Chapter 7: Human Health and Disease

Biology • Class 12

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Chapter Analysis

Intermediate19 pages • English

Quick Summary

The chapter 'Human Health and Disease' explores various aspects of human health, including the physiological and societal impacts of diseases. It discusses common diseases, both infectious and non-infectious, their transmission, prevention, and treatment. Key topics include the immune system, AIDS, cancer, and the abuse of drugs and alcohol. The chapter emphasizes the importance of lifestyle choices, the role of public health measures, and the advancements in medical science for disease control.

Key Topics

  • Common diseases in humans
  • Immunity and immune responses
  • HIV/AIDS transmission and prevention
  • Cancer mechanisms and control
  • Drug and alcohol abuse
  • Vaccination and its role
  • Lifestyle impacts on health
  • Public health measures

Learning Objectives

  • Understand the mechanisms of common infectious diseases and their transmission
  • Describe the components and functions of the immune system
  • Recognize the causes and consequences of AIDS and cancer
  • Identify the effects of drug and alcohol abuse and methods of prevention
  • Apply knowledge of vaccines in disease prevention strategies
  • Evaluate the importance of public health measures in controlling disease spread

Questions in Chapter

What are the various public health measures, which you would suggest as safeguard against infectious diseases?

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In which way has the study of biology helped us to control infectious diseases?

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How does the transmission of each of the following diseases take place? (a) Amoebiasis (b) Malaria (c) Ascariasis (d) Pneumonia

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What measure would you take to prevent water-borne diseases?

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Discuss with your teacher what does ‘a suitable gene’ means, in the context of DNA vaccines.

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Name the primary and secondary lymphoid organs.

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The following are some well-known abbreviations, which have been used in this chapter. Expand each one to its full form: (a) MALT (b) CMI (c) AIDS (d) NACO (e) HIV

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Differentiate the following and give examples of each: (a) Innate and acquired immunity (b) Active and passive immunity

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Draw a well-labelled diagram of an antibody molecule.

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What are the various routes by which transmission of human immuno-deficiency virus takes place?

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What is the mechanism by which the AIDS virus causes deficiency of immune system of the infected person?

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How is a cancerous cell different from a normal cell?

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Explain what is meant by metastasis.

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List the harmful effects caused by alcohol/drug abuse.

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Do you think that friends can influence one to take alcohol/drugs? If yes, how may one protect himself/herself from such an influence?

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Why is that once a person starts taking alcohol or drugs, it is difficult to get rid of this habit? Discuss it with your teacher.

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In your view what motivates youngsters to take to alcohol or drugs and how can this be avoided?

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Additional Practice Questions

What role does the immune system play in preventing disease?

easy

Answer: The immune system provides defense by responding to pathogens through innate and acquired immunity, thereby preventing disease.

Explain the concept of acquired immunity with examples.

medium

Answer: Acquired immunity develops after exposure to a disease or through vaccination. It involves the production of specific antibodies that remember the pathogen for future defense.

How can lifestyle choices impact the risk of cancer?

medium

Answer: Lifestyle choices such as smoking, diet, alcohol consumption, and exposure to carcinogens can increase the risk of cancer by damaging DNA and affecting cellular mechanisms.

Describe the process and importance of vaccination in disease prevention.

easy

Answer: Vaccination involves introducing a pathogen's antigen to stimulate antibody production without causing disease, thus preparing the immune system for future encounters with the actual pathogen.

What are the risks associated with drug and alcohol abuse?

hard

Answer: Drug and alcohol abuse can lead to addiction, health issues such as liver damage, impaired cognitive function, and social problems.

Discuss the societal impacts of infectious diseases.

medium

Answer: Infectious diseases can cause widespread illness and death, impacting economic productivity, increasing healthcare costs, and potentially leading to societal disruption.

How does HIV cause AIDS, and what are its effects on the immune system?

hard

Answer: HIV targets and destroys helper T-cells, leading to weakened immune responses and progression to AIDS, leaving the body vulnerable to opportunistic infections.

Why is mental health an important aspect of overall health?

medium

Answer: Mental health affects physical health, as stress and mental disorders can weaken the immune system and lead to physical health issues.

How can public health measures help control the spread of diseases like malaria?

hard

Answer: Measures like mosquito control, improved sanitation, vaccination, and public education reduce the spread of diseases like malaria by targeting vectors and improving resistance.

In what ways can early detection and prevention reduce cancer risks?

medium

Answer: Regular screenings, awareness of genetic predisposition, and lifestyle adjustments can help detect cancer early, improving treatment success rates and reducing risks.