Diseases And Immunity
Overview
Every day your body is exposed to microorganisms that could make you ill, yet most of the time you stay healthy. That is because you are protected on two fronts: physical and chemical barriers that keep pathogens out, and an immune system that destroys those that get in, and remembers them.
In this lesson you will learn what pathogens are, how diseases spread, and how good hygiene and clean water control them. Extended students will learn how antibodies and antigens work, how vaccination gives long-term immunity, and how passive immunity protects a newborn baby.
Objectives
- [Core] Describe a pathogen as a disease-causing organism
- [Core] Describe a transmissible disease as a disease in which the pathogen can be passed from one host to another
- [Core] State that a pathogen is transmitted: (a) by direct contact, including through blood and other body fluids (b) indirectly, including from contaminated surfaces, food, animals and air
- [Core] Describe the body defences against pathogens, limited to: skin, hairs in the nose, mucus, stomach acid and white blood cells
- [Supplement] State the features of viruses, limited to a protein coat and genetic material
- [Supplement] Explain the importance of the following in controlling the spread of disease: (a) a clean water supply (b) hygienic food preparation (c) good personal hygiene (d) waste disposal (e) sewage treatment (details of the stages of sewage treatment are not required)
- [Supplement] Describe active immunity as defence against a pathogen by antibody production in the body
- [Supplement] State that active immunity is gained after an infection by a pathogen or by vaccination
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Diseases And Immunity. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- A pathogen is best described as: A. a disease B. a disease-causing organism C. a type of antibody D. a white blood cell Answer: B
- Which is a chemical defence of the body against pathogens? A. skin B. nose hairs C. stomach acid D. mucus trapping only Answer: C
- [Supplement] Antibodies are produced by: A. red blood cells B. lymphocytes C. platelets D. plasma Answer: B
- [Supplement] Long-term immunity after vaccination is due to the production of: A. antigens B. memory cells C. platelets D. plasma Answer: B
- [Supplement] Immunity gained from antibodies in breast milk is an example of: A. active immunity B. passive immunity C. natural barriers D. phagocytosis Answer: B
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