Which of the Following Factors Involved in the Cambrian Explosion

question 41

Multiple Choice

Which of the following factors involved in the Cambrian explosion was likely not due to a changing ocean chemistry?

• A) increased oxygen levels
• B) increased nutrients from soil erosion
• C) evolution of genetic toolkit
• D) evolution of biomineralization

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Definitions:

Sympathetic System

Part of the autonomic nervous system that prepares the body for 'fight or flight' responses, increasing heart rate, dilating airways, and mobilizing energy.

Reuptake

The process by which neurotransmitters are taken back into the neurotransmitter vesicles in the nerve cells after they have been released.

Serotonin

A neurotransmitter associated with mood regulation, digestion, sleep, and other bodily functions, playing a key role in preventing depression and regulating anxiety.

Axon Terminal

The endpoint of an axon or nerve fiber, where it makes synaptic connections with another nerve cell or muscle cell.