally useless, small as they are. They are used in research of cells. Each one has a jellylike cytoplasm, that is diffrent from the outer coating. They contain most parts of a normal cell. They have no mouth or anus, they just engulf the food and the waste is thrown out anywhere. They breathe by taking oxygen from the surrounding water. They reproduce by binary fission. They survive hostile environments by forming a protective covering that is thrown off at the right time.

In binary fission, first the nucleus divides into two parts. Then these parts move to the two extreme positions of the cells. Then there is a constriction in the cell body that later grows and divides the cell into two new cells.

From where did they evolve and when?

The first cell was formed owing to complex chemical reaction which took place near water. Since DNA is after all an organic acid, scientists believe that the environment could have caused changes in the DNA which lead to the origin of life.