What is trochophore?
It is the free-swimming larva of annelids and molluscs.
What are organs of locomotion in Polychaeta and Oligochaeta?
The organs of locomotion of class Polychaeta are parapodia while organs of locomotion in class Oligochaeta are setae.
Give examples of class Polychaeta.
Nereis and Chaetopterus are important examples of Polychaeta.
Name various classes of Phylum Annelida.
Polychaeta, Oligochaeta, and Hirudinea are classes of Phylum Annelida.
Give examples of class Oligochaeta.
Lumbricus terrestris, and Pheretima posthuma are examples of class Oligochaeta.
What are annuli?
Each segment in Hirudinea has additional circular rings or markings called annuli.
Why earthworm is termed as natural plough?
Earthworm is perhaps most active segmented worm in churning the soil, therefore it is commonly termed as natural plough