Oxygen (O₂) in Earth's Atmosphere Was

question 139

Multiple Choice

Oxygen (O₂) in Earth's atmosphere was

• A) generated by photosynthetic cyanobacteria by oxidation of water.
• B) generated abiotically.
• C) generated by nonphotosynthetic bacteria.
• D) present in high amounts before the origin of life.
• E) present in low amounts when larger eukaryotes evolved.

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Definitions:

Economic Question

Fundamental questions that address the allocation of resources and the distribution of goods and services in an economy.

Pure Capitalism

An economic system purely driven by market forces with minimal governmental intervention, where private individuals and firms control the production and distribution of goods.

Central Planning

An economic system where key decisions about production, distribution, and consumption of goods and services are made by the government or a central authority.

Shift Inward

A situation in economics where the supply curve moves towards the origin, indicating a decrease in supply at every price level.