Which structure is the largest portion of the brain and contains the four lobes?

• A. Cerebellum
• B. Cerebrum
• C. Brainstem
• D. Diencephalon

Answer: (B)

The cerebrum is the largest portion of the brain and contains the four lobes. It consists of two hemispheres connected by the corpus callosum and houses the cerebral cortex, where much of higher thinking, sensation, voluntary movement, language, and memory occur. The four lobes—frontal, parietal, temporal, and occipital—each have distinct roles: the frontal lobe plans and executes movements and supports reasoning and speech; the parietal lobe processes touch and spatial information; the temporal lobe handles hearing and memory; the occipital lobe is mainly responsible for vision. Behind and beneath the cerebrum lies the cerebellum, which coordinates movement and balance, while the brainstem governs vital functions like breathing and heart rate, and the diencephalon (between the cerebrum and brainstem) contains the thalamus and hypothalamus involved in relay and autonomic regulation. Because of its size and expansive cortical surface, the cerebrum is the largest structure and houses the four lobes.