The General characteristics of phylum Chordata are as follows :
1. Presence of Notochord : It is stiff, flexible and solid rod like structure which helps in
supporting the internal body . It is situated between the alimentary canal and
nerve chord. It may be present in the embryonic stage only or throughout the
life. Later on in an adult it is replaced by vertebral column or
backbone.
2. Presence of Nerve chord
: It is hollow , tubular
nerve tissue. It is situated dorsally above the nerve chord. It is later on
replaced into brain and spinal chord.
3. Presence of Gill slit : It is paired lateral gill opening situated in
both side of pharynx. It is respiratory opening that take part in the exchange
of gases.
4. They have closed
circulatory system with RBC.
5. Presence of post anal
tail.
6. Presence of ventrally
situated heart.
7. They are triploblastic,
bilaterally symmetrical and coelomate.
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