The First Significant Injection of Oxygen into the Environment Was

question 7

Multiple Choice

The first significant injection of oxygen into the environment was the result of

• A) prokaryotic photosynthesis using photosynthetic pigments.
• B) prokaryotes using organelles, which detoxified oxygen.
• C) photosynthesis by chloroplasts in eukaryotes.
• D) energy metabolism in mitochondria of eukaryotes.
• E) improved gas and nutrient exchange allowed by the flexible cell membranes of eukaryotes.

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Definitions:

Market Price

The current price at which a good or service can be bought or sold in a particular market.

Long Run

A period in economic analysis where all factors of production and costs are variable, allowing full adjustment to changes.

Weekly Operating Profits

Weekly operating profits describe the earnings a business generates from its normal operations over a one-week period, excluding any income from investments or other non-operational sources.

Short Run

An interval in economic studies where a minimum of one production element remains constant and is unalterable.