Two tongue-rollers have 12 children. 8 of their children can roll their tongues and 4 cannot. make an argument about the genotype of each of the parents and use a punnett square to explain your reasoning.

Let  the  dominant gene  for  tongue rolling  be  R  while  the  receive gene  be r. Therefore the  genotype  of  the  parent  is  heterogeneous  that  Rr  x Rr  since   they are  having  children  who  are  not  able  to  roll  the  tongue.The  punnet   square  is  as  follows.