Cystic Fibrosis Is a Recessive Disorder

question 80

Multiple Choice

Cystic fibrosis is a recessive disorder.If a couple,each of whom is heterozygous for the CFTR mutation,have children,what is the probability that they will have a child with cystic fibrosis?  

• A)0%
• B)25%
• C)50%
• D)75%
• E)100%

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Definitions:

Mastication

Breaking down food by chewing it as a preparatory step for swallowing and digestion.

Buccinator

A muscle of the cheek, important in the action of chewing, blowing, and sucking.

Salivary Gland

Gland that produces and secretes saliva into the oral cavity. The three major pairs of salivary glands are the parotid, submandibular, and sublingual glands.

Facial Nerve

The seventh cranial nerve that controls the muscles of facial expression, taste sensation from the anterior two-thirds of the tongue, and supplies some glands.