The Accumulation of Free Oxygen in Earth's Atmosphere Began with the Origin

question 39

Multiple Choice

The accumulation of free oxygen in Earth's atmosphere began with the origin of ________.

• A) life and respiratory metabolism
• B) photosynthetic bacteria that had photosystem I
• C) cyanobacteria using photosystem II
• D) chloroplasts in photosynthetic eukaryotic algae
• E) land plants

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Definitions:

Ice

A solid state of water that occurs when it freezes, typically at or below 0°C (32°F).

Salinization

The process of increasing salt content in soil, often due to improper irrigation practices, leading to reduced soil fertility and negatively impacting agriculture.

Accumulate

To gather or collect a substance, objects, or information gradually over time.

Moving Soil

Refers to the process of relocating topsoil or substrata from one location to another, often in landscaping and agricultural practices.