Which of the following is the smallest taxonomic group of animals having a cranium,vertebral column,ventral heart,pulmonary respiration,and two pairs of limbs?

The notochord is restricted to the tail region only in:

Which of the following statements are true for the phylum $Chordata$?
$(a)$ In $Urochordata$,the notochord extends from head to tail and is present throughout their life.
$(b)$ In $Vertebrata$,the notochord is present during the embryonic period only.
$(c)$ The central nervous system is dorsal and hollow.
$(d)$ $Chordata$ is divided into $3$ subphyla: $Hemichordata$,$Tunicata$,and $Cephalochordata$.

$Branchiostoma$ is an example of

Write the general characters of phylum Chordata.

Development of the mouth later than the anus during embryonic development is a condition called: