Why Are Developmental Biologists So Interested in Studying Echinoderm Embryos

question 22

Multiple Choice

Why are developmental biologists so interested in studying echinoderm embryos?

• A) Echinoderms are primitive chordates.
• B) Echinoderms are the closest living relatives of chordates.
• C) Echinoderms are the only animals with three embryonic germ layers.
• D) Echinoderms, unlike most invertebrates, retain their notochords as adults.
• E) Echinoderms, like chordates, are protostomes.

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Definitions:

Social Adjustment

Refers to the process by which individuals adapt their behavior to meet the demands and norms of their social environment.

Social Play

A type of play involving interaction with peers, important for developing social skills and bonds.

Parallel Play

A developmental stage in early childhood where children play next to each other but do not interact or play together, signaling the beginning of socializing behaviors.

Reflexive Play

A type of play activity that involves spontaneous, unplanned movements and actions, often seen in infants.