33. Which of the following statements regarding the nervous system is FALSE? (A) Schwann cell is also a kind of nerve cell and found in the peripheral nervous system (PNS). (B) The functional unit of the nervous system is the neuron. (C) Sensory neurons convey signal from sensory receptors into the central nervous system (CNS). (D) Motor neurons convey signals from the CNS to effector cells. (E) PNS has ganglia, clusters of neuron cell bodies.