Researchers have found that mitochondria and chloroplasts in eukaryotic cells have their own DNA. This DNA is different from the
DNA in a eukaryotic cell's nucleus. Chloroplasts and mitochondria use their own DNA and ribosomes to make some organelle-specific proteins. What statement is best supported by this information?
A.
Early eukaryotic cells engulfed prokaryotic cells, which later became mitochondria and chloroplasts.
B.
Mitochondria and chloroplasts could exist outside of modern cells.
C.
Modern cells could exist without mitochondria and chloroplasts.
D.
Early prokaryotic cells engulfed eukaryotic cells, which later became mitochondria and chloroplasts.
B. Early Eukaryotic cells engulfed mitochondria and chloroplasts
Explanation:
Mitochondria and Chloroplast are organelle that are found in cells of higher animals. Chloroplast are found almost exclusively in plants and mitochondria is found in animal cells. The function of these organelles are to produce energy to the cells, and by extension, the organism that they live in.
Unique features of these organelles show that they have their own DNA and divide and multiply on their own. This strongly suggest that they were once free living prokaryotes and were engulfed by larger cells and a symbiotic relationship began.
As time progressed, these prokaryotes did not require all of their genetic information and this was removed from their system. They kept essential genes and regulatory bodies separate that they needed for their maintenance and function that they provide.
2 examples - 1.) in italy, ( limone ) a unique mutation protects them from developing atherosclerosis, 2.)theres mutation in bacteria too, this mutation allows bacteria to survive in the presence of antibiotic drugs, leading to the evolution of antibiotic-resistant strains of bacteria.
