The group of cells bodies in the peripheral nervous system are known as ganglia. The axon pathways arising from these cell bodies are called nerves. Most ganglial cells are sensory neurons , which gather nerve information from the somatosensory system and motor neurons, which transfer processed information to muscles, glands, and internal organs in the body.
In vertebrates, there are three types of ganglia, namely; a dorsal root ganglia spinal ganglia , which contain the cell bodies of sensory nerves, b cranial nerve ganglia , which contain neurons of cranial nerves , and c autonomic ganglia , which consist of the cell bodies of autonomic nerves. Pseudoganglia is not actual ganglia made up of cell bodies, but only localized thickening of nerves that appear as cell bodies.
The cerebellum contains dentate nucleus, emboliform nucleus, globose nucleus, and fastigial nucleus. The basal nuclei of the front section of the brain are shown in figure 3.
Ganglia: Ganglia refer to the structures that contain a number of cell bodies of the peripheral nervous system. Nuclei: Nuclei refer to the structures that contain a number of cell bodies of the central nervous system. Nuclei: Nuclei occur in the gray matter of the brain. Ganglia: Dorsal root ganglia, autonomic ganglia, and cranial nerve ganglia are the examples of ganglia. Nuclei: Caudate, putamen, dentate, emboliform, pallidum, substantia nigra, and subthalamic nuclei are examples of nuclei.
Ganglia and nuclei are clusters of nerve cell bodies. Ganglia are cell bodies of the sensory neurons in the PNS. They are arranged in the both sides of the spinal cord. Nuclei are the clusters of cell bodies of the nerve cells in the CNS. The cell bodies of both motor neurons and the sensory neurons form nuclei. The main difference between ganglia and nuclei is the type of cell bodies present in each type of clusters.
Nerves in the PNS are typically divided into cranial and spinal nerves. There are twelve pairs of cranial nerves and thirty one pair of spinal nerves. Cranial nerves innervate parts of the head and connect directly to the brain especially to the brainstem. They are typically assigned Roman numerals from 1 to 12, although cranial nerve zero is sometimes included.
In addition, cranial nerves have descriptive names. Spinal nerves innervate much of the body, and connect through the spinal column to the spinal cord. They are given letter-number designations according to the vertebra through which they connect to the spinal column. The central nervous system consists of a central cavity surrounded by gray matter made of neuronal cell bodies and white matter made of myelinated axons.
The central nervous system CNS is comprised of white and gray matter. In the spinal cord and cerebrum gray matter is surrounded by white matter. However, in the cerebellum and cerebral hemispheres this is reversed with the grey matter surrounding underlying white matter. Gray matter is a major component of the CNS, it refers to un-myelinated neurons and other cells of the central nervous system such as glial cells and dendrites. It is present in the brain, brainstem and cerebellum, and present throughout the spinal cord.
The grey matter includes regions of the brain involved in muscle control, and sensory perception such as seeing and hearing, memory, emotions, speech, decision making, and self-control. Grey and White Matter : Micrograph showing grey matter, with the characteristic neuronal cell bodies right of image — darker pink , and white matter with its characteristic fine mesh work-like appearance left of image — lighter pink.
A second major component of the CNS is white matter. It is composed mainly of bundles of myelinated axons, with very few neuronal bodies. White matter connects the various grey matter regions of the nervous system to each other and carries nerve impulses between neurons. Myelin, the lipid that forms a thin layer, known as the myelin sheath, around the axons providing electrical insulation is white in color, giving rise to the name white matter.
Privacy Policy. In the central nervous system, a collection of neuron cell bodies is called a nucleus. In the peripheral nervous system, a collection of neuron cell bodies is called a ganglion plural: ganglia. The one exception to this rule that you may have encountered is the basal ganglia in the brain.
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