Pikaia Was a Swimming Chordate Whose Fossils Are Found in the

question 18

Multiple Choice

Pikaia was a swimming chordate whose fossils are found in the

• A) Tommotian fauna.
• B) Burgess Shale.
• C) Rocky Mountains of Colorado.
• D) new fossil sites of China.

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Definitions:

Secondary Circular Reaction

A stage in Piaget's theory of cognitive development where infants (4-8 months) repeat actions to get desired outcomes, showing the beginning of intentional behavior.

Tertiary Circular Reaction

A concept in cognitive development referring to a stage in Piaget's model where infants 12-18 months old purposefully experiment with different actions to observe outcomes.

Holophrases

Single-word expressions used by infants that convey a complete thought or idea.

Vocabulary

The set of words known and used by a person or within a particular language.