The Ability to Roll the Edges of the Tongue Upward

question 12

Multiple Choice

The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability. The standard assumption is that tongue-rolling is a dominant allele at a single gene locus. Which of the following would cast doubt on this assumption?

• A) A teacher reports that after testing her class on the ability to roll their tongue, with very little effort the non-tongue-rollers can learn to also roll their tongues.
• B) A student who can roll his tongue has a mother and father, both of whom cannot.
• C) A student who cannot roll his tongue has a mother and father, both of whom can.
• D) Two of the above are situations that would cast doubt on this assumption.

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Definitions:

Sentinel Event

An unexpected occurrence involving death or serious physical or psychological injury, or the risk thereof, which necessitates immediate investigation and response.

Suicidal Tendencies

Patterns of thoughts or behaviors that indicate a higher risk of attempting suicide, often seen in individuals with a history of suicidal thoughts or attempts.

Shame

A painful feeling arising from the consciousness of something dishonorable, improper, or ridiculous done by oneself or another.

Self-imposed Isolation

The voluntary act of withdrawing oneself from social interactions and activities, often due to emotional distress or preference.