Central nervous system: consists of brain and spinal cord. They both have different functions but they work together to make an intergraded system. they receive info about information about the environment from the senses. uses this information to send out messages to muscles and glands thereby creating behaviours an controlling movements. Neurons: basic functions and structure of neurons. Neurons are the basic unit, there are thousands of different neurons. They carry messages between neurons and they organize and intergrade information received. (billions: motor neurons: take the message from the central nervous system and carry them via nerves to muscles and glands. (millions) come in a variety of shapes and sizes. They share more or less the same basic structure. cell body: soma (middle) y y in the soma we find the dna function: to manufacture what the neuron needs to survive and grow.