The Body's Defense System PDF
Document Details
Uploaded by TopsFluorine
Tags
Summary
This document discusses the body's defense systems, including physical barriers, mechanical defenses, and cellular and fluid components. It explains the primary and secondary immune responses and how to strengthen one's immune system. The document is suitable for a secondary school biology lesson.
Full Transcript
CEP - MED THE BODY'S DEFENSE SYSTEM MS. PIA CINCO Unit 1: Lesson 2 MR. FRANCIS MAXIMILIAN ILAGAN The Body's Defense System BLACK DEATH THE BUBONIC PLAGUE LESSON OBJECTIVES Analyze the components of the external and internal defense syste...
CEP - MED THE BODY'S DEFENSE SYSTEM MS. PIA CINCO Unit 1: Lesson 2 MR. FRANCIS MAXIMILIAN ILAGAN The Body's Defense System BLACK DEATH THE BUBONIC PLAGUE LESSON OBJECTIVES Analyze the components of the external and internal defense systems Describe the function of antibodies during a primary and secondary immune response Develop measures in strengthening one’s immune system FIRST SECOND LINE LINE OF DEFENSE OF DEFENSE PHYSICAL CHEMICAL CELLULAR Enzymes Physical barriers Granulocytes Antimicrobial peptides Mechanical defenses Plasma protein mediators Agranulocytes Microbiome Cytokines Inflammation-eliciting mediators PHYSICAL BARRIERS Preventing microbes from reaching tissues that are susceptible to infection. Cellular level: tight gap-to-gap junctions MECHANICAL DEFENSES Epidermis consists of cells packed with KERATIN -mechanically tough and resistant to bacterial enzymes FATTY ACIDS - create dry, salty, acidic environment inhibiting microbial growth SEBUM - seals off pores of the hair follicle MECHANICAL DEFENSES Our eyes have two openings called LACRIMAL PUNCTUM Tears contain defensins lactoferrin lysozyme MECHANICAL DEFENSES MUCOUS MEMBRANES cover and protect cells beneath it by trapping debris and particulate matter, including microbes Ex: Mucociliary blanket; mucociliary escalator MECHANICAL DEFENSES Microbiomes protect through taking up cellular binding sites competes for available nutrients Thus, the pathogens cannot colonize! CHECKPOINT! How does our skin protect us from pathogens? How can we differentiate our body's defense systems? CELLS AND FLUIDS 1.Acute-Phase Proteins produced in the liver and secreted into the blood in response to inflammatory molecules from the immune system the chemical structures of these proteins inhibits or destroys microbes CELLS AND FLUIDS CELLS AND FLUIDS 2.Cytokines soluble proteins that act as communication between cells Interferons Interleukins Chemokines inhibit viral stimulate recruits leukocytes replication and leukocytes to help to sites of production of with the immune infection, tissue mature virus by response damage, and stopping its gene inflammation replication CELLS AND FLUIDS 3.Granulocytes are WBCs that have granules in them. These fight off infections Basophils and Neutrophils Eosinophils Mast Cells elimination and protect against responds to destruction of protozoa and inflammation and extracellular helminths; play in allergic responses bacteria through allergic reactions by releasing phagocytosis histamine CELLS AND FLUIDS 3.Agranulocytes are WBCs that do not have granules in them. Monocytes enter the tissues, Natural Killer Cells they differentiate into tissue- directly attack or specific phagocytes called destroy other cells macrophage and dendritic cells CELLS AND FLUIDS HOW DOES OUR BODY RESPOND TO PATHOGENS? Let's discuss our immune system! ADAPTIVE IMMUNITY Memory Specificity ability to quickly the ability respond to pathogens to target it has been previously specific pathogens exposed to ADAPTIVE IMMUNITY involves two distinct cell types B Lymphocytes T Lymphocytes mediate humoral drive cellular immunity in the immunity when spaces between other pathogens are found cells within the cells LYMPHOCYTES' GOAL during development, lymphocytes must be Immunocompetence Self-Tolerance each lymphocyte must each lymphocyte must be become able to recognize relatively unresponsive to its one specific antigen by self-antigens so that it binding to it does not attack the body's own cells IMMUNOLOGICAL MEMORY how do these lymphocytes respond to pathogens? Primary Immune Secondary Immune Response Response cellular proliferation faster, more prolonged, and differentiation and more effective lymphocytes transform "on alert" into plasma cells (effector cells) PRIMARY IMMUNE RESPONSE 1. Activation of Immune Response 2. Antigen Processing and Presentation 3. T-Cell Activation and Differentiation 4. Antibody Production of B-Cells 5. Peak of Immune Response ACTIVATION OF IMMUNE RESPONSE Antigen-presenting cells (APCs) detect and capture antigens. Ex: dendritic cell, a type of APC that patrols the body's tissues, seeking out foreign invaders. Once a dendritic cell encounters an antigen, it engulfs and processes the antigen, breaking it down into smaller fragments. ANTIGEN PROCESSING AND PRESENTATION The processed antigen fragments are then presented on the surface of the dendritic cell using molecules known as major histocompatibility complex (MHC) molecules. This presentation is essential for the activation of T-helper cells (CD4+), T-CELL ACTIVATION AND DIFFERENTIATION Upon activation, T-helper cells release signaling molecules called cytokines, which play a pivotal role in orchestrating the immune response These cytokines not only stimulate the proliferation of more immune cells but also trigger the activation of B cells, another key component of the adaptive immune system. ANTIBODY PRODUCTION BY B-CELLS Some B cells transform into plasma cells, which are factories specialized in producing antibodies. Antibodies, also known as immunoglobulins, are Y-shaped proteins that specifically recognize and neutralize antigens. PEAK IMMUNE RESPONSE Antibodies circulate through the bloodstream, targeting and binding to the antigens present on pathogens. Antibodies, also known as immunoglobulins, are Y-shaped proteins that specifically recognize and neutralize antigens. SECONDARY IMMUNE RESPONSE Memory cells are specialized immune cells that "remember" a pathogen's unique characteristics. Two main types of memory cells play pivotal roles: memory B cells and memory T cells. Mahalingam, Sundarasamy & Peter, John & Xu, Ziyang & Bordoloi, Devivasha & Ho, Michelle & Kalyanaraman, Vaniambadi & Srinivasan, Alagarsamy & Muthumani, Kar. (2021). Landscape of humoral immune responses against SARS-CoV-2 in patients with COVID-19 disease and the value of antibody testing. Heliyon. 7. e06836. 10.1016/j.heliyon.2021.e06836. Deebak, P. & S.S. College. (n.d.). Understanding Immunity (Vol. 4). https://www.sscollegejehanabad.org HOW CAN WE STRENGHTEN OUR DEFENSE SYSTEMS? Write three steps you can make to improve our body's defense systems. As a class, compile it and make a "Healthy Habits" poster and place it at the bulletin board of your classrooms.