OBJECTIVE LIFE SCIENCE
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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chemoautotrophs
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eukaryotes
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methanogens
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photoautotrophs
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Detailed explanation-1: -Photoautotrophs must have evolved before aerobic organisms evolved. ALL eukaryotes have mitochondria, but only plants of chloroplasts!!!
Detailed explanation-2: -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.
Detailed explanation-3: -Bacteria were the first organisms to appear on the earth. At that time the environment was devoid of oxygen. Hence, these first bacteria were anaerobic and they were also heterotrophic due to lack of photosynthetic activity.
Detailed explanation-4: -The first organisms to evolve were prokaryotes, and they remain abundant and widely distributed in the modern world.
Detailed explanation-5: -So the correct answer is “Cyanobacteria".