Question

Identify the phylum to which an organism belonging to the following features belong:

1. They are mostly found in marine and freshwater. Very few are terrestrial and found in moist soil.

2. They exhibit organ system level of organization.

3. Their body has a cavity.

4. The body is divided into head, visceral mass, muscular foot and mantle.

5. The head comprises of tentacles and compound eyes.

6. The body is covered by a calcareous shell.

7. The muscular foot helps in locomotion.

8. They have a well-developed digestive system, the radula is the rasping organ for feeding.

9. They respire through the general body surface, gills or pulmonary sac.

10. The blood circulates through the open circulatory system.

11. They have a pair of metanephridia that helps in excretion.

12. The nervous system consists of number of paired ganglia and nerves.

13. The tentacles, eyes, osphradium, and statocysts act as the sensory organs.

14. The sexes are separate in most of the molluscs but some species are hermaphrodites. Fertilisation may be external or internal.

15. They are generally oviparous with indirect development.

Answer 1

The organisms belonging to phylum Mollusca exhibit the following characteristics:

1. They are mostly found in marine and freshwater. Very few are terrestrial and found in moist soil.

2. They exhibit organ system level of organization.

3. Their body has a cavity.

4. The body is divided into head, visceral mass, muscular foot and mantle.

5. The head comprises of tentacles and compound eyes.

6. The body is covered by a calcareous shell.

7. The muscular foot helps in locomotion.

8. They have a well-developed digestive system, the radula is the rasping organ for feeding.

9. They respire through the general body surface, gills or pulmonary sac.

10. The blood circulates through the open circulatory system.

11. They have a pair of metanephridia that helps in excretion.

12. The nervous system consists of number of paired ganglia and nerves.

13. The tentacles, eyes, osphradium, and statocysts act as the sensory organs.

14. The sexes are separate in most of the molluscs but some species are hermaphrodites. Fertilisation may be external or internal.

15. They are generally oviparous with indirect development.