The Story of Life...and Organisms

1. The earth was formed about 4.8 billion years ago but the first form of life appeared only about 3.8 billion years ago.

2. Swan necked flask experiment by Louis Pasteur demonstrated that life arises from the pre-existing lives.

To answer the origin of life on earth, Oparin and Haldane came up independently with the theory of chemical evolution.

According to this theory:

1. The earth's surface and its atmosphere were very different from what it is today.

2. Life evolved fr…