Biology never dies

1. Biology never dies By Dennis 文本

2. The innate and adaptive immune system Ding sheng report

3. 文本 细胞免疫：是由T-淋巴细胞产生的免疫，首先需要经过皮肤，吞噬细胞两道防线后，才可发生。吞噬细胞把抗原传给T-淋巴细胞，T-淋巴细胞分析后（受体与抗原结合），立即分化出记忆T细胞和效应T细胞，后着把侵入细胞内的病毒（或细菌）的细胞进行裂解，然后由吞噬细胞进行处理（对病毒细菌，主要通过溶酶体。） Human’s immune system

4. 文本 体液免疫：与细胞免疫一样，它的发生必须要经过过皮肤，吞噬细胞两道防线；体液免疫是由B-淋巴细胞产生的。首先，需要由吞噬细胞抗原承接给T-淋巴细胞好后，由T-淋巴细胞在转给B-淋巴细胞。B-淋巴细胞分化出记忆和效应B细胞，后者对体液中的细菌进行溶解，裂解，前者则记忆抗原蛋白。

5. the real part starts

6. the immune system plays an important role in homeostasis by maintaining animal health in both innate and adaptive ways . the innate system:the skin, scales is a barrier to infectious organisms. Mucus is a very effective chemical : mucus is secertly created by fish epithelial cells probably helps to trap microorganisms, and the mucus can contain antibodies and chemicals that destroy or inhibit bacteria . The volume of mucus secreted may increase in stressful situations, indicating a response on the fish’s part to shield itself form potentially harmful chemicals,microorganisms,or other agents。 agents

7. 文本 Other parts of innate response include inducible phagocytic cells that can attack and destroy potential pathogens, cytotoxic cells that destroy cells infected by viruses, and the complement system of proteins that attack the membrane of invading cells .

8. Adaptive immune system: The adaptive response include both cellular and humoral components.The cellular component of the adaptive response includes cytotoxic T cells that can destroy cells that have become infected by viruses or that show signs of becoming cancerous.

9. 文本 The humoral response involves the detection of specific invading compounds and the production of antibodies designed to bind to them. These antibodies tag the antigenic particles for destruction by other components of the immune system, such as macrophages that engulf and digest tagged cells by puncturing their membranes.

10. 文本 Thanks for watching!