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Triss [41]
3 years ago
9

Oxygen first entered Earth's atmosphere when one-celled organisms resembling modern cyanobacteria began to carry out the process

of _____.
A fossilization
B evolution
C photosynthesis
D erosion
Biology
2 answers:
Mekhanik [1.2K]3 years ago
8 0

Answer: C. Photosynthesis

Cynobacteria, or blue green algae were the first primitive single celled organisms on planet earth, that were capable of performing photosynthesis on planet Earth. The cynobacteria were responsible for producing oxygen by oxidizing water to evolve oxygen, using sunlight and carbon dioxide present in the atmosphere. These primitive organisms had chloroplast to capture the sunlight.




Eddi Din [679]3 years ago
7 0
Answer is C since since its algae or blue algae 
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Answer:

faced a struggle for survival

Explanation:

The woolly mammoths became extinct, unlike the other species, because the woolly mammoths faced a struggle for survival due to changing of environmental conditions. Global warming is the main cause of extinction of woolly mammoth which destroy their habitats about 10,500 years ago. The environmental conditions are not favourable for them so they faced struggle for survival which causes extinction of woolly mammoth.

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Which of the following is a synonym for bias?
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B --------------------
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tino4ka555 [31]

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A rise in blood carbon dioxide concentration.

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