Jamie is still mad and he doesn't understand Vicky's explanation. He says "You aren't even speaking English! What are heterozygous parents? What's a recessive allele?

Explanation:

The term Heterozygous and the recessive alleles are used in the Genetics to refer to the allele conditions present in an organism. The trait of an organism is controlled by the genes which are present in its alternative form on the chromatids at a position called locus.

Recessive alleles

A trait is expressed when each parent contributes one allele and when these two alleles come in complementary position express its effect. The alleles which express its highest effect on a trait is called dominant allele and the other allele which is not able to show its effect or is suppressed is called the recessive allele.

Heterozygous parents

In such condition, when an organism has one dominant and one recessive allele is known as a heterozygous organism and if the allele pair has either both dominant or both recessive alleles are homozygous organisms.

"a.) well–developed vascular system."