Humans Are the Only Primates Who Lack a Sectorial Complex

question 22

Multiple Choice

Humans are the only primates who lack a sectorial complex on the premolar.This is an example of

• A)a primitive trait, because it is present in multiple species of a group.
• B)a primitive trait, because it is present in only one or few species of a group.
• C)a derived trait, because it is present in multiple species of a group.
• D)a derived trait, because it is present in only one or few species of a group.

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Definitions:

Venography

A diagnostic procedure that involves imaging the veins by injecting them with a contrast dye to make them visible on X-rays.

Cholecystography

A diagnostic imaging procedure used to visualize the gallbladder, typically involving the use of a radiopaque contrast medium.

Tomography

Imaging by sections or sectioning, using any kind of penetrating wave, to create a three-dimensional image of the inside of an object.

Myelogram

A radiographic examination of the spinal canal and nerve roots by injecting contrast dye to detect abnormalities or injuries.