Question

List the various systems and characteristics of each major coelomate in the animal groups of Arthropoda (Insects, Crustaceans, and Spiders) List skin/skin structures, skeleton, movement/type, digestive, respiratory, excretory, circulatory, habitat, and mode of existence for each.

Answer 1

	Insects	Crustaceans
Skin/Skin Structure	Exoskeleton – It is basically the skin of the insects	They have hard skin which helps in protecting it
Skeleton	No interior skeleton but it has only exoskeleton which is hard outer layer made of chitin that protects and supports the body	It has an external skeleton called cuticle that is made up of chitin.
Movement Type	Most of the insects move with help of their wings. However they also have muscles in their legs that help to crawl and move.	There are appendages in the crustaceans which helps in the movement of the crustaceans
Digestive	It has a closed digestive system that has one long enclosed coiled tube called alimentary canal	It has a close digestive system that absorbs the food and nutrients.
Respiratory	They have system of tubes called trachea and air enters the respiratory systems of insects with help of spiracles.	Open respiratory system where the blood is pumped in the hemocoel and the blood diffuses back into the circulatory system
Excretory	Most of the insects have the Malphigian tubule system for excretion.	The excretion in crustaceans take place with help of antennal gland and maxillary gland
Circulatory	Open circulatory system	Open circulatory system
Habitat	They live in all sorts of environment	They live in all sorts of habitats