* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Teacher`s guide
Survey
Document related concepts
Germ theory of disease wikipedia , lookup
Monoclonal antibody wikipedia , lookup
Lymphopoiesis wikipedia , lookup
DNA vaccination wikipedia , lookup
Vaccination wikipedia , lookup
Immunocontraception wikipedia , lookup
Herd immunity wikipedia , lookup
Social immunity wikipedia , lookup
Sjögren syndrome wikipedia , lookup
Molecular mimicry wikipedia , lookup
Immune system wikipedia , lookup
Polyclonal B cell response wikipedia , lookup
Adaptive immune system wikipedia , lookup
Adoptive cell transfer wikipedia , lookup
Hygiene hypothesis wikipedia , lookup
Cancer immunotherapy wikipedia , lookup
Innate immune system wikipedia , lookup
Transcript
SUBJECT GRADE LEARNING UNIT SCIENCE SCIENCE 9TH GRADE What is everything around us made of? TITLE OF LEARNING OBJECT How does your body defend itself from the attack of pathogens? CURRICULAR AXIS STANDARD COMPETENCIES Science and technology Curricular Horizon LEARNING OBJECTIVES To identify the basic concepts of pathogenicity and immunity associated to the generation of infections by pathogenic agents such as viruses and bacteria. To describe the principal forms of immunological protection in vertebrates. To distinguish how the different cells of the immune system differentiate and act in the production of the so-called immune response. To recognize how the mechanism of action of vaccines in the human body is. SKILLS/ KNOWLEDGE LEARNING FLOW To identify and explaining how the immune system responds to allergies and cancer. SKILL 1: Understand the concept of pathogenicity. SKILL 2: Identify some viruses and pathogenic bacteria. SKILL 3: Illustrate the principal forms of protection from diseases in vertebrates. SKILL 4: Explain how nonspecific defenses work. SKILL 5: Differentiate the cells that participate in the immune response. SKILL 6: Investigate the mechanism of action of vaccines. SKILL 7: Explain that allergies are badly directed immune responses. SKILL 8: Explain how cancer evades the immune response. Introduction Objetives Activities Activity 1. The concepts of pathogenicity and immunity ASSESSMENT GUIDELINE Activity 2. Forms of immunological protection in vertebrates Activity 3. The cells of the immune system Activity 4. Action of vaccines in the human body Activity 5. Immune system in response to allergies and cancer Abstract Homework Glossary This learning object seeks to help the teacher guide his teaching practice and achieve that his students understand in the best way the basic function of the immune system. It is focused specially in the human body and its ability to defend itself from pathogenic organisms. To achieve this comprehension, students must complete the different activities which will help them learn and understand the subject better. Stage Learning flow Teaching/Learning Activities Introduction Introduction The teacher gives a brief explanation to his students, starting with everyday situations that are related to the immune system and to how it is capable of defending us from different pathogenic microorganisms that may cause diseases. Once he/she is done, it may good for him/her to reflect on this subject with the students and relate it to different topics that have to do with the immune system, like, for example, stress and cancer. The teacher can complement these subjects with the following reading: Content The teacher presents the topic http://search.proquest.com/openview/4e809c2eb636f8833d56c2052d110 d5b/1?pq-origsite=gscholar First Activity Nowadays people talk about two public health issues associated to a same transmitting agent: the Aedes aegypti mosquito, which transmits the Chikungunya and Zika viruses. These viruses generate events of Recommended Resources Animation resource for the introduction. pathogenicity in human beings, and there isn’t a cure for either of them. Only people who have been infected have generated immunity from them. Activity 1 Exercise Carry out a survey with your classmates about the concepts of immunity and pathogenicity. Also, ask them what they know about Chikungunya and Zika. Did you know that…? Currently, scientists are developing preclinical tests for a possible vaccine against the Zika virus. These tests had a strong and long-lasting result in mice. Tests on humans are expected to be carried out before this year (2016) ends. Second Activity As said before, pathogenicity is a microorganism’s capacity to cause a disease. Nowadays, there are several examples of infectious diseases caused especially by microbiological pathogenic agents like viruses and bacteria. Exercise Make a crossword puzzle that includes all the following terms for