Class 8 Science Health The Ultimate Treasure


1. Introduction

Health is not just the absence of disease; it is a state of complete physical, mental, and social well-being. Healthy individuals can live fully, work efficiently, and contribute to society.

Maintaining health requires personal hygiene, proper diet, exercise, and awareness of diseases.


2. Components of Good Health

  1. Physical Health
    • Regular exercise and proper sleep.
    • Balanced diet with essential nutrients.
    • Avoiding harmful substances like tobacco and alcohol.
  2. Mental Health
    • Positive thinking and stress management.
    • Adequate rest and relaxation.
    • Engaging in hobbies and social activities.
  3. Social Health
    • Good relationships with family and friends.
    • Respect for others and teamwork.
    • Active participation in community activities.

3. Factors Affecting Health

  • Genetic Factors: Inherited conditions or traits.
  • Environmental Factors: Clean air, water, and surroundings.
  • Lifestyle Factors: Exercise, diet, and habits.
  • Economic and Social Factors: Access to healthcare and education.
  • Diseases: Infectious and non-infectious diseases affect health.

4. Personal Hygiene

  • Washing hands before meals and after using the toilet.
  • Bathing regularly and keeping clothes clean.
  • Brushing teeth twice a day.
  • Keeping nails trimmed.
  • Avoiding contact with sick individuals when contagious.

5. Infectious and Non-Infectious Diseases

Infectious Diseases

  • Caused by microorganisms (bacteria, viruses, fungi, protozoa).
  • Spread through air, water, food, or direct contact.
  • Examples: Tuberculosis, Malaria, Influenza.
  • Prevention: Vaccination, hygiene, and sanitation.

Non-Infectious Diseases

  • Not caused by microorganisms.
  • May result from genetics, lifestyle, or environment.
  • Examples: Diabetes, Heart disease, Cancer.
  • Prevention: Healthy diet, exercise, avoiding smoking and alcohol.

6. Immunity and Vaccination

  • Immunity: The body’s ability to resist disease.
  • Vaccines: Substances that stimulate immunity against specific diseases.
  • Examples: Polio, Measles, Hepatitis B vaccines.

7. Nutrition and Health

  • A balanced diet includes carbohydrates, proteins, fats, vitamins, minerals, and water.
  • Malnutrition can lead to stunted growth, weak immunity, and health problems.
  • Eating fresh fruits, vegetables, and drinking clean water improves overall health.

8. Health and Lifestyle Tips

  • Exercise regularly (e.g., walking, yoga, sports).
  • Maintain a balanced diet.
  • Get adequate sleep (7–8 hours daily).
  • Avoid smoking, alcohol, and junk food.
  • Practice personal hygiene.
  • Reduce stress through hobbies and relaxation.

9. Key Terms

TermMeaning
HealthState of physical, mental, and social well-being
HygienePractices that maintain health and prevent disease
Infectious DiseaseDisease caused by microorganisms and can spread
Non-Infectious DiseaseDisease not caused by microorganisms
ImmunityBody’s ability to resist diseases
VaccinationAdministration of a vaccine to develop immunity

Questions

Very Short Answer Questions

  • Define health.
  • Name one infectious and one non-infectious disease.
  • What is personal hygiene?
  • Give one example of a vaccine.
  • Mention one factor affecting health.

Short Answer Questions

  • Explain the three components of good health.
  • List four personal hygiene practices.
  • Distinguish between infectious and non-infectious diseases.
  • How does vaccination help in disease prevention?

Long Answer Questions

  • Discuss the importance of nutrition and exercise in maintaining health.
  • Explain how lifestyle and environment affect our health.
  • Describe the role of hygiene and sanitation in preventing diseases.
  • Discuss how mental and social health contribute to overall well-being.

Multiple Choice Questions

  • Health is a state of:
    a) Physical well-being only
    b) Mental well-being only
    c) Complete physical, mental, and social well-being
    d) Absence of disease
    Answer: c
  • Polio vaccine helps in:
    a) Treating polio
    b) Preventing polio
    c) Spreading immunity to others
    d) Killing bacteria
    Answer: b

Fill in the Blanks

  • Balanced diet includes carbohydrates, proteins, fats, vitamins, and minerals.
  • Hygiene helps prevent diseases.
  • Vaccines help develop immunity.
  • Exercise and proper sleep maintain physical health.
  • Infectious diseases are caused by microorganisms.

