He cell membrane forms a protective barrier between the external and internal environments. it is referred to as because it allows some substances to cross more easily than others and blocks other substances from crossing into the cell.

The punnett square predicts the ratio of genotypes in the offspring, based on the genotypes of the parents. in this cross, tallness (h) is dominant to shortness (h). based on the punnett square, what is the phenotype of the offspring? hh hh tall short