Which feature is common to Amphioxus, frog, sea horse and crocodile?
A. Pharyngeal gill slits, at least in the developmental stages
B. A three-chambered heart
C. Dorsal solid nerve chord
D. Skeleton formed of cartilage and bones
Answer:A
Which feature is common to Amphioxus, frog, sea horse and crocodile?
A. Pharyngeal gill slits, at least in the developmental stages B. A three-chambered heart C. Dorsal solid nerve chord D. Skeleton formed of cartilage and bones