The correct answer are valves. As lymphnodes become larger and deeper they turn into lymph vessels that develop one-way valves. These valves prevent the back flow of blood throughout the vessel and ensure that the lymph only flows in one direction.
<span>Answer:The blood vessels in the brain are blocked.
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Vascular neurocognitive disorder
is a condition caused by reduction or blockage of the brain’s blood supply. Because of the lack of blood, a certain region of the brain was damaged, changing a person’s
brain functions.
Biologist study life at all levels of organization and complexity .atoms genes atom MOLECULE ,CELL,TISSUE,ORGANS,ORGANISM POPULATION, EARTH ,SOLAR SYSTEM AND GALAXIES