infectious pathologies: Diseases caused by viruses: aids flu Ebola chickenpox measles Chikungunya Zika Diseases caused by bacteria: tuberculosis syphilis tetanus gingivitis cholera dengue fever leprosy Third Activity The fundamental role of the immune system is the body’s defense against a great variety of pathogenic agents, capable of generating diseases (pathogenicity) in the affected individual. This system has gone through evolutionary changes throughout history, which have made it more specialized and highly efficient, as it is today, producing immunity in the favored organism. Learning activity In groups, reflect upon the immunological mechanism that the individuals from the animal kingdom apparently benefit exclusively from. Additionally, think about and investigate how a person who was infected by some type of disease and who wasn’t previously vaccinated, suffers from that disease and survives, but never gets it again (consider especially the term “immunity” to address this topic). Content development as a conclusion Throughout this activity, we’ve been learning that the event of generation of any type of disease is known by the term of pathogenicity. Also, we have seen that there are mechanisms that allow to resist such microbiological invasion, through a specialized defense system known as immune system. This system brings immunity and is present in all individuals of the animal kingdom, but is known with greater depth in human beings. First Activity Humans as well as animals benefit from a specialized immune system which we don’t see in action every day. Even though we can only see this when we get sick, we must remember that the defense mechanisms (specific and nonspecific) are always active and in the defense process. Activity 2 Exercise Complete, in pairs, the following comparative chart. To do this, you must investigate and look further into the characteristics of the innate and adaptive immunities: Characteristics Specificity Diversity Memory Components Physical and chemical barriers Blood proteins Cells Did you know that…? Innate Immunity Adaptive Immunity In five liters of blood, the white blood cells represent only 1%. And even though this seems a small amount, in every microliter of blood there are between 5,000 and 10,000 leucocytes. Second Activity The fact that human beings belong to the group of vertebrates, allows them to have a very specialized and evolved immune system, with direct and indirect protection mechanisms. Exercise Next, groups of three students will organize and do a crossword puzzle, using the following information: Down 1. Direct action immune mechanism (Specific). 2. Type of immunity that acts as a first line of defense (Innate). 3. Process that some specialized cells carry out, which consists on “eating” strange particles that have been previously recognized (Phagocytize). 4. Barrier of a non-immunological type (Epithelium). 5. Mechanism of adaptive immunity which is generated as a response to infection after repeated exposure to one same microorganism (cellular memory). Across 1. Indirect action immune mechanism (Nonspecific) 2. Type of immunity that is generated as a response to infection (Acquired). 3. Pathogenic agents that cause a great number of diseases (Microorganisms). 4. Barrier of a non-immunological type (Mucosae). 5. Type of animals that benefit from a more evolved immune system (Vertebrates). Third Activity The specialized defense mechanisms of vertebrates have generated effective processes of immune response. When immunity is generated in an individual, after a process of recognition and response, it becomes “immunized” and will not fall again in the same infectious process generated by the same microorganism. Learning Activity There are many words associated to immune response, and for this reason sometimes this topic isn’t very clear. Individually investigate, from the point of view of immunity, the functional meaning of each one of the following terms, with respect to microorganisms: Specificity Diversity Cellular memory Specialization Auto limitation Content development as a conclusion Throughout the activities that we’ve carried out, we’ve seen in a general way how the different strategies and mechanisms in the immune system of vertebrates are, especially in the human body. Their purpose is to help us not get sick, despite of all of the microbiological threats that surround us. First Activity The evolution of the immune system brings with it the molecular and cell specialization of such system. For this reason, we can find other types of cells capable of complementing the specific immune response towards all pathogens capable of generating infections. Exercise Elaborating a