What Is The Endosymbiotic Hypothesis About The Origin Of Mitochondria? What Are The Molecular Facts That Support The Hypothesis? To Which Other Cellular Organelles The Hypothesis Can Also Be Applied?
Answers
Answer:
It is presumed that mitochondria were primitive aerobic prokaryotes that were engulfed in mutualism by primitive anaerobic eukaryotes, receiving protection from these beings and offering energy to them. This hypothesis is called the endosymbiotic hypothesis on the origin of mitochondria.
The hypothesis is strengthened by some molecular evidences as the facts that mitochondria have own and independent DNA and protein synthesis machinery, with own RNA and ribosomes, and that they can self-replicate.
The endosymbiotic theory can be applied for chloroplasts too. It is supposed that these organelles were primitive photosynthetic prokaryotes because they have own DNA, RNA and ribosomes and they can self-replicate too.
Explanation:
Both the organelles mentioned in your question, are present in eukaryotic cells.
Both mitochondria and chloroplast have their own circular DNA .
These organelles are also equipped with 70S ribosomes rather than the regular 80S ribosomes of eukaryotes.
Gene expression involves DNA to RNA transcription, and translation of RNA into protein.
Therefore gene expression similar to bacterial system can be regarded as evidence that supports the endosymbiotic theory of origin of eukaryotic cells from prokaryotic cells .