*Unoxygenated blood is driven forward via ventral aorta, passes through a series of branchial arteries in the gills or lungs (as the case may be), where gas exchange takes place. The oxygenated blood flows to the body, most of it returning to its origin via a dorsal aorta. *Red blood corpuscles contain haemoglobin. i) Bilateral symmetry – *Chordates are bilaterally symmetrical, which means there is a line of symmetry that divides their body into halves that are roughly mirror images of each other. *Bilateral symmetry is not unique to chordates. Other groups of animals, such as arthropods, segmented worms, and echinoderms (during the larval stage) exhibit bilateral
*Unoxygenated blood is driven forward via ventral aorta, passes through a series of branchial arteries in the gills or lungs (as the case may be), where gas exchange takes place. The oxygenated blood flows to the body, most of it returning to its origin via a dorsal aorta. *Red blood corpuscles contain haemoglobin. i) Bilateral symmetry – *Chordates are bilaterally symmetrical, which means there is a line of symmetry that divides their body into halves that are roughly mirror images of each other. *Bilateral symmetry is not unique to chordates. Other groups of animals, such as arthropods, segmented worms, and echinoderms (during the larval stage) exhibit bilateral