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Rapid Revision: The Ultimate Treasure

Meaning of Health

Health is not just the absence of disease. It is a state of complete physical, mental, and social well-being. A healthy person feels physically fit, mentally stable, and socially connected.

Health involves three interconnected aspects:

  • Physical well-being - proper functioning of the body
  • Mental well-being - positive thoughts and emotional balance
  • Social well-being - healthy relationships and ability to interact with others

Traditional knowledge systems also emphasize balance between body, mind, and surroundings through proper routine, diet, exercise, rest, and a calm mind.Aspects of healthAspects of health

How to Stay Healthy

Good health depends largely on lifestyle and environment. Healthy habits support both the body and mind.

Healthy lifestyle practices include:

  • Eating a balanced diet rich in fruits, vegetables, and whole grains
  • Avoiding excessive sugary, fatty, or processed foods
  • Staying physically active through sports, walking, cycling, or exercise
  • Limiting screen time and spending time outdoors
  • Getting adequate sleep
  • Practising yoga or breathing exercises
  • Avoiding harmful substances such as tobacco, alcohol, and drugs

Unhealthy habits such as junk food consumption, lack of sleep, skipping meals, and excessive screen use can negatively affect health.

Importance of a Clean Environment

Clean surroundings are essential for maintaining health. Polluted and unhygienic environments increase the risk of infections and respiratory problems.

Important environmental factors affecting health:

  • Clean air and safe drinking water
  • Proper sanitation and waste disposal
  • Control of flies, mosquitoes, and other disease carriers
  • Reduced pollution

Mental health is also influenced by social interaction. Spending time with family and friends supports emotional well-being.

How We Know We Are Unwell

When the body does not function normally, we experience illness.

Two important indicators of illness are:

  • Symptoms - what the person feels (pain, tiredness, dizziness)
  • Signs - what can be observed or measured (fever, rash, swelling, high blood pressure)

Doctors use both symptoms and signs to diagnose diseases.

Diseases: Causes and Types

A disease is a condition that disrupts the normal functioning of the body or mind. Diseases may be caused by pathogens, poor nutrition, unhealthy lifestyle, or environmental factors.

Diseases are broadly classified into two main types.

Types of Diseases

Types of Diseases

Communicable Diseases

Communicable diseases are caused by pathogens such as bacteria, viruses, fungi, protozoa, or worms. These diseases can spread between individuals.

Common modes of transmission:

  • Air (coughing, sneezing)
  • Direct contact with infected person
  • Indirect contact through contaminated objects
  • Contaminated food or water
  • Insect vectors such as mosquitoes and flies
  • Animal bites

Examples include common cold, measles, tuberculosis, cholera, typhoid, malaria, and dengue.Common methods of transmission of diseasesCommon methods of transmission of diseases

Prevention of Communicable Diseases

Simple preventive measures can significantly reduce the spread of infections:

  • Maintaining personal hygiene
  • Washing hands regularly with soap
  • Covering mouth and nose while coughing or sneezing
  • Drinking clean and safe water
  • Eating properly cooked food
  • Avoiding sharing personal items
  • Using mosquito nets and repellents
  • Keeping surroundings clean
  • Staying at home when ill
  • Vaccination

Isolation of infected individuals also helps prevent transmission.

Non-Communicable Diseases

Non-communicable diseases (NCDs) are not caused by pathogens and do not spread from person to person. They are mainly associated with lifestyle, diet, environment, or genetic factors.

Examples include:

  • Diabetes
  • Cancer
  • Asthma
  • Heart disease
  • Obesity
  • High blood pressure

Some NCDs caused by lack of nutrients are called deficiency diseases (for example, scurvy, anaemia, goitre).

Many NCDs are chronic, meaning they last for a long time and require continuous care.

Immunity and the Immune System

  • Immunity is the body's natural ability to fight disease-causing organisms. The immune system protects the body by recognizing and destroying harmful pathogens.
  • People with stronger immunity tend to fall sick less often than those with weaker immunity.

Vaccination

Vaccines help prevent infectious diseases by preparing the