Multicellular Organisms Arose Due to ________

question 42

Multiple Choice

Multicellular organisms arose due to ________.

• A) a substantial rise in oxygen levels in earth's atmosphere
• B) a substantial rise in CO₂ levels in earth's atmosphere
• C) the transition from aquatic to terrestrial environments
• D) extinction of unicellular organisms

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Definitions:

Medulla Oblongata

The lower portion of the brainstem involved in autonomous functions such as breathing and blood pressure regulation.

Reticular Formation

A network of neurons located in the brainstem involved in regulating wakefulness, sleep, and various reflexes.

Medulla Oblongata

The lower portion of the brainstem controlling vital autonomic functions such as breathing, heart rate, and blood pressure.

Thalamus

A structure within the brain that acts as a relay station for sensory and motor signals to the cerebral cortex.