diagram that shows and identifies the origin or lineage of the five types of cells that make part of the white blood cells or leucocytes (neutrophils, lymphocytes, monocytes, eosinophils and basophils). Did you know that..? The cells called phagocytes (monocytes), are filled with lysosomes, which, upon entering a pathogenic agent, secrete the totality of their enzymes and this way degrade the invasive agent. Activity 3 Second Activity The main cells that generate the specific defense mechanism are called lymphocytes, which divide into T and B lymphocytes depending on their function and specificity. These cells are responsible for the immune response in the human body and have been affected by evolutionary processes which have implied a production of a marked functionality and efficacy in the immune processes. Exercise Solve, individually, the following ten statements, which refer to specialized cells in the immune system. Choose if each statement is True or False. For this, it is important for you to read the previous information. True/False questions ( F ) Lymphocytes are specific cells that don’t recognize nor differentiate antigens. ( T ) Phagocytes are in charge of phagocytizing previously recognized strange particles. ( T ) T and B lymphocytes are the only cells that participate in the specific corresponding immune response. ( F ) Only B lymphocytes originate in the bone marrow. ( F) B lymphocytes intervene in the so-called immune response through adaptive immunity. ( T ) The cells that stand out for being the only capable of producing antibodies are B lymphocytes. ( F ) The cells in charge of presenting the corresponding antigen, for its posterior recognition, are B lymphocytes. ( F ) T lymphocytes are cells that generate and produce cellular memory. ( T ) Both T and B lymphocytes are in charge of coordinating and mediating the immune response. ( T ) White blood cells are also called leucocytes. Third Activity There are other types of cells in the immune system that complement, in one way or another, the work of immune response. These cells are known as granulocytes and are also present in the bloodstream. Exercise In pairs, investigate the function that the rest of the cells (granulocytes) of the immune system have in the body. These cells are the following: Neutrophils Basophils Eosinophils Content development as a conclusion The main cells of the immune system are lymphocytes, which generate the immune response, which is the defense response that these cells carry out and which makes the mechanism to be divided in two parts: The innate response, which is represented by the antibodies produced by B lymphocytes. The cellular response, provided by the T lymphocytes. First Activity The effectiveness of vaccination is very important, since through this technique some of the worst infectious diseases have been eradicated almost by 100%. These diseases, years ago, caused high death rates at a global level. Exercise Working in pairs, investigate what the following diseases, which were eradicated thanks to the good use of vaccination, consisted in: Smallpox Poliomyelitis Pertussis Diphtheria Did you know that…? Currently, there are investigations that actively look for new types of vaccines, like the ones called DNA vaccines, made by a fragment of DNA, capable of codifying a protein antigen of the microorganism. The DNA enters the cells and induces the production of the protein which immunizes the vaccinated person. Second Activity Activity 4 Currently, there are several types of vaccines that meet their task of inducing immunity to those who receive them. They have been created through different tests and medical-scientific strategies. Exercise This next chart shows the types of vaccines that exist today. Write, in front of each type, two examples that still exist. Type of vaccine Dead or live attenuated bacteria Live attenuated virus Subunit vaccines Conjugate vaccines Synthetic vaccines Viral vectors DNA vaccines Examples Content development as a conclusion Even though in these times many great prevention and health promotion campaigns have been carried out, as well as restrictions to inadequate use of antibiotics and promotion of a larger awareness of the importance of vaccination, infectious diseases continue to be an important cause of sicknesses and deaths in the entire world. First Activity Allergies can happen to any individual, reacting to different environmental agents like pollen and bee stings or to some antibiotics. All of these disorders are related to the activation of certain cells of the immune system, as a reaction to an antigen, which triggers the disease immediately. Exercise Taking into account that asthma is an allergy