The allele for a cleft chin is dominant in humans what are the possible result for a cross between parents that have genotype cc and cc

Heterozygous Cc (50%) or homozygous cc (50%)

Explanation:

An individual with heterozygous Cc genotype would have the cleft chin phenotype, since the allele is dominant. An individual with homozygous cc genotype would not have the phenotype, since they don't have a copy of the cleft chin allele.

The punnet square of the cross between Cc and cc parents is attached. 1:2 genotypes are Cc, and 1:2 genotypes are cc.

Therefore, there is a 1:2 chance the individual will have a cleft chin

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.