Question 2
Answer the following: (i) What is the function of nephridia? (ii) How many types of nephridia are found in earthworm based on their location?
(i) Nephridia are segmentally arranged excretory organs present in earthworms.
(ii) On the basis of their location, three types of nephridia are found in earthworms. They are:
(a) Septal nephridia: These are present on both sides of the inter-segmental septa behind the 15th segment and they open into the intestine.
(b) Integumentary nephridia: These lie attached to the body wall from the third segment to the last segment, which opens on the body surface.
(c) Pharyngeal nephridia: These are present as three paired tufts in fourth, fifth, and sixth segments.
