Question: 163 Radial symmetry is NOT found in adults of phylum \_\_\_\_ .
(1) Coelenterata
(2) Echinodermata
(3) Ctenophora
(4) Hemichordata
Answer: Option (4)
Explanation:
Radial symmetry is a condition in which the body can be divided into similar halves by many vertical planes passing through the central axis.
Adults of phylum Coelenterata show radial symmetry.
Adults of phylum Echinodermata also show radial symmetry, although their larvae are bilaterally symmetrical.
Members of phylum Ctenophora exhibit radial symmetry.
Phylum Hemichordata shows bilateral symmetry in adults, not radial symmetry.
Therefore, radial symmetry is not found in adults of phylum Hemichordata.