In guinea pigs, rough coat (R) is dominant over smooth coat (r). Predict the genotypes and phenotypes of the offspring and give the genotypic and phenotypic ratios is a homozygous dominant guinea pig is crossed with a heterozygous guinea pig. 3. ... In humans, brown eyes (B) are dominant over blue (b).
        
             
        
        
        
The answer is Law of Dominance 
 
        
             
        
        
        
Answer:
D
Explanation:
the production of gametes
 
        
             
        
        
        
Answer:
The chance that their <u>child will not be able to roll his tongue will be zero</u>. 
The chances to have a child with tongue rolling ability is 100%.
Explanation:
In complete dominance, a dominant gene completely manifests over a recessive gene. If tongue rolling is a dominant trait, this means that the gene that expresses this trait is dominant over the recessive one that does not allow the person to roll the tongue.   
If the gene for tongue rolling is called T, then a person that is homozygous dominant for this trait will have the following genotype: TT. If the person is heterozygous for this trait, the genotype will be Tt. And if a person is homozygous recessive for the trait, this person´s genotype will be tt. 
When two homozygous dominant individuals mate, their chances to have a child with tongue rolling ability is 100%. 
This is:    
Parental)         TT   x   TT
Gametes)     T   T       T   T
Punnet Square)                  T                 T
                                 T        TT             TT
                                 T        TT             TT
F1)  Genotype: 100% TT, or 4/4 TT
       Phenotype: 100% Tongue rolling capable.