15. Answer briefly III

Outline the flow charts of Phylum Chordata.

 

a. The phylum  are characterised by the presence of notochord, dorsal nerve cord and paired gill pouches.

 

b. Phylum chordata is divided into two groups -  and .

 

c. The phylum Prochordata is classified into subphylum , and subphylum .

 

d. The phylum  is characterized by the presence of vertebral column. They are grouped into  classes.

 

e. The class  are jawless vertebrates. Examples of the class include  and Hagfish.

 

f. The class  are poikilothermic and aquatic vertebrates with jaws.

 

g. The class  are the first four legged vertebrates with dual adaptation to live in both land and water.

 

h. The class  are vertebrates that are fully adapted to live on land.

 

i. The class  are homeothermic animals that has several adaptations to fly, has a spindle shaped body, and the forelimbs are modified into wings for flight.

 

j. The class  are warm blooded animals, where placenta is the unique characteristic features.