| Assertion (A): | Frogs have a three-chambered heart. | 
| Reason (R): | All vertebrates have a three chambered heart. | 
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A) | 
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). | 
| 3. | (A) is True but (R) is False. | 
| 4. | (A) is False but (R) is True. | 
| 1. | Cnidarians are diploblastic, ctenophores are triploblastic. | 
| 2. | Cnidarians are bilaterally symmetrical, ctenophores are radially symmetrical. | 
| 3. | Cnidarians have a gastrovascular cavity, ctenophores do not. | 
| 4. | Cnidarians possess cnidocytes, while ctenophores do not. | 
| Phylum (List I) | Characteristic Feature (List II) | ||
| A. | Chordata | 1. | Spicules for support | 
| B. | Porifera | 2. | Notochord present at some stage | 
| C. | Echinodermata | 3. | Segmented body | 
| D. | Annelida | 4. | Radial symmetry and water vascular system | 
| Assertion (A): | Roundworms (phylum Nematoda) are pseudocoelomates. | 
| Reason (R): | Pseudocoelom provides protection for internal organs and facilitates movement of nutrients. | 
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). | 
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). | 
| 3. | (A) is True but (R) is False. | 
| 4. | (A) is False but (R) is True. | 
| 1. | Urochordates retain their notochord throughout their life, whereas Cephalochordates lose their notochord during the larval stage. | 
| 2. | Cephalochordates, such as lancelets, retain a notochord extending the full length of their body into adulthood, whereas Urochordates, like tunicates, only possess a notochord during their larval stage. | 
| 3. | Both Urochordates and Cephalochordates exhibit a complex nervous system comparable to that of higher vertebrates. | 
| 4. | Urochordates are primarily terrestrial, whereas Cephalochordates are exclusively aquatic. | 
| 1. | Osteichthyes possess a swim bladder which aids in buoyancy, whereas Chondrichthyes lack a swim bladder and must constantly swim to avoid sinking. | 
| 2. | Chondrichthyes have an operculum covering their gills, while Osteichthyes do not have any covering over their gill slits. | 
| 3. | Both Osteichthyes and Chondrichthyes have a skeleton made entirely of bone, making them rigid and durable in aquatic environments. | 
| 4. | Chondrichthyes exhibit external fertilization whereas Osteichthyes typically display internal fertilization mechanisms. | 
| I: | All annelids are hermaphrodites. | 
| II: | Bioluminescence is well-marked in cnidarians. | 
| 1. | All chordates possess a notochord at some stage of their life cycle. | 
| 2. | Chordates exclusively exhibit asexual reproduction. | 
| 3. | Chordates lack a dorsal hollow nerve cord. | 
| 4. | Chordates are exclusively aquatic organisms. | 
| Column I | Column II | ||
| A | Reptilia | P | Egg spawning on water surface | 
| B | Amphibia | Q | Presence of mammary glands | 
| C | Aves | R | Skin covered with scales or scutes | 
| D | Mammalia | S | Endothermic with feathers | 
| A | B | C | D | |
| 1. | R | P | Q | S | 
| 2. | Q | P | R | S | 
| 3. | R | P | S | Q | 
| 4. | S | P | Q | R | 
| Assertion (A): | Adult echinoderms exhibit radial symmetry. | 
| Reason (R): | Adult echinoderms are diploblastic. | 
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A) | 
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A) | 
| 3. | (A) is True but (R) is False | 
| 4. | (A) is False but (R) is True |