PART C: Assessments Complete the following statements: 1. Lymph nodes contain large numbers of white blood cells called invading microorganisms. A3 and macrophages that fight 2. The indented region where blood vessels and nerves join a lymph node is called the 3. Lymphatic that contain germinal centers are the structural units of a lymph node. 43 4. The spaces within a lymph node are called lymphatic _through which lymph circulates. AS 5. Lymph enters a node through a(an) lymphatic vessel. A3 6. The lymph nodes associated with the lymphatic vessels that drain the lower limbs are located in the region. A1 AJ PART D: Assessments Complete the following statements: 1. The thymus is located in the anterior to the aortic arch. A1 2. The is very large in a child and will atrophy in advanced age 43 3. The is the largest of the lymphatic organs. A1 4. A of connective tissue surrounds the spleen. 43 5. The tiny islands (nodules) of tissue within the spleen that contain many lymphocytes constitute the pulp. 43 6. The pulp of the spleen contains large numbers of red blood cells, lymphocytes, and macro- phages. 43 within the spleen engulf and destroy foreign particles and cellular debris. 43 8. The lymphoid organs in the pharynx (throat) that are possible infection sites are collectively called
