Components of immune system

• (1) Lymphoid organs and tissues
• (2) Lymphoid cells：
• (3) Secretary matter：

Primary lymphoid organs and tissues

Function： providing developmental circumstance for lymphoid cells.

Members:

• Bone marrow

Thymus

Bursa of Fabricus (avian)

Secondary lymphoid organs and tissues

• Lymph

• Spleen（脾）

• Mucosa-associated lymphoid tissue(MALT)

  Adenoid腺样
  

1. Lymphatic system

• Lymphatic vessel
• Lymphatic duct
• Lymph : fluid component seeping from capillary into the surrounding tissue, while some flowing into the lymphatic capillary.

• Evolution of immune system