1. Analysis of the oldest sedimentary rocks provides evidence for the origin of life. (25)
List the atmospheric gases believed to have existed on early Earth. (3)
The composition of earthy earths atmosphere included water, methane, hydrogen, carbon dioxide, ammonia and nitrogen.
Describe the hypothesised conditions and environment of early Earth. (2)
Earthy earth was hypothesised to have gigantic lakes and oceans, with only a small amount of land above water. It had no ozone layer so it was prone to meteorites and flying space debris. It had volcanoes erupting constantly and no free oxygen in the air. This means that early earth had an anoxic atmosphere.
Relate the conditions on early Earth to the origin of organic molecules. (2)
Organic…show more content… They designed this experiment to observe the possible formation of life. They conducted this experiment by combining ammonia, methane, water and hydrogen in a container. They added an electrical spark to simulate lightening. The let their experiment run for a couple of days and returned to find simple amino acids had been created. Miller and Urey completed this experiment hundreds of times and every time organic compounds were produced. Unfortunately even trying different combinations and compounds no living thing has ever been created from non living things in a laboratory. This supports the theory that the compounds to create life on earth were brought from outer space.
Discuss the significance of Urey and Miller’s experiments in the debate on the composition of the primitive atmosphere. (3)
Urey and Miller’s experiment showed that from inorganic molecules, organic molecules, amino acids to be exact could be formed. This means that if earths composition was like Urey and Miller thought it was, which there is strong evidence to support, organic compounds can be formed. That is life could be formed on earth. Although in a laboratory no living thing has been produced from a non living thing, organic compounds have been produced which is the first step. This could mean that the other elements that help create organic compounds into life could have come from the cosmos (outer space).