Two Species Have Homologous Structures

question 1

Multiple Choice

Two species have homologous structures. What can we infer?

• A) The structures are identical.
• B) The structures have the same function.
• C) The species have very different ancestors.
• D) The species are related by a common ancestry.
• E) The structures have the same function and they are identical.

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Definitions:

Epidermis

The external layer of skin that acts as a waterproof barrier and determines our skin color.

Abducens

Refers to the abducens nerve (cranial nerve VI) that controls the lateral rectus muscle of the eye, responsible for abducting or moving the eye laterally.

Oculomotor

Pertaining to the third cranial nerve, which controls most of the eye's movements, the constriction of the pupil, and maintenance of eyelid elevation.

Trochlear

Refers to the fourth cranial nerve that controls the superior oblique muscle of the eye, aiding in rotational movement.