BRAIN
SPINAL CORD
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It is concerned with exteroceptive stimuli.
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It is found in the posterior horn of the spinal cord
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In the upper two thoracic segments, it is called the spinal nucleus of trigeminal nerve.
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It is found downwards even below the second lumbar segment
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Detailed explanation-1: -Definition. Substantia gelatinosa is a collection of cells in the gray area (dorsal horns) of the spinal cord. Found at all levels of the cord, it receives direct input from the dorsal (sensory) nerve roots, especially those fibers from pain and thermoreceptors.
Detailed explanation-2: -Lamina 2, commonly known as the substantia gelatinosa, is a translucent layer defined by its lack of myelinated fibers. The neurons in lamina 2 are usually small, rounded or slightly elongated. Lamina 2 lies ventral to lamina 1 and consists of a dorsal outer zone (lamina 2o) and a ventral inner zone (lamina 2i).
Detailed explanation-3: -The nucleus proprius is a layer of the spinal cord adjacent to the substantia gelatinosa. The nucleus proprius can be found in the gray matter in all levels of the spinal cord. It constitutes the first synapse of the spinothalamic tract carrying pain and temperature sensations from peripheral nerves.