Question

The paragraph describes mitochondria and chloroplasts. Which sentence in the paragraph provides the strongest evidence for the endosymbiotic theory of the origin of eukaryotes? Mitochondria and chloroplasts are organelles of eukaryotic cells.Mitochondria are involved in energy generation and are present in almost all eukaryotic cells. Chloroplasts are involved in photosynthesis and are found primarily in plant cells. In both organelles, reactions involved in the transfer of energy take place along the organelle's folded inner membrane. Both organelles can direct their own replication by splitting through a process similar to binary fission.

Answer 1

The answer is; E

This shows that these organelles were once free-living organisms with their own mechanisms for reproduction which they have retained even after years of symbiotic relationship with the higher organisms. During their duplication, they also replicate their own DNA. Their DNA does not have histones (as opposed to the DNA in the nucleus of their host eukaryotic cell) similar to that of simple organisms such as bacteria.

Answer 2

The correct answer is both organelles can direct their own replication by splitting through a process similar to binary fission.

Step-by-step explanation:

Endosymbiotic theory explains the formation of organelles like chloroplast and mitochondria which evolved miliion of years ago by engulfing the phototrophic and chemotrophic bacteria respectively.

Evidences that support their endosymbiotic relation is that they

1. Both chloroplast and mitochondria contains their own genetic material-DNA.

2. They divide with the same mechanism used by the bacteria that is binary fission to form two daughter cells.They have their own prokaryotic replication machinary to start replication. Therefore, fission and replication are coordinated with each other.

Thus, organelles divide by binary fission is the correct answer.