Stanley Miller and Harold Urey carried out some experiments to see, “ If substances made by living things could be formed in the conditions that had existed on the early Earth.” They had sealed a mixture gases like water, methane, hydrogen and ammonia over a pool of water (which was representing the ocean). They sealed these substances in a flask. They simulated the conditions thought to have been in the early Earth's atmosphere, such as lightning. They heated the flask to make the water evaporate. This formed water vapour. Shortly after that electric sparks were passed through the mixture of water vapour and gases which simulated as lightning. After one week the contents that were found were several organic amino acids, which are one of the main elements of protein. They concluded that there were many organic compounds that could be formed in the conditions of the early Earth's atmosphere after they found the organic amino acids. The controversy relating the Miller Urey experiment is that some people say that they used the wrong acids, which is why they got some really good results. When the test was tried again it did not work. This is why some people feel that it was controversial. The Miller-Urey experiment supported the theory of the primordial soup, which is the idea that complex chemicals that are needed for living things could be produced naturally on the early Earth.

The Earth is made up of four distinct layers:

We get all the materials we need from three main sources. Earth’s crust provides us with rocks. There are three types of rock:

We can find many materials in the ocean including salt, sand, gravel, copper and iron, as well as being able to be drilled for oil

The Atmosphere provides us with materials such as gases. These gases include oxygen, nitrogen and water vapor.

The earth is a sphere consisting of four main layers.