A Patient Who Is Able to Smile While Laughing but Cannot

question 21

Multiple Choice

A patient who is able to smile while laughing but cannot smile on command likely has a:

• A)unilateral lesion of the facial nerve
• B)unilateral lesion of an upper motor neuron innervating the facial nerve
• C)bilateral lesion of the facial nerve
• D)bilateral lesion of the upper motor neurons innervating the facial nerve

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Definitions:

Down Syndrome

A genetic disorder caused by the presence of all or part of a third copy of chromosome 21, characterized by developmental delays and physical features such as a flat facial profile.

Genetic Disorders

Diseases or conditions that result from abnormalities in an individual's DNA, often inherited from one's parents.

Trisomy

Chromosome condition in which a diploid cell has one more chromosome than normal; designated as 2n + 1.

Extra Copy

In genetics, refers to an additional copy of a gene or chromosome segment, potentially leading to variations in traits or disease susceptibility.