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| Sections | |||
|---|---|---|---|
| Prokaryote Cell Structures | 24 mins | 0 completed | Learn |
| Prokaryote Reproduction and Gene Exchange | 17 mins | 0 completed | Learn |
| Prokaryote Metabolism and Ecology | 16 mins | 0 completed | Learn |
| Prokaryote Lineages | 9 mins | 0 completed | Learn |
Oxygen concentration of 1% of 1 billion years ago increased to the present level of 21% because of photosynthetic activity of
a. fungi
b. cyanobacteria
c. plants
d. protists
e. animals
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