Changes In The Atmosphere Causing Multicellularity
Beginning of paper
About 2.5 billion years ago, oxygen began slowly to accumulate in the
atmosphere, as a result of the photosynthetic activity of the cyanobacteria.
Those prokaryotes that were able to use oxygen in ATP production gained a strong
advantage, and so they began to prosper and increase. Some of these c ....
Middle of paper
.... the
association of DNA with histone proteins and its organization into a number off
distinct chromosomes, and complex organelles, among which are chloroplasts and
mitochondria. Scientists believe that eukaryotic organisms such as the protists
evolved from the prokaryotes. There are two main theories which describe how
this transition may have occurred. The first is the endosymbiotic theory, or
enosymbiosis, and the other is the autogenous theory, or autogenisis. These two
theories are no ....
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Word count: 471
Page count: 2 (approximately 250 words per page)
