What Led to the Increase in Oxygen Levels in the Atmosphere

question 72

Multiple Choice

What led to the increase in oxygen levels in the atmosphere on primitive Earth?

• A)the first photosynthetic reactions
• B)photosynthetic cells that used water and not H₂S as a source of electrons
• C)the development of cellular respiration pathways in cells
• D)the use of glycolysis in cells
• E)photosynthetic pathways that stripped oxygen off of carbon dioxide and retained only the carbon in subsequent steps

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Definitions:

Production Capacity

The maximum output that an organization can produce in a given period under normal working conditions, considering available resources.

Work Stoppages

Occurrences when employees halt work, often due to labor disputes or strikes, affecting productivity and operations.

Direct Materials Price Variance

The difference between the actual cost of direct materials and the expected standard cost, indicating how well a company controls its material costs.

Controllable Variance

Controllable Variance is the difference between actual spending and budgeted amounts that management could control or influence directly.