How many types of nephridia are found in earthworm based on their location?
Explanation Three types of nephridia can be found in earthworms. This categorization of nephridia is based on their location. Septal nephridia: Nephridia, which are present on the side of intersegmental septa behind the fifteenth segment, are known as septal nephridia that open into the intestine. Integumentary nephridia: These nephridia are present on the wall starting from the third segment to the last segment and open on the surface of the body. Pharyngeal nephridia: These nephridia are present in triple pairing tufts and found in the fourth, fifth, and sixth segments. These nephridia discharge excretory fluid into the gut. Final answer Three types of nephridia are present in the earthworm. Septal nephridia are present on the side of intersegmental septa, whereas integumentary nephridia are present on the wall of all the segments found between the third to last segment. The third type of nephridia is pharyngeal, which is present in the form of three paired tufts in the segments.
