1. | the typhlosole greatly increases the effective absorption area of the digested food in the intestine |
2. | the S-shaped setae embedded in the integument are the defensive weapons used against the enemies |
3. | it has a long dorsal tubular heart |
4. | fertilization of eggs occurs inside the body |
If a live earthworm is pricked with a needle on its outer surface without damaging its gut, the fluid that comes out is:
1. excretory fluid
2. coelomic fluid
3. haemolymph
4. slimy mucus