How did cells evolve?

The central criteria for living cells are a membrane capable of separating the inside of the cell from its surroundings, genetic material capable of being reproduced, and the ability to acquire and use energy (metabolism). The Miller-Urey experiment demonstrated that organic molecules, including genetic material, could arise abiotically. Phospholipids, the molecules that comprise all cellular membranes, can spontaneously form spheres when exposed to water. Although no one knows exactly how living cells evolved, these data demonstrate how a part of the scenario may have unfolded.

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