1. LOCATION:
An unpaired, soft abdominal organ situated on the left between
the stomach, L. kidney and the diaphragm. Adapted to filter
and store blood.
2. ORGANIZATION:
Highly organized ovoid organ: Capsule of D.I.FECT
with visceral peritoneum (mesothelium); Trabeculae -- D.I.-FECT;
White Pulp of lymphocytes;
Red pulp -- of pulp cords
and splenic sinuses. Complex vascular system; Lymphatic vessels
in white pulp; Vasomotor and sensory nerve fibers.
3. STROMA:
Reticular C.T. of reticular cells and fibers
(mesodermal origin); associated with macrophages. The reticulum
supports both white pulp and red pulp. The reticular fibers
are continuous with the fibers of trabeculae and the supporting
reticular lamina of the walls of sinuses.
4. PARENCHYMA:
Lymphocytes form the elongate, branched strands
of white pulp, which contain nodules with germinal centers;
Erythrocytes, lymphocytes, plasma cells, monocytes, macrophages
and sometimes megakaryocytes are present in the red pulp.
5. DIAGNOSTIC
FEATURES: Red pulp and arrangement of white
pulp (See Figure 2):