Cerebrum- the largest portion of the brain; is associated with higher mental functions, and sensory/motor functions, consists of 2 hemispheres and 4 lobes (frontal, temporal, parietal, and occipital), corpus callosum connects the two hemispheres, the cerebral cortex contains 75% of the neuron cell bodies in the nervous system and is composed of gray mater, white matter is made up of myelinated nerve fibers