(a) The brain and the rest of the nervous system are composed of many different types of cells, but the primary functional unit is a cell called the neuron.
(b) The small gap between the consecutive neurons is called a synapse (or synaptic gap, or synaptic cleft).
(c) The cerebellum - part of the brain coordinates voluntary movements such as posture, balance, coordination and speech, resulting in smooth and balanced muscular activity.