Which Statement Best Describes Why the Cambrian Explosion Was Important

question 13

Multiple Choice

Which statement best describes why the Cambrian explosion was important?

• A) because plant and animal fossils were found together for the first time
• B) because there was an explosion in ecological diversity among animals
• C) because good fossils from this period are available to study
• D) because there was an explosion in animal abundance

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Definitions:

Brainstem

The part of the brain connecting the spinal cord with the forebrain and cerebrum, responsible for controlling several basic life functions.

Dorsal Raphe Nucleus

A nucleus located in the brainstem involved in the release of serotonin and implicated in the regulation of mood, sleep, and anxiety.

Learned Helplessness

An instance where a person is overwhelmed by feelings of helplessness, caused by either a distressing event or continual lack of success.

Contingency Blocking

A phenomenon in classical conditioning where a previously learned association prevents the learning of a new association.