EVERYDAY SCIENCE

Detailed explanation-1: -Prokaryotes were the earliest life forms, simple creatures that fed on carbon compounds that were accumulating in Earth’s early oceans. Slowly, other organisms evolved that used the Sun’s energy, along with compounds such as sulfides, to generate their own energy.

Detailed explanation-2: -The eukaryotes developed at least 2.7 billion years ago, following some 1 to 1.5 billion years of prokaryotic evolution.

Detailed explanation-3: -The first fossils of prokaryotic (bacterial) cells are known from 3.5 and 3.4 billion years ago.

Detailed explanation-4: -They first appear in the fossil record around 4 billion years ago. Prokaryotes were around for a long, long time before eukaryotic cells appeared around 1.8 billion years ago. This has led us to think that the ancestor of all eukaryotic cells was a prokaryote.

Detailed explanation-5: -The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old.