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Lateral Propriospinal Tract
Lateral propriospinal tract is a collection of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. Its fibers are largely myelinated. It is a component of the white lateral columns. Most prominent in the cervical and lumbar regions, it is located close to the spinal central gray. Shorter fibers are closer to, longer fibers further from the gray The tract is one of three propriospinal tracts in which most pathways intrinsic to the spinal cord are located. The others are the ventral propriospinal tract Ventral propriospinal tract is a collection of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. It is a component of the white anterior columns. The fibers are largely myelinated and r ... and the dorsal propriospinal tract. References External links * More information aBrainInfo Spinal cord tracts {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myelinated
Myelin Sheath ( ) is a lipid-rich material that in most vertebrates surrounds the axons of neurons to insulate them and increase the rate at which electrical impulses (called action potentials) pass along the axon. The myelinated axon can be likened to an electrical wire (the axon) with insulating material (myelin) around it. However, unlike the plastic covering on an electrical wire, myelin does not form a single long sheath over the entire length of the axon. Myelin ensheaths part of an axon known as an internodal segment, in multiple myelin layers of a tightly regulated internodal length. The ensheathed segments are separated at regular short unmyelinated intervals, called nodes of Ranvier. Each node of Ranvier is around one micrometre long. Nodes of Ranvier enable a much faster rate of conduction known as saltatory conduction where the action potential recharges at each node to jump over to the next node, and so on till it reaches the axon terminal. At the terminal the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Column
The lateral grey column (lateral column, lateral cornu, lateral horn of spinal cord, intermediolateral column) is one of the three grey columns of the spinal cord (which give the shape of a butterfly); the others being the anterior and posterior grey columns. The lateral grey column is primarily involved with activity in the sympathetic division of the autonomic motor system. It projects to the side as a triangular field in the thoracic and upper lumbar regions (specifically T1- L2) of the postero-lateral part of the anterior grey column. Background information Nervous system The nervous system is the system of neurons, or nerve cells that relay electrical signals through the brain and body. A nerve cell receives signals from other nerve cells through tree-branch-like extensions called dendrites and passes signals through a long extension called an axon (or nerve fiber). Synapses are places where one cell's axon passes information to another cell's dendrite by sending chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cervix
The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time of Hippocrates, over 2,000 years ago. The cervix is approximately 4 cm long with a diameter of approximately 3 cm and tends to be described as a cylindrical shape, although the front and back walls of the cervix are contiguous. The size of the cervix changes throughout a woman's life cycle. For example, women in the fertile years of their reproductive cycle tend to have larger cervixes than postmenopausal women; likewise, women who have produced offspring have a larger cervix than those who have not. In relation to the vagina, the part of the cervix that opens to the uterus is called the ''internal os'' and the opening of the cervix in the vagina is called the ''external os''. Between them is a conduit commonly called the cervic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lumbar
In tetrapod anatomy, lumbar is an adjective that means of or pertaining to the abdominal segment of the torso, between the diaphragm (anatomy), diaphragm and the sacrum. Naming and location The lumbar region is sometimes referred to as the lower vertebral column, spine, or as an area of the back in its proximity. In human anatomy the five lumbar vertebrae (vertebrae in the lumbar region of the back) are the largest and strongest in the movable part of the spinal column, and can be distinguished by the absence of a foramen transversarium, foramen in the transverse process, and by the absence of facets on the sides of the body. In most mammals, the lumbar region of the spine curves outward. Description The actual spinal cord terminates between vertebrae one and two of this series, called L1 and L2. The central nervous system, nervous tissue that extends below this point are individual strands that collectively form the cauda equina. In between each lumbar vertebra a nerve root exi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the lower brainstem to the lumbar region of the vertebral column (backbone) of vertebrate animals. The center of the spinal cord is hollow and contains a structure called the central canal, which contains cerebrospinal fluid. The spinal cord is also covered by meninges and enclosed by the neural arches. Together, the brain and spinal cord make up the central nervous system. In humans, the spinal cord is a continuation of the brainstem and anatomically begins at the occipital bone, passing out of the foramen magnum and then enters the spinal canal at the beginning of the cervical vertebrae. The spinal cord extends down to between the first and second lumbar vertebrae, where it tapers to become the cauda equina. The enclosing bony vertebral column protects the relatively shorter spinal cord. It is around long in adult men and around long in adult women. The diam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Propriospinal Tract
Ventral propriospinal tract is a collection of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. It is a component of the white anterior columns. The fibers are largely myelinated and run close to the spinal central gray for the length of the cord. Shorter fibers are closer to, longer fibers further from the gray. Other prominent components of the anterior columns are the medial longitudinal fasciculus of the spinal cord, the anterior spinothalamic tract of the spinal cord and the lateral vestibulospinal tract of the spinal cord. The ventral propriospinal tract is one of three propriospinal tracts Propriospinal tracts are three tracts, collections of nerve fibers ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. They are located in the white columns ( funiculi) of the spinal cord where the colu ... in which most pathways intrinsic to the spinal cord are located. The others ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Propriospinal Tract
The dorsal propriospinal tract is a collection of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. It is a component of the white posterior column. Myelinated fibers are located adjacent to the spinal central gray. Shorter fibers are closer to, longer fibers further from the gray. Some fibers are unmyelinated and scattered through the posterior column. The tract is one of three propriospinal tracts in which most pathways intrinsic to the spinal cord are located. The others are the ventral propriospinal tract and the lateral propriospinal tract Lateral propriospinal tract is a collection of nerve fibers, ascending, descending, crossed and uncrossed, that interconnect various levels of the spinal cord. Its fibers are largely myelinated. It is a component of the white lateral columns. Most .... References External links * More information aBrainInfo Central nervous system pathways {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
