Final answer:
Schwann cells and oligodendrocytes are both types of glial cells that support and protect neurons. The cerebellum is not the largest part of the brain and is divided into four lobes.
Step-by-step explanation:
Schwann cells and oligodendrocytes are both types of glial cells, which are responsible for supporting and protecting neurons in the central nervous system. Schwann cells are found in the peripheral nervous system and wrap around axons to form myelin sheaths, which insulates and speeds up the conduction of electrical impulses. Oligodendrocytes, on the other hand, are found in the central nervous system and perform a similar function by forming myelin sheaths around axons.
Regarding the second question, the cerebellum does not make up most of the brain; it is located at the back of the brain below the cerebrum and is responsible for coordinating movement, balance, and posture. The cerebrum, which is the largest part of the brain, is divided into two hemispheres and four lobes: frontal, parietal, temporal, and occipital.