Question

why are the miller-urey experiments essential to the theory of evolution?
they showed that life can only come from life.
they showed that electricity can create life.
they showed how organic molecules could be made from earths early atmosphere.
they showed the role that natural selection played in the evolution of modern day organisms.

Explanation:

The Miller - Urey experiment simulated the conditions of Earth's early atmosphere. They used a mixture of gases (believed to be present in the early atmosphere like methane, ammonia, hydrogen, and water vapor) and applied an electric discharge (simulating lightning). The result was the formation of organic molecules such as amino acids. This was important for the theory of evolution as it showed a possible mechanism for the origin of organic compounds from inorganic precursors, which is a key step in the chemical evolution that could have led to the origin of life.

• Option 1: The experiment was about the formation of organic molecules from inorganic ones, not about the concept of life only coming from life (biogenesis).
• Option 2: The experiment did not show that electricity creates life. It showed the formation of organic molecules.
• Option 4: The Miller - Urey experiment was about chemical evolution (formation of organic molecules) and not about natural selection (which is a biological process in the evolution of organisms).

Answer:

They showed how organic molecules could be made from Earth’s early atmosphere.