1. | Arthropods | 2. | Hemichordates |
3. | Most molluscs | 4. | Annelids |
I: | They are exclusively marine. |
II: | They have cellular level of organisation. |
III: | They have a water vascular system with tube feet. |
IV: | Digestion is intracellular. |
V: | Fertilisation is external and development is direct. |
Column I | Column II | ||
A | Branchiostoma | P | Notochord persisting in adult |
B | Ascidia | Q | Notochord present only in larval tail |
C | Pristis | R | Cartilaginous endoskeleton |
D | Catla | S | Bone endoskeleton |
A | B | C | D | |
1. | P | Q | R | S |
2. | P | Q | S | R |
3. | Q | P | R | S |
4. | Q | P | S | R |
I: | are marine but migrate for spawning to fresh water. |
II: | die within a few days of spawning. |
Column I | Column II | ||
A | Limulus | P | Gregarious pest |
B | Locusta | Q | Living fossil |
C | Ancylostoma | R | Filaria worm |
D | Wuchereria | S | Hookworm |
A | B | C | D | |
1. | Q | P | S | R |
2. | P | Q | S | R |
3. | P | Q | R | S |
4. | Q | P | R | S |