The Very First Cell

The Earth is billions of years old and was once a very hostile place. Eventually, a single cell was formed that evolved and reproduced. What conditions produced this first life on Earth? Biology - Cells And DNA - Learning Points. Evolutionary Theory suggests that all forms of life evolved from one ancestor - the first cell. 4.5 billion years ago, conditions on Earth were similar to that of Venus, with very little oxygen. It is thought that hydrogen, methane and ammonia in the Earth's early atmosphere combined with the oceans to form a pre-biotic soup. Exposed to ultraviolet rays of the Sun, the pre-biotic soup reacted to form organic compounds such as DNA - the building blocks of life. A Twig Context Film. Reinforce and extend the learning required by the curriculum. Twig’s context films show abstract concepts in action in the real world.