Question

The earliest cellular forms of life were believed to be

Answer 1

It appears that life first emerged at least 3.8 billion years ago, approximately 750 million years after Earth was formed (Figure 1.1). How life originated and how the first cell came into being are matters of speculation, since these events cannot be reproduced in the laboratory. Nonetheless, several types of experiments provide important evidence bearing on some steps of the process.

Answer 2

Bacteria.

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