Can YOU curl your tongue up on the sides?

Question

Scientists Debunk Familiar Tongue-Rolling Lore | HuffPost Impact

We are pretending that tongue-curling in humans is a dominant genetic trait.

Suppose a man who is Tt for tongue-curling marries a woman who is also Tt for this trait. What are the possible genotypes and phenotypes of their children, and the percent chance for each?

Genotype Phenotype (curl or no curl) Percent Chance (number only)
TT
Tt
tt
Blank 1:
Blank 2:
Blank 3:
Blank 4:
Blank 5:
Blank 6:

Answer 1

To determine the possible genotypes and phenotypes of the children from a man who is Tt (heterozygous for tongue-curling) and a woman who is also Tt, we can use a Punnett square.

The genotypes of the parents:

• Father: Tt
• Mother: Tt

Using a Punnett square for the Tt x Tt cross:

      T    |    t
------------------
T |   TT   |   Tt
------------------
t |   Tt   |   tt

From this Punnett square, we can see the possible genotypes for their children:

1. TT - Homozygous dominant
2. Tt - Heterozygous
3. tt - Homozygous recessive

Now, let's summarize the phenotypes and the percent chance for each genotype:

• TT: Phenotype (curl): 1 way to have TT
• Tt: Phenotype (curl): 2 ways to have Tt (Tt or tT)
• tt: Phenotype (no curl): 1 way to have tt

Now calculating the probabilities:

• TT: 1 out of 4 = 25%
• Tt: 2 out of 4 = 50%
• tt: 1 out of 4 = 25%

So, the completed table would be:

| Genotype | Phenotype (curl or no curl) | Percent Chance | |----------|---------------------------|----------------| | TT | curl | 25 | | Tt | curl | 50 | | tt | no curl | 25 |

Thus, filling in the blanks:

Blank 1: TT
Blank 2: curl
Blank 3: 25
Blank 4: Tt
Blank 5: curl
Blank 6: 50
Blank 7: tt
Blank 8: no curl
Blank 9: 25