Mitochondria or organelles located in the cytoplasm that are responsible for energy transformation in a cell. After the 1940s, it was observed that mitochondria contain their own genes. This observation contradicts evidence stated in which hypothesis?

Answer 1

The observation that mitochondria contain their own genes contradicts the "Endosymbiotic Theory" in its earlier formulations. The Endosymbiotic Theory proposes that mitochondria (and chloroplasts) originated from free-living prokaryotic organisms that were engulfed by ancestral eukaryotic cells. Initially, it was thought that these organelles completely lost their own DNA and became fully dependent on the host cell's nuclear genome for their functions.

However, the discovery that mitochondria retain their own DNA suggests that they have not completely lost their autonomy and support the idea that they are indeed remnants of once-independent prokaryotes. This finding challenges the earlier assumptions that mitochondria were completely integrated into the host cell genome, highlighting their evolutionary significance and the complexity of their relationship with the host cell.