Final answer:
The spleen is located in the upper left quadrant of the abdominopelvic cavity, associated with the stomach and the left kidney, and serves as an essential lymphatic organ. It also acts as a blood filter, removing pathogens and outdated red blood cells.
Step-by-step explanation:
The spleen is a vital organ in the lymphatic system. It is located in the upper left quadrant of the abdominopelvic cavity, just below the diaphragm. This organ is closely associated with the stomach and the left kidney, and is connected to the stomach via the gastrosplenic ligament. The spleen acts as a blood filter, removing pathogens and worn-out red blood cells, thanks to its extensive vascularization and abundance of macrophages and dendritic cells. In addition, the spleen is integral to the immune response to blood-borne pathogens. It's crucial to note that the upper left quadrant, where the spleen resides, is part of the larger abdominopelvic cavity, which is further divided into nine regions and four quadrants to help localize anatomical structures.
Kehr's sign can be associated with a ruptured spleen, where blood released into the abdominopelvic cavity puts pressure on the diaphragm. This results in referred pain in areas corresponding to the diaphragm due to the close proximity of the spleen to this muscle.