Question

Which statement supports the theory that chloroplasts evolved from cyanobacteria?

Answer 1

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Answer 2

The endosymbiotic theory supports that chloroplasts have evolved from cyanobacteria

Answer 3

Following are some of the evidences which support endosymbiotic theory
New plastids are formed only through a process similar to binary fission.
Plastids contain single circular DNA that is different from that of the cell nucleus and that is similar to that of cyanobacteria (both in their size and structure).

Answer 4

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Answer 5

@MangoMania @Abhisar The theory does not suggest that chloroplasts evolved from cyanobacteria. @Abhisar The size of the plastid genome is not all that similar to cyanobacteria; usually it is very reduced. However, it is much closer in size to cyanobacteria genomes than Eukaryotes.

Back to the theory: The theory states that chloroplasts and mitochondria are a result of total phagocytosis without digestion, of a organism that is likely very similar to modern cyanobacteria. This was followed by a series of genome reduction in the phagocytized cells and a series of gene duplication and exchange between the nucleus of the "host" cell and the circular chromosome of the "symbiont" cell.