that produces breathing difficulties, investigate how inhalers and bronchodilators work to help control this disease. This investigation must be carried out in pairs. Did you know that…? The earliest description of cancer was found in an Egyptian papyrus which is approximately from the year 3000 B.C. Second Activity Exercise Write a reflection on the importance of the breast self-exam, as a breast cancer prevention method, taking the following reading (Profamilia, 2016) as a reference: Activity 5 BREAST CANCER What is breast cancer? Breast cancer is a malignant tumor that originates in the cells of the breast. A malignant tumor is a group of cancer cells that can grow, penetrating (invading) the surrounding tissue, or that can spread (metastasize) to distant areas of the body. This disease occurs almost exclusively in women, but men can also get it. Types of breast cancer: Breast cancer can be divided into different types, according to how the shapes of the cancer cells look from a microscope. Most of the breast cancers are carcinomas, a type of cancer that starts in the cells that coat the organs and tissues (epithelial cells), like the breast. In fact, breast cancers are often a type of carcinoma called adenocarcinoma, which is the carcinoma that starts in glandular tissue. Other types of cancer can also occur in the breast, like sarcomas, which start in the cells of muscles, fat and connective tissue. Symptoms: The first recognizable symptom of breast cancer is usually a lump that feels different than the rest of the breast tissue. Prevention and early detection: A way to detect breast cancer early is through the breast self-exam, which consists of an examination that women make of their own breasts to detect if they have any abnormalities. The self-exam must be made as a part of the integral self-care of each woman. She can do it herself once a month, from five to seven days after her period, when there’s less tension in the breast. This must be done to prevent or detect breast cancer on time. Third Activity Exercise Working in pairs, do a word search puzzle which includes the following terms, associated to pathologies related to allergies and cancer: allergy basophil mast cell antigen rhinitis cancer immunosuppressant allergen pollen immunoglobulins mutation mitosis tumors immunovigilance Abstract Abstract Content development as a conclusion Cancer and its appropriate comprehension have been studied for many years. The main alteration caused by this disease is the uncontrolled proliferation of cancer cells and the great risk of metastasis (propagation of cancer cells to different parts of the body). Nowadays the topic is well known, but a definitive cure to treat this pathology hasn’t been found. The immune system is a group of specialized cells and molecular structures (antibodies) that use organized processes to defend the body from external pathogens. These pathogens can cause damage or disease in the individual. Pathogenicity is a microorganism’s ability to cause a disease. In its turn, the disease causes a strong imbalance in the affected individual; it generates physiological problems, producing symptoms and characteristics that are representative of the associated pathology. In nature, there’s a great diversity of beings that have the characteristic of being microbiological pathogenic agents. The most well-known are: viruses, bacteria, fungi and parasites. In vertebrates, we speak mainly of two defense mechanisms: specific and nonspecific. The specific includes two methods of defense or protection from some diseases: innate and adaptive immunity. Innate immunity is the first line of defense against microorganisms (skin and some specialized cells that phagocytize). Adaptive immunity is generated as a response to infection, after repeated exposure to the same microorganisms (cellular memory). On the other hand, there’s the nonspecific defense mechanism, which acts indirectly as a barrier against any type of external invasion, without specifically attacking any pathogen coming from outside. The most relevant defense is that of: skin, mucosae and their corresponding secretions (of acid), cilia and saliva. The cells that participate in the specific immune response are specially the so-called T and B lymphocytes. T lymphocytes are cells that mediate the immune response by presenting the antigen, while B lymphocytes are capable of producing antibodies and possess cellular memory. Vaccination is a method to provide immunity from some infections to individuals, in order to prevent certain types of disease. Vaccines provide immunity through the stimulation of effector and memory cells. The majority of the vaccines bring about adaptive