Response To Environment/Movement

wasp
pill bug
grasshopper

Response
Most arthropods have well-developed nervous systems. They use a pair of ganglia located in the head and two long nerves near the esophagus that connect to the brain. From the brain a nerve cord with several more gangila, is connected and runs along the ventral part of the body. The ganglia serve as the main controls which coordinate the movements. Each major part of the arthropod are controled by several ganglia.

Arthropods also use sense organs such as statocysts ,chemical receptors. Arthropods also have many other sophisticated sense organs like compound eyes that can detect things our eyes cant.

Crustaceans and insects also sense things using their taste receptors and sensory hairs. Taste receptors are located in the mouth and in other strange places like their antenae and legs. Many insects have eardrums to detect movement of preditors or prey.

Movement
Arthropods use a muscle system that is controled by their nervous system for movement. When the muscles contract it generates a force which is then transfered to the exoskeleton. At each body joint there are muscles that are functionized to either extend or contract. When the arthropods use these muscles to pull against their exoskeleton it allows them to beat their wings against the air or push of the ground and other movements.
Most arthropods are motile only a few like the barnacles are sensile.