Chordate vs Non-Chordate Features — NEET Biology

Correct answer: B — S1, S3 and S5

The question asks for correct statements regarding the classification and features of various animal phyla based on NCERT. S1: Correct. Coelenterates are described as "diploblastic" and "radially symmetrical animals" (NCERT page 38, section 4.1.3 and page 41, section 4.2.2). Platyhelminthes are described as "triploblastic animals" (NCERT page 39, section 4.1.3) and "bilaterally symmetrical" (NCERT page 42, section 4.2.4). S2: Incorrect. Aschelminthes are "pseudocoelomate animals" (NCERT page 39, section 4.1.4 and page 43, section 4.2.5). Platyhelminthes are "acoelomates" (NCERT page 39, section 4.1.4 and page 42, section 4.2.4). Therefore, stating both are acoelomate is false. S3: Correct. NCERT states, "Bioluminescence (the property of a living organism to emit light) is well-marked in ctenophores" and "The body bears eight external rows of ciliated comb plates, which help in locomotion" (NCERT page 42, section 4.2.3). S4: Incorrect. Annelids and Arthropods show metameric segmentation (NCERT page 39, section 4.1.5 and Table 4.2). However, Mollusca are described as having a body that "is unsegmented" (NCERT page 44, section 4.2.8 and Table 4.2). All three do exhibit organ-system level of organisation. S5: Correct. Echinoderms are described as "triploblastic and coelomate animals" (NCERT page 45, section 4.2.9). It also states, "The adult echinoderms are radially symmetrical but larvae are bilaterally symmetrical" (NCERT page 45, section 4.2.9). Therefore, statements S1, S3, and S5 are correct. The final answer is B.