The Endosymbiotic Theory
The theory of Endosymbiosis explains the origin of
chloroplasts and mitochondria and their double membranes.
This concept postulates that chloroplasts and mitochondria
are the result of years of evolution initiated by the
endocytosis of bacteria and blue-green algae.
According to this theory, blue green algae and bacteria
were not digested; they became symbiotic instead.
Endocytosis is when a substance gains entry
into a cell without passing through its cell membrane.
A cell's plasma membrane invaginates
and fuses to lock foreign material inside.
An intracellular vesicle is formed as a result.
The ribosomes of the inner structure (in chloroplasts and
resemble prokaryotic ribosomes.
cell "engulfs" A
prokaryotic cells the other cell can be found inside
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