Which of These Might Have Been Observed in the Common

question 4

Multiple Choice

Which of these might have been observed in the common ancestor of chondrichthyans and osteichthyans?

• A) a mineralized, bony skeleton
• B) opercula
• C) bony fin rays
• D) a spiral valve intestine
• E) a swim bladder

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Definitions:

Superego

In Freudian psychoanalysis, it represents the ethical component of the personality and provides the moral standards by which the ego operates.

Ego

In psychology, a component of Sigmund Freud's model of the psyche that represents the self, or the part of one's identity that mediates between the desires of the id and the constraints of the social environment.

Id

A part of the mind in Freudian psychoanalysis that is responsible for instinctual desires and drives.

Libido

The energy of the sexual drive as a component of the life instinct.