Question

1. can you curl your tongue? tongue - curling in humans (t) is a dominant genetic trait. derek can curl his tongue but his wife, ashley, cannot. all nine of their children can curl their tongues. complete the punnett square based on the genotypes they most likely have. derek ashley phenotype probability (%) tongue - curling: cannot curl tongue:

Explanation:

Step1: Determine the genotypes

• Since tongue - curling (T) is dominant, Ashley (who cannot curl her tongue) has the genotype \( tt \).
• All of their children can curl their tongues. If Derek had a heterozygous genotype \( Tt \), there would be a \( 50\%\) chance of children not being able to curl their tongues (\( Tt\times tt \) gives \( Tt:tt = 1:1 \)). But since all children can curl their tongues, Derek must have the homozygous dominant genotype \( TT \).

Step2: Create the Punnett square

• Derek (\( TT \)) can only contribute \( T \) gametes.
• Ashley (\( tt \)) can only contribute \( t \) gametes.
• The Punnett square will have \( Tt \) in all four boxes (\( T\times t\) and \( T\times t\) for Derek's \( T \) and Ashley's \( t \) gametes).

Step3: Calculate probabilities

• For tongue - curling (\( Tt \)): Since all offspring have the \( Tt \) genotype (which shows the dominant phenotype), the probability is \( 100\%\).
• For not being able to curl the tongue: There are no \( tt \) genotypes (as all are \( Tt \)), so the probability is \( 0\%\).

Answer:

Tongue - curling: \( 100\%\)
Cannot Curl Tongue: \( 0\%\)