Difference between a lymphatic organ and a lymphatic nodule

The organs- thymus, tonsil, appendix and spleen constructs the lymphatic organ system and the lymph nodule is the collection of small lymphoid tissue.

Explanation:

The most significant part of immune and vascular system is the Lymphatic system. This system is consisted of some organs, like- spleen, thymus, tonsil and appendix, mainly named as lymphatic organs. These organs contribute to the function of defend in the immune system.  

Lymph nodules, however, are the collective small lymphoid tissue. These nodules are found in the area that is exposed to microorganism and it helps in fighting them.  

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

it would be heredity