What is endosymbiotic hypothesis

Question

What is endosymbiotic hypothesis regarding the origin of mitochondria? What are the molecular facts which support the hypothesis? To which other cellular organelles can hypothesis too be exerted?

Answer 1

It is supposed that mitochondria were primitive aerobic prokaryotes which were engulfed in mutualism by primitive anaerobic eukaryotes, obtaining protection from such beings and offering energy to them. Such hypothesis is termed as the endosymbiotic hypothesis on the origin of mitochondria.

The hypothesis is strengthened by certain molecular evidence like the fact that mitochondria contain their own independent DNA and protein synthesis machinery, with their own RNA and ribosome, and that they can self-replicate.

Endosymbiotic theory can be exerted to chloroplasts too. It is assumed that such organelles were primitive photosynthetic prokaryotes since they have their own RNA, DNA, and ribosome and they can self-replicate also.