Removal of this organ from 740 World War II veterans saw twice the incidence of cardiovascular disease, perhaps because it releases monocytes during stresses on the heart. This organ is either absent or multiply expressed in patients with Ivemark Syndrome. It is surrounded by protective fibroelastic and serous coats. Like the kidney, this organ possesses Malphigian corpuscles, which are lymphocyte-containing follicles within one type of tissue in it. This organ is under the left side of the diaphragm, and becomes sequestered when trying to clear sickled cells. The marginal zone separates this 
Removal of this organ from 740 World War II veterans saw twice the incidence of cardiovascular disease, perhaps because it releases monocytes during stresses on the heart. This organ is either absent or multiply expressed in patients with Ivemark Syndrome. It is surrounded by protective fibroelastic and serous coats. Like the kidney, this organ possesses Malphigian corpuscles, which are lymphocyte-containing follicles within one type of tissue in it. This organ is under the left side of the diaphragm, and becomes sequestered when trying to clear sickled cells. The marginal zone separates this organ's white and red pulp. For 10 points, name this lymphoid organ in which red blood cells are destroyed.
Removal of this organ from 740 World War II veterans saw twice the incidence of cardiovascular disease, perhaps because it releases monocytes during stresses on the heart.
 the spleen