1. LYMPHATIC SYSTEM

2. LYMPH NODE A: Medulla B: Cortex C: Lymph nodules D: Germinal center D A B C

3. A B

4. A B C D

5. GERMINAL CENTER A B A: Cortex of lymph nodule B: Germinal center

6. A

8. PEYER’S PATCH A B C D A: Mucosa of the ileum. B: Submucosa C: Peyer’s Patches D: Germinal center.

11. APPENDIX A B C C D D A: Invagination of the mucosa. B: Simple columnar epithelium. C: Lymphatic Nodule D: Germinal Center

13. SPLEEN A D B A A C A: White pulp B: Red pulp C: Trabecula D: Germinal Center.

14. A C B C

16. THYMUS A B C D E A: Cortex B: Medulla. C: Lobules of the thymus. D: Interlobular septa E: Hassall’s corpuscle.

17. A B B C

18. A B C

19. TONSIL A B C A: Lymph Nodule B: Germinal center C: Stratified squamous epithelium

20. A B

21. LYMPHATIC VESSEL AB A: Lymphatic vessels are lined with endothelium which is simple squamous epithelium. B: Lymphatic valve