Explain pieces of evidence that support the theory that mitochondria evolved from bacteria?

Mitochondria are one of the three eukaryotic organelles that have a double membrane (along with chloroplasts and the nucleus), two of which are believed to have evolved from bacteria (mitochondria from Proteobacteria and chloroplasts from cyanobacteria). This structure is different to the majority of eukaryotic membrane-bound organelles, which only have a single membrane (e.g. lysosome, Golgi, endoplasmic reticulum, etc.). Furthermore, mitochondria possess their own DNA in the form of a plasmid. It is very rare for eukaryotes to store their genomic DNA in the form of a plasmid, however, the majority of bacterial DNA is in plasmid form (with bacteria only possessing a single, circular chromosome). These plasmids are of a similar size and structure to true bacterial plasmids, which also supports the endosymbiotic theory. Further evidence includes: mitochondria divide by binary fission, the same as bacteria; cells cannot create new mitochondria if they are removed; the outer membrane transport proteins (porins) are the same in bacteria and mitochondria, as well as membrane composition; protein synthesis within mitochondria is initiated the same way as in bacteria; genetic relationships between mitochondria and bacteria.

Answered by Angus L. Biology tutor

12494 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

What are the 4 stages of aerobic respiration?


Describe how the structure of the renal corpuscle facilitates ultrafiltration.


During the cardiac cycle , there is a delay between the excitation of the atria and excitation of the ventricles. Explain how this is achieved and why this delay is essential.


In which ways are the lungs adapted for efficient gas exchange?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences