The spleen (blood filled) (40X)

This is the spleen. It is a vital lymphoid organ involved in immune response and blood filtration. Its histological structure is complex, consisting of two main regions: the white pulp and the red pulp. I strongly urge you to first take a look at another section of the spleen where most of the blood has been removed. In this way, it is easier to see all the important structures.

The spleen is enveloped by a dense, fibrous connective tissue layer known as the capsule, which contains smooth muscle cells. The capsule extends into the spleen as trabeculae, providing structural support and carrying blood vessels into the organ.