The brain is composed of millions of nerve cells that relay messages to and from the body. Every sensation the body feels is sent to the brain for interpretation, and every muscle that moves is commanded to do so by the brain. When the glands secrete hormones or the kidneys filter blood, they do so under orders from the brain. The skull carries the brain within a sturdy case of bone and joins with the vertebral column, forming a flexible channel through which the spinal cord can descend.
The Facial Bones of the Skull
The facial area of the skull is composed of five major bones. The zygomatic bone forms the "cheekbone." The mandible is the lower jaw. The frontal bone forms the forehead. The maxilla forms the upper jaw and borders of the nose. Together these bones provide structure and shape to the face. A number of smaller bones, such as the vomer and palatine bones, play supporting roles in the inner architecture of the skull.
The Cranial Bones of the Skull
The cranial region houses the brain. It shares the frontal bone with the facial region, and includes the temporal, sphenoid, parietal and occipital bones, which form the top, sides, rear and bottom of the cranium. The occipital bone, located in the floor of the cranium, has a large opening called the foramen magnum, through which the spinal cord descends from the brain.
The Cerebrum
The lobes of the brain are called the frontal temporal, parietal and occipital lobes. Each lobe has its own specific role in mental processing. Some areas are associated with sensory perception, others with memory, speech or movement.
The Cerebellum
The cerebellum resembles a smaller version of the cerebrum, with a furrowed surface and a division into two hemispheres. Harvard University states that this part of the brain is associated with balance, movement and posture and is considered a less evolutionarily advanced structure than the cerebrum. Animals such as reptiles, which do not have a neocortex, have a cerebrum.
The Limbic System
Deep within the cerebrum lies another primitive brain structure called the limbic system. The limbic system contains areas called the thalamus, hypothalamus, hippocampus and amygdala, which are related to sensation, emotion, memory and fear, according to Serendip.
The Brain Stem
The brain stem is located below the limbic system, and is the point beyond which the brain becomes the spinal cord. The structures of the brain stem include the midbrain, pons and medulla oblongata, which Harvard University states are associated with breathing, sleeping and heart rate.
