the endosymbiotic theory states that the origin of the eukaryotic organelles are symbiont bacteria which have been engulfed into other larger cells. this was trivial at first fueled by some observations. however, in the past few decades, it is surprising that evidences are accumulating providing evidence for this controversial theory:
a) mitochondria and chloroplasts have their own genetic material different from the information from the nucleus
b) mitochondria and chloroplasts divide in a similar manner as bacteria
c) mitochondria, chloroplasts, the nucleus, and the endomembrane system have double membrane systems the outer of which is similar to the cell membrane and inner more similar in make-up with prokaryotes
d) mitochondria and chloroplasts have 70s ribosomes, bacteria have 70s ribosomes. the ribosomes used by the cells are 80s
recently... centrioles have been found to contain small amounts of DNA. these were suggested as remnants of their origin.
what do you think?
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