Answer
Swimmerets are paired abdominal appendages on the bodies of some crustaceans ( shrimps, lobsters) used for locomotion and in reproduction--in males for copulation, and in females for carrying eggs and transporting the young.
Maxillipeds: Maxillipeds are the first three pairs of Crustacean thoracic appendages just behind the mouthparts; They are modified for feeding/food handling.
Chelipeds; These are the first pair of walking legs that are enlarged. Their large strong claws enable them to function in defense.
Nauplius; These are free-swimming larval stages of some Crustaceans such as costracods copepods and barnacles.
Work Step by Step
There are many modifications of Crustacean appendages: Some modifications are for feeding, some for defence, some for swimming, some for copulation ( gonopods) some for attachment of eggs, and some for transporting the young.
