Chordata
Chordates have a number of characteristics in common, which for most are only present during embryonic development.
The subphylum Cephalochordata has some characteristics of vertebrates and invertebrates. They have a closed circulatory system and no heart. They have a strong body wall like a vertebrate, and a caudal fin. It has gills, a mouth, and a notochord. The lancelet notochord, unlike the vertebrate spine, extends into the head. The Cephalochordates don't have bones, and grow up to about five centimetres long.
The subphylum Urochordata has gill slits for feeding. When an adult, their nervous system reduces to the dorsal ganglion. But during their larval stage, they have a notochord, dorsal nerve tube, and a tail.
- Notochord is found in all chordate embryos.
- A hollow dorsal nerve cord.
- Pharyngeal slits.
- Postanal tail.
The subphylum Cephalochordata has some characteristics of vertebrates and invertebrates. They have a closed circulatory system and no heart. They have a strong body wall like a vertebrate, and a caudal fin. It has gills, a mouth, and a notochord. The lancelet notochord, unlike the vertebrate spine, extends into the head. The Cephalochordates don't have bones, and grow up to about five centimetres long.
The subphylum Urochordata has gill slits for feeding. When an adult, their nervous system reduces to the dorsal ganglion. But during their larval stage, they have a notochord, dorsal nerve tube, and a tail.