Lymphatic  System

Encased in a capsule, it also contains a medulla and a cortex. Germinal centers stain lighter and are less densely packed. The lymphocytes in the germinal centers are larger.

http://www.lab.anhb.uwa.edu.au/mb140/CorePages/

Free circulating macrophages are found in the reticular network of each lymph node. They function to clear the lymph of pathogens

 http://www.lab.anhb.uwa.edu.au/mb140/CorePages/

(GC) Germinal centers are found in the cortex. The medulla contains macrophages, plasma cells and small lymphocytes.

http://www.cvm.okstate.edu/instruction/mm_curr/

 capsule (cap); connective tissue trabeculae (T)  lymphatic nodules or germinal centers (N)trabecular  sinuses  (TS)

http://www.anatomy.dal.ca/Human_Histology/Lab

Trabecula or cortical sinuses separate the lymphatic nodules (nodules contain germinal centers).

http://pleiad.umdnj.edu/hemepath/normal_node/

Lymph node showing the direction of lymph flow

http://science.nhmccd.edu/biol/lymphatic/lymph.htm

Lymphatic vessel containing a valve. The valve prevents lymph from backing up.

Red pulp consists of vessels of the central artery this is where macrophages remove worn our red blood cells and toxins. This is also where iron is recycled from the blood. This is not necessarily darker than the white pulp

White pulp consists of groups of lymphatic nodules and it is composed of lymphocytes. The white pulp has immune functions and depending on stain it may be darker than the red pulp

Connective tissue trabecula subdivides the thymus into lobules. The function of the Hassall’s corpuscle is unclear.

Luminal surface (interior epithelium) forms crypts that "catch" bacteria

Lymphatic nodules with germinal centers can be found along the crypts. These contain lymphatic cells.