医学英语视听说（第二版）卢凤香-unit 5.pptxVIP

医学英语视听说(第二版)Unit Five Blood, Lymph and Immune SystemMedical English Communication: Listening and Speaking (2nd edition)1 ContentsPart I Introduction to the Immune SystemPart II Diseases Related to the Immune SystemPart III Celebrity and DiseasePart IV Medical Terminology Related to Blood, Lymph and the Immune System2Part V Further Thinking Part IVideo: Introduction to the Immune System3 Think and TalkThe main kinds of lymphocytes that attack foreign cells invading human body are B lymphocytes and T lymphocytes. B lymphocytes and T lymphocytes have different functions. B cells search out their targets and produce antibodies, while T cells, like the soldiers, destroy the invaders that the B cells have identified. So, based on different tasks, T cells actually can be divided into two types: helper T cells and killer T cells. Reference4 Think and TalkHelper T cells, with no cytotoxic activity regulate both the innate and adaptive immune responses, and help determine which immune responses the body makes to a particular pathogen. They just control the immune response by directing other cells to accomplish these tasks, but killer T cells destroy cells that are infected with viruses, or are otherwise damaged.Reference5 Task One: Blank Filling leukocytes phagocytes macrophages dendritic cells orchestratingWatch and Do(6) Infected(7) unique antigens(8) special proteins(9) cycle through(10) neutralized 6 Task Two: Error CorrectionThe immune system relies on millions of defensive white blood cells, also known as leukocytes that originate in our bone marrow.Antigens on the surface of pathogens and other foreign substances, betray the presence of invaders.Leukocytes can be classified into two main cellular groups, which coordinate a two-pronged attack: phagocytes and lymphocytes.Watch and Do7 Task Two: Error Correction4. High temperatures and swelling are actually processes designed to help the immune response. A warmer body makes it harder for bacter