All vertebrates have bilateral symmetry and a true coelom. At the base of the phylogenetic tree, neither sponges nor cnidarians
have a coelom. Sponges have an asymmetric body plan; cnidarians have radial symmetric plan. What advantages do the bilateral symmetry and the coelom give to animals?
Bilateral symmetry allows for directional motion. The coelom cushions organs allow freedom of motion.
Explanation:
Most animals are bilaterally symmetrical in nature with a line of symmetry dividing their body into two sides left and right sides along-with a “head” in top and “tail” in the bottom. Bilateral symmetry consisting an equal arrangement of symmetry about a vertical plane running from top to bottom.
The coelom is known as the main body cavity present in most animals. It is positioned inside the body to surrounds the digestive tract and other organs. In some animals, it is lined with mesothelium. In other animals, such as mollusks, it is undifferentiated. In animals, it helps to allow freedom of motion.
