reticular1(redirected from reticular1 activating system)
resembling a net.
reticular1 activating system
the system of cells of the reticular formation of the medulla oblongata that receive collaterals from the ascending sensory pathways and project to higher centers; they control the overall degree of central nervous system activity, including wakefulness, attentiveness and sleep; abbreviated RAS. Called also ascending reticular formation.
ascending reticular1 formation
see reticular activating system (above).
stellate cells that form the reticular fibers of connective tissue; they form the supporting framework of bone marrow, lymph nodes, lymphatic nodules, spleen and tonsils.
reticular1 colliquation, epidermal reticular1 degeneration
severe intracellular edema of epidermal cells, characterized by the degeneration of cells to form reticulated septa separating lobules of fluid.
descending reticular1 system
a diffuse motor control mechanism which descends from the midbrain to lower motor neurons in the brainstem and spinal cord.
a congenital error in stem cell numbers in the bone marrow; a rare cause of anemia.
see ascending reticular formation, reticular activating system (above).
medullary reticular1 formation
see ascending reticular formation (above).
reticular1 tissue, reticulated tissue
connective tissue composed predominantly of reticulum cells and reticular fibers.