What Is the First Event in the Development of the Face

question 22

Multiple Choice

What is the first event in the development of the face during the later part of the fourth week of prenatal development?

• A) Disintegration of the oropharyngeal membrane
• B) Paired mandibular processes fusion at the midline to form the mandibular arch
• C) Folding of the embryonic structure into a tubal one
• D) Thickening of the facial placodes

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Definitions:

Dorsal Rami

Branches of spinal nerves that innervate muscles and skin of the back.

Endorphins

Natural pain-relieving and happiness-inducing chemicals produced by the brain in response to stress or discomfort.

Neurotransmitters

Chemicals in the brain and body that transmit signals across neurons.

Vestibulocochlear

Pertaining to the vestibulocochlear nerve, which transmits sound and equilibrium (balance) information from the inner ear to the brain.