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Morgarella [4.7K]
2 years ago
11

Scientists infer that oxygen first began to enter Earth's atmosphere after the appearance of

Biology
1 answer:
GenaCL600 [577]2 years ago
8 0

Oxygen entered the Earth's atmosphere after the appearance of the Great Oxidation Event (Great Oxygenation Event). The Great Oxidation is the first mass extinction on Earth.

The Great Oxidation lasted 2.4 to 2.0 billion years ago.

Oxygen appeared on Earth thanks to cyanobacteria using photosynthesis.

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If the black horse is homeozygous, what is its genotype?
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Which of the following is a factor that determines the rate of impulse propagation, or conduction velocity, along an axon?a) len
mihalych1998 [28]

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c) degree of myelination of the axon

Explanation:

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7 0
3 years ago
When elements combine to form compounds what happens to the properties of the original elements?
exis [7]
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Another example is where sulphur has a yellow colour, but iron(II) sulphide has a brownish colour. As we can see, even the physical properties (colours) are completely different.

Therefore, the properties of the original elements are completely changed when they're combined into compounds.





3 0
3 years ago
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