immunity, since the event happens as a response to the infection. Allergies are badly directed immune responses, since they promote the activation of specialized cells, induced by a specific antigen which generates the disease. Among the most common pathologies are asthma, rhinitis and hives. Homework Homework Cancer evades the immune response through several specialized mechanisms: regulating the expression of molecules, selecting cells so that they don’t express tumor antigens and producing immunosuppressive substances that generate tolerance to the antigens that are formed in the cells. In groups of six students, make a creative and illustrative video to present to the other classmates. The video must show, in detail, the work carried out by the immune system. The content of the unit must be taken into account, as well as the goals mentioned in the beginning, to explain and clarify the following to the rest of the class: 1. The concept of immunity and the danger of being infected by virus and bacteria. 2. The specialized forms of immune protection in the human being. 3. How the immune response works, through the action of different types of cells. 4. How vaccines act in the human body. 5. How the immune system acts when allergies and cancer arise. This activity can be graded and must meet the five points written above. Students can use the following links as guides, since they can give them further information about these topics: http://www.medigraphic.com/pdfs/revmexneu/rmn-2006/rmn061f.pdf http://www.ucm.es/BUCM/revistasBUC/portal/modulos.php?name=Revista s2&id=RCCV&col=1 Evaluation Evaluation http://www.academia.edu/18429840/El_Sistema_Inmune_Innato_II_la_p rimera_respuesta_frente_a_la_infecci%C3%B3n The following is a test which means to evaluate the student’s performance in relation to the studied unit, through 15 basic questions. This test includes different types of questions. First, there are true/false questions, then multiple choice and finally a matching exercise. For this test, students must understand all the content presented in this learning object. I. CHOOSE TRUE (T) OR FALSE (F), DEPENDING ON THE CASE. 1. Pathogenicity is the microorganism’s ability to cause a disease. A. True B. False Answer key: A Feedback: This is the most appropriate definition referring to this term. 2. Two examples of pathogenic agents in nature are bacteria and viruses: A. True B. False Answer key: A Feedback: Yes. However, there are also fungi and parasites, which can cause pathogenicity as well. 3. The immune response in vertebrates is mediated mainly by two types of immunity: innate and natural. A. True B. False Answer key: B Feedback: No, since there are also nonspecific defenses, like mucosae and skin, which help as an indirect immunological mechanism. 4. The great majority of vaccines induce adaptive immunity in the human body. A. True B. False Answer key: A Feedback: Vaccines always generate this type of immunity. 5. In allergies like asthma and diseases like cancer, the immune response that is generated is the same. A. True B. False Answer key: B Feedback: The response is different since allergies cause immediate hypersensitivity that generates antibodies, while in cancer we’re dealing with adaptive immunity. II. CHOOSE QUESTIONS: THE CORRECT ANSWER FOR THE FOLLOWING 6. Which of the following diseases is produced by a bacteria as the pathological agent? A. zika B. aids C. chikungunya D. cholera Answer key: D Feedback: Cholera is a disease generated by the Vibrio cholerae bacteria. 7. Nonspecific defenses act indirectly to protect the human body. Of the following options, which make part of this defense system? A. secretions B. T lymphocytes C. antibodies D. B lymphocytes Answer key: A Feedback: Secretions are indirect methods of immunity, which don’t depend on the action of cells like lymphocytes, nor on antibodies. 8. Which of the following cells are present in the immune system? A. red blood cells B. osteocytes C. white blood cells D. antibodies Answer key: C Feedback: White blood cells or leucocytes are the only cells in the immune system, including neutrophils, basophils, eosinophils, monocytes, and lymphocytes. 9. Through which immunity do the great majority of vaccines act? A. natural B. adaptive C. nonspecific D. innate Answer key: B Feedback: Vaccines generate protection through the stimulation of the development of cells that provide cellular memory. 10. Allergies are badly directed immune responses, since they promote the activation of certain specialized cells, induced by a specific antigen that generates the disease. What is this antigen called? A. T lymphocyte B. antibody C. allergen D. B lymphocyte Answer key: C Feedback: The allergen is a specific antigen that produces antibodies. 