One example of animals having a single opening to the outside that serves both as mouth as well as the anus is:
1. Octopus
2. Asterias
3. Ascidia
4. Fasciola
The figure shows four animals (a), (b), (c) and (d). Select the correct answer with respect to a common characteristic of two of these animals:
| (a) | (b) | ||
| (c) | (d) |
1. (c) and (d) have a true coelom
2. (a) and (d) respire mainly through body wall
3. (b) and (c) show radial symmetry
4. (a) and (b) have cnidoblasts for self-defence
| List-I | List-II | ||
| (A) | Contractile vacuole | (I) | Asterias |
| (B) | Water vascular system | (II) | Amoeba |
| (C) | Canal system | (III) | Spongilla |
| (D) | Flame cells | (IV) | Taenia |
| Options: | (A) | (B) | (C) | (D) |
| 1. | (IV) | (II) | (I) | (III) |
| 2. | (I) | (III) | (II) | (IV) |
| 3. | (III) | (II) | (I) | (IV) |
| 4. | (II) | (I) | (III) | (IV) |
Read the following statements.
| (a) | Metagenesis is observed in Helminths. |
| (b) | Echinoderms are triploblastic and coelomate animals. |
| (c) | Round worms have organ-system level of body organization. |
| (d) | Comb plates present in ctenophores help in digestion. |
| (e) | Water vascular system is characteristic of Echinoderms. |
Choose the correct answer from the options given below:
1. (a), (d) and (e) are correct
2. (b), (c) and (e) are correct
3. (c), (d) and (e) are correct
4. (a), (b) and (c) are correct
Biradial symmetry and lack of cnidoblasts are the characteristics of:
1. Starfish and sea anemone
2. Ctenoplana and Beroe
3. Aurelia and Paramecium
4. Hydra and starfish
Which one of the following kinds of animals are triploblastic?
1. Flatworms
2. Sponges
3. Ctenophores
4. Corals
| List-I | List-II | ||
| A. | Pleurobrachia | I. | Mollusca |
| B. | Radula | II. | Ctenophora |
| C. | Stomochord | III. | Osteichthyes |
| D. | Air bladder | IV. | Hemichordata |
| A. | Cockroach | B. | Leech |
| C. | Housefly | D. | Tapeworm |
| E. | Earthworm | ||
| 1. | A, B and D only | 2. | C and D only |
| 3. | B, D and E only | 4. | A, C and E only |
| List-I | List-II | ||
| A. | Taenia | I. | Nephridia |
| B. | Paramoecium | II. | Contractile vacuole |
| C. | Periplaneta | III. | Flame cells |
| D. | Pheretima | IV. | Urecose gland |
| Options: | A | B | C | D |
| 1. | II | I | IV | III |
| 2. | I | II | III | IV |
| 3. | I | II | IV | III |
| 4. | III | II | IV | I |
| A: | Platyhelminthes are triploblastic, pseudocoelomate and bilaterally symmetrical organisms. |
| B: | Ctenophores reproduce only sexually and fertilization is external. |
| C: | In tapeworm, fertilization is internal but sexes are not separate. |
| D: | Ctenophores are exclusively marine, diploblastic and bioluminescent organisms. |
| E: | In sponges, fertilization is external and development is direct. |
| 1. | (A), (C) and (D) only | 2. | (B), (C) and (D) only |
| 3. | (A) and (E) only | 4. | (B) and (D) only |