Final answer:
The spleen is the lymphoid tissue/organ that removes defective red blood cells from the blood. It consists of red pulp and white pulp, where damaged red blood cells are removed and replaced by new ones, and lymphocytes remove antigen-coated bacteria from the blood.
Step-by-step explanation:
The spleen removes defective red blood cells from the blood. It is a secondary lymphoid organ that functions as a filter for pathogens from the blood.
Within the spleen, there are two types of tissue: red pulp and white pulp. The red pulp consists of cavities that store blood, where damaged red blood cells are removed and replaced by new ones. The white pulp is rich in lymphocytes which remove antigen-coated bacteria from the blood.