Shrimp belongs to crustacea of Arthropoda in morphological classification. Crustaceans include many species, such as plankton, ostracods and copepods, as well as benthic and fixed species, such as barnacles, turtle feet, shrimps and blue crabs. Its body can be divided into three sections: head, chest and abdomen. It has a chitin exoskeleton, that is, the breastplate of the head, with joint appendages and a mixed body cavity. This is an open circulatory system. Crustacean shells are the result of hardening of the body wall. The head and breastplate of shrimp do not grow with the growth of the body, so every once in a while, shrimp will shed its skin. Before molting, a new shell forms under the old shell, and the shrimp stops eating. When molting, in addition to molting the old shell, the inner epidermis of the intestine is also molted together. Because this layer is also developed from the ectoderm and cannot grow with the body. After shedding the old skin, the new shell gradually hardened, and the shrimp resumed feeding and began to grow. So the growth process of shrimp is also a molting process.
Shrimp shells can be used to extract chitin and can be used as fixative for scientists to study.
The blood of shrimp is transparent, because it does not contain iron, so the blood of shrimp is not red like the blood of some higher animals, but colorless. The red color of cooked shrimp is due to the change of pigment, not the rupture of blood vessel wall.
Shrimp is a swimming species, with a developed abdomen, a streamlined body shape and a tail fan. The last knuckle of the fifth pair of feet has become an oar adapted to swimming life.