spleen morphology trait spleen red pulp morphology trait Any measurable or observable characteristic related to the shape, structure, color, or pattern of the parenchymatous tissue network of the spleen that consists of loose plates or cords (sinuses) infiltrated with red blood cells where most of the blood filtration occurs and degenerate erythrocytes are removed from the circulation. Trait.ontology VT:0002356 splenic red pulp morphology trait