OBJECTIVE LIFE SCIENCE
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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prokaryotic organisms, eukaryotic organisms, multi-cellular organisms
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eukaryotic organisms, prokaryotic organisms, multi-cellular organisms
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multi-cellular organisms, prokaryotic organisms, eukaryotic organisms
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prokaryotic organisms, multi-cellular organisms, eukaryotic organisms
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Detailed explanation-1: -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. The signals consisted of a type of carbon molecule that is produced by living things.
Detailed explanation-2: -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-3: -The first fossils of prokaryotic (bacterial) cells are known from 3.5 and 3.4 billion years ago. These bacteria were photosynthetic (although non-oxygen producing) so it is likely that simpler non-photosynthetic bacteria evolved prior to this (Schopf, 1987; Beukes, 2004).