11.
A neuromuscular junction is a "connection" between the terminal of a motor
neuron and a muscular fiber. Comparison: The neuromuscular junction has an
organization identical to a synapse. However, the bulb is larger and protrudes into
the surface of the muscle fiber. The postsynaptic membrane is also larger and
12.
The major divisions of the human nervous system are the central nervous system
(CNS), the peripheral nervous system (PNS), and the autonomic nervous system
(ANS). The CNS is made up of the brain and the spinal cord. (para 11-8)
13.
The three major subdivisions of the human brain are the brainstem, the
cerebellum, and the cerebrum. The brainstem is that part of the brain remaining
after removal of the cerebrum and cerebellum. It is the basal portion. Together
with the spinal cord, it is known as the neuraxis. (para 11-9a)
14.
The cerebellum is a spherical mass of nervous tissue attached to and covering the
hindbrainstem. Its three major parts are the vermis and right and left cerebellar
hemispheres. In addition, the cerebellum has three pairs of stem-like connecting
parts called peduncles. The outer cortex is composed of gray matter, which is the
cell bodies of neurons. More central is the white matter, which is the myelinated
processes of neurons. The cerebellum is the primary coordinator/ integrator of
15.
The cerebrum consists of two very much enlarged hemispheres connected to each
other by a special structure called the corpus callosum. Each cerebral hemisphere
is connected to the brainstem by a cerebral peduncle. The surface of each
cerebral hemisphere is subdivided into areas known as lobes. The names of the
four lobes are frontal, parietal, occipital, and temporal. (para 11-9c)
16.
The space separating the two cerebral hemispheres is called the longitudinal
fissure. The shallow grooves in the surface of the cerebrum are called sulci. The
17.
The gray outer layer of each hemisphere is the cerebral cortex. Deeper within the
cerebral hemispheres, the tissue is colored white. The "gray matter" represents
the cell bodies of the neurons. The "white matter" represents the axons.
18.
Groups of related functions are associated with specific areas of the cerebral
cortex. For example, centers of speech and hearing are located along the lateral
sulcus. Vision is centered in the occipital lobe. Sensory and motor functions are
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