True/False Questions

  • Health is only the absence of disease. False
  • Personal hygiene is important for good health. True
  • Diabetes is an infectious disease. False
  • Vaccines prevent specific diseases. True

Match the Following

Column AColumn B
ImmunityAbility to resist disease
VaccineStimulates immunity
HygieneCleanliness practices
DiabetesNon-infectious disease
InfluenzaInfectious disease

MCQs

  1. Health is a state of:
    a) Absence of disease
    b) Physical, mental, and social well-being
    c) Only physical fitness
    d) Only mental fitness
    Answer: b
  2. Physical health includes:
    a) Balanced diet and exercise
    b) Good relationships
    c) Stress management
    d) Social participation
    Answer: a
  3. Mental health can be maintained by:
    a) Stress management
    b) Smoking
    c) Ignoring hobbies
    d) Overworking
    Answer: a
  4. Social health means:
    a) Avoiding people
    b) Good relationships and teamwork
    c) Only physical fitness
    d) Being competitive
    Answer: b
  5. Which of these is a component of health?
    a) Physical health
    b) Mental health
    c) Social health
    d) All of the above
    Answer: d

Factors Affecting Health

  1. A factor affecting health is:
    a) Genetics
    b) Environment
    c) Lifestyle
    d) All of the above
    Answer: d
  2. Access to clean water is an example of a:
    a) Genetic factor
    b) Environmental factor
    c) Lifestyle factor
    d) Social factor
    Answer: b
  3. Poor diet can lead to:
    a) Malnutrition
    b) Immunity boost
    c) Mental alertness
    d) Better growth
    Answer: a
  4. Which is not a factor affecting health?
    a) Personal habits
    b) Environment
    c) Astrology
    d) Social status
    Answer: c
  5. Genetics influence health by:
    a) Determining hereditary traits and diseases
    b) Improving hygiene
    c) Giving immunity to all diseases
    d) None of the above
    Answer: a

Personal Hygiene

  1. Handwashing before meals prevents:
    a) Infectious diseases
    b) Malnutrition
    c) Non-infectious diseases
    d) Mental stress
    Answer: a
  2. Brushing teeth twice a day prevents:
    a) Heart disease
    b) Dental problems
    c) Malaria
    d) Diabetes
    Answer: b
  3. Nail trimming is part of:
    a) Personal hygiene
    b) Nutrition
    c) Immunity
    d) Vaccination
    Answer: a
  4. Bathing regularly helps:
    a) Maintain cleanliness and prevent infections
    b) Improve immunity directly
    c) Cure diabetes
    d) Make one taller
    Answer: a
  5. Which of these is not part of personal hygiene?
    a) Washing hands
    b) Bathing
    c) Nail trimming
    d) Smoking
    Answer: d

Infectious and Non-Infectious Diseases

  1. Infectious diseases are caused by:
    a) Microorganisms
    b) Pollution
    c) Bad habits
    d) Poor sleep
    Answer: a
  2. Non-infectious diseases are caused by:
    a) Bacteria
    b) Viruses
    c) Lifestyle or genetics
    d) Protozoa
    Answer: c
  3. Tuberculosis is caused by:
    a) Virus
    b) Bacteria
    c) Fungus
    d) Protozoa
    Answer: b
  4. Diabetes is an example of:
    a) Infectious disease
    b) Non-infectious disease
    c) Genetic disease only
    d) Mental disorder
    Answer: b
  5. Malaria is caused by:
    a) Virus
    b) Bacteria
    c) Protozoa
    d) Fungus
    Answer: c
  6. Influenza is caused by:
    a) Virus
    b) Bacteria
    c) Fungi
    d) Protozoa
    Answer: a
  7. Which is an infectious disease?
    a) Cancer
    b) Tuberculosis
    c) Diabetes
    d) Heart disease
    Answer: b
  8. Non-infectious diseases cannot spread from:
    a) Person to person
    b) Animals
    c) Environment
    d) All of the above
    Answer: a
  9. Which of the following is non-infectious?
    a) Malaria
    b) Diabetes
    c) Influenza
    d) Chickenpox
    Answer: b
  10. Infectious diseases can be prevented by:
    a) Vaccination and hygiene
    b) Poor diet
    c) Ignoring symptoms
    d) Exercise only
    Answer: a