11. Immunovigilance is a process that is carried out, mainly, to prevent the production of cells that can contain some type of mutation. Of the following diseases, which one is most linked to this concept of immunovigilance? A. aids B. asthma C. cholera D. cancer Answer key: D Feedback: This is an early recognition of potential cells that may form tumors eventually. III. MATCH. PLACE THE LETTER THAT CORRESPONDS INSIDE THE PARENTHESES. A. Innate immunity B. Polio C. Acquired immunity D. Antigen Glossary antibody( D ) skin (A) lymphocytes ( C ) vaccine ( B ) Answer key: Innate immunity is related to the skin since it acts as a barrier method. Polio is a vaccine given to children, which prevents poliomyelitis. Acquired immunity works exclusively with T and B lymphocytes. Antigens form antibodies. Acquired Immunity: Mechanism that is generated as a response to Multimedia Glossary infection. Active immunoprotection: Lasting effect after being vaccinated. Allergens: Specific antigens, which generate diseases immediately. Allergy: Immediate hypersensitivity responses. Antibody: Molecule that is responsible for immunity. Antigens: Chemical structures that form antibodies. Asthma: Allergy that produces airway obstruction. B lymphocytes: Cells that are capable of producing antibodies and generate cellular memory. Bacteria: Unicellular pathologies. prokaryotic microorganisms that cause many Basophils: Specialized cells of the immune system that appear in greater quantities in inflammation processes. Cancer: Pathology associated to a high cellular proliferation, which is caused by a mutation that makes cells “immortal”. This uncontrolled process can generate metastasis. Cancer produces tumors in the zones where it appears. Cell: Morphological and physiological unit of all living beings. Cellular memory: Mechanism supplied by adaptive immunity, which generates the capacity of having available information about a past event of infection. Cilia: Specialized structures of cellular movement and protection. Cytotoxic T lymphocytes: They are in charge of destroying the infected cells. Disease: Pathology that causes imbalance in an organism. Fungi: Unicellular or multicellular eukaryotic organisms that are known for being opportunist. They also cause certain fungal pathologies. Granulocytes: Blood cells that belong to white blood cells (neutrophils, eosinophils, basophils). Hives: Skin disease that is caused by contact with an irritating agent. Homeostasis: The organisms’ capacity to maintain a balanced internal condition. Host: Organism that hosts another inside. Immune response: Coordinated response to an event of infection. Immune system: Organized group of molecular and cell structures, which uses specialized processes to help defend anorganism from pathogenic agents. Immunity: Protection from infectious diseases. Immunoglobulins: antibodies. Specialized chemical molecules that produce Immunovigilance: Process that is carried out to avoid the production of certain types of cancer cells. Innate immunity: microorganisms. First line of defense against the action of Leucocytes: Specialized cells of the immune system, better known as white blood cells. Major histocompatibility complex: Genes whose products are in charge of distinguishing what belongs to the human body and what is external. Mast cells: Specialized cells that act in allergic or inflammatory processes. Metabolism: Group of chemical reactions that happen in the organism or in one cell. Monocytes: Type of white blood cells that specialize in phagocytizing. Parasites: Individuals that live at the expense of other organisms. Pathogenic agents: Microorganisms or molecules that cause diseases. Pathogenicity: An organism’s ability to cause diseases. Pathology: Biomedical science that studies diseases. Phagocytes: Cells that specialize in phagocytizing. Phagocytosis: Process in which a cell “eats” or phagocytizes particles of the external environment. Red blood cells: Specialized cells that transport oxygen and carbon dioxide in the blood. They are also known as erythrocytes. Rhinitis: Allergic and inflammatory process of the mucous membrane inside the nose. T lymphocytes: Cells that mediate the immune response, since they present the corresponding antigen. Thymus: A gland of the human body, where T lymphocytes mature. Toxins: Molecules that can cause diseases in individuals. Vaccines: Substances that provide protection against some infections. They are given before the organism is attacked by the corresponding pathogenic microorganism. Virus: Obligate intracellular parasites that exist in RNA and DNA types. They cause many infectious/contagious diseases.