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2.11 Origins of Cell Compartmentalization

#eukaryoticcells

#prokaryoticcells

#endosymbiotictheory

⏱️  1 min read

written by

Tejas Bhartiya

tejas bhartiya

September 25, 2020


The endosymbiotic theory is the current theory of how eukaryotic membrane-bound organelles existed in eukaryotic cells.

The endosymbiotic theory states that an early ancestor of eukaryotic cells engulfed a prokaryotic cell, and the prokaryotic became an endosymbiont, a cell living in another cell. These smaller cells were capable of producing extra energy for the other cell, leading to a selective advantage.

Overtime, cells with an extra cell inside were able to become more able to survive and reproduce quickly. The eukaryotic cell was born!

While prokaryotes generally lack internal membrane bound organelles, they still have internal regions with specialized structures and functions. These regions are just not defined by outer membranes.

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Image courtesy of WikiMedia Commons.

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