Answer:
A. dihybrid crosses
Explanation:
A dihybrid cross can be defined as a mating experiment between two lines/varieties/organisms that differ in two phenotypic traits. By using pea plants, Mendel performed dihybrid crosses in order to analyze the mode of inheritance of both phenotypic traits at the same time. From these mating experiments, Mendel observed that the inheritance factors (nowadays called genes) sorted independently from one another in the next generation, which is called the principle/law of Independent Assortment.
It is important to understand because it's the way all cells reproduce (except sperm and egg cells, they do meiosis), and our cells are the essential parts of our whole being.
Answer:
The characteristic features of the phylum Chordata are a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a tailgut.
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