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:

Preoperational Thinking

A stage in cognitive development where children from about 2 to 7 years of age are able to use language and symbols but not capable of logical reasoning.

Formal Operational Thinking

A stage in Piaget's theory of cognitive development where individuals develop the ability to think abstractly, logically, and systematically.

Overtly Physical Schemas

Cognitive structures that involve understanding the world through physical interaction and movement, often related to early childhood development.

Spatial Perspective Taking

The cognitive ability to understand and interpret the spatial relations between objects from different viewpoints.