Review Exercise 5.4
Metencephalon－The region of the brain stem between the mesencephalon and the myelencephalon；one of the two divisions of the hindbrain (the other is the myelencephalon).
Myelencephalon－The most posterior region of the brain ; the area of the brain stem between the metencephalon and the spinal cord ; one of the two divisions of the hindbrain (the other is the metencephalon ) .
Nerves－Structures of the PNS that are composed largely of axons ; their function is to conduct action potentials from one part of the PNS to another .
Nuclei－Structures of the CNS that are composed largely of neural cell bodies ; their function is the local analysisf neural signals ( singular : nucleus ) .
Olfactory nerves－The first pair of cranial nerves ; they carry sensory signals from the olfactory bulbs to the brain .
Optic nerves－The second pair of cranial nerves ; they carry sensory signals from the visual receptors of the eyes to the brain .
Pia mater－The innermost and most delicate of the three meninges ; it adheres to the surface of the CNS .
Subarachnoid space－The space between the arachnoid membrane and the pia mater ; it contains cerebrospinal fluid , the weblike processes of the arachnoid layer , and many blood vessels .
Telencephalon－The cerebral hemispheres ; one of the two divisions of the forebrain (the other is the diencephalon) .
Third ventricle－The cerebral ventricle of the diencephalon ; it is a vertical sheet-shaped chamber that lies along the midline .
Tracts－Structures of the CNS that are composed largely of axons ; their function is to conduct action potentials from one part of the CNS to another .
Trigeminal nerves－The fifth pair of cranial nerves , each of which has three major branches ; they conduct motor signals from the brain to the muscles involved in chewing , and sensory signals from the same muscles and from other parts of the face to the brain .
Vagus nerves－The tenth and longest pair of cranial nerves ; they conduct signals to and from the organs of the gut (e.g., to and from the heart , liver , and stomach) .