EVOLUTION
THE ORIGIN OF LIFE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Photosynthetic bacteria, anaerobic bacteria, cells with organelles, multicellular organisms
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anaerobic bacteria, photosynthetic bacteria, cells with organelles, multicellular organisms
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Cells with organelles, anaerobic bacteria, photosynthetic bacteria, multicellular organisms
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multicellular organisms, photosynthetic bacteria, anaerobic bacteria, cells with organelles.
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Detailed explanation-1: -Evolution of cells. Present-day cells evolved from a common prokaryotic ancestor along three lines of descent, giving rise to archaebacteria, eubacteria, and eukaryotes.
Detailed explanation-2: -The first eukaryotic cells-cells with a nucleus an internal membrane-bound organelles-probably evolved about 2 billion years ago. This is explained by the endosymbiotic theory. As shown in the Figure below, endosymbiosis came about when large cells engulfed small cells.
Detailed explanation-3: -Development of a flexible cell surface, cytoskeleton, nuclear envelope, and the acquisition of cellular organelles such as mitochondria and chloroplast through the establishment of an endosymbiotic relationship with an aerobic prokaryote, were all early steps in the evolution of eukaryotic cells from the prokaryotes.
Detailed explanation-4: -Abstract. Eukaryotes arose about 1.6 billion years ago, at a time when oxygen levels were still very low on Earth, both in the atmosphere and in the ocean.