Immunity and Vaccination

  1. Immunity is:
    a) Ability to resist diseases
    b) Infection of the body
    c) Poor health
    d) Exercise
    Answer: a
  2. Vaccines:
    a) Cure diseases
    b) Provide immunity against diseases
    c) Make diseases worse
    d) Replace medicine
    Answer: b
  3. Polio vaccine prevents:
    a) Heart disease
    b) Polio
    c) Malaria
    d) Diabetes
    Answer: b
  4. Hepatitis B vaccine protects against:
    a) Liver infection
    b) Flu
    c) TB
    d) Malaria
    Answer: a
  5. Vaccination is an example of:
    a) Artificial immunity
    b) Natural immunity
    c) Passive immunity
    d) None of the above
    Answer: a
  6. Immunity develops naturally when:
    a) Body fights infection
    b) Vaccinated
    c) Eating sugar
    d) Sleeping
    Answer: a
  7. Which is a vaccine-preventable disease?
    a) Smallpox
    b) Cancer
    c) Diabetes
    d) Heart disease
    Answer: a
  8. Vaccines contain:
    a) Live or dead microbes or their components
    b) Chemicals only
    c) Water
    d) Vitamins
    Answer: a
  9. Active immunity develops:
    a) After infection or vaccination
    b) Instantly
    c) By eating healthy food only
    d) By exercise
    Answer: a
  10. Which of the following boosts immunity naturally?
    a) Balanced diet
    b) Smoking
    c) Junk food
    d) Ignoring exercise
    Answer: a

Nutrition and Healthy Lifestyle

  1. A balanced diet includes:
    a) Carbohydrates, proteins, fats, vitamins, minerals
    b) Only carbohydrates
    c) Only proteins
    d) Junk food
    Answer: a
  2. Deficiency of vitamins can lead to:
    a) Scurvy, night blindness, rickets
    b) Diabetes
    c) Malaria
    d) TB
    Answer: a
  3. Proteins help in:
    a) Body growth and repair
    b) Vision only
    c) Immunity only
    d) Mental health only
    Answer: a
  4. Carbohydrates provide:
    a) Energy
    b) Immunity
    c) Growth
    d) None of these
    Answer: a
  5. Fats are required for:
    a) Energy storage and insulation
    b) Immediate energy only
    c) Digestion
    d) Hydration
    Answer: a
  6. Drinking clean water prevents:
    a) Waterborne diseases
    b) Malaria
    c) Viral flu
    d) Genetic disorders
    Answer: a
  7. Overeating junk food can cause:
    a) Obesity and heart disease
    b) Immunity
    c) Improved vision
    d) Bone strength
    Answer: a
  8. Exercise helps to:
    a) Improve circulation and muscle strength
    b) Cause diseases
    c) Reduce immunity
    d) None of the above
    Answer: a
  9. Sleep is important for:
    a) Physical and mental restoration
    b) Only growth
    c) Immunity only
    d) Preventing all diseases
    Answer: a
  10. Which of the following is a healthy habit?
    a) Regular exercise
    b) Smoking
    c) Skipping meals
    d) Junk food
    Answer: a

Hygiene and Disease Prevention

  1. Handwashing with soap removes:
    a) Germs and dirt
    b) Vitamins
    c) Water only
    d) Nutrients
    Answer: a
  2. Covering mouth while sneezing prevents:
    a) Spread of infectious diseases
    b) Heart disease
    c) Diabetes
    d) None of these
    Answer: a
  3. Sanitation refers to:
    a) Clean surroundings and waste management
    b) Eating healthy
    c) Exercise
    d) Sleeping well
    Answer: a
  4. Personal hygiene reduces the risk of:
    a) Infectious diseases
    b) Genetic disorders
    c) Accidents
    d) Aging
    Answer: a
  5. Which habit is harmful to health?
    a) Smoking
    b) Exercising
    c) Eating balanced diet
    d) Bathing regularly
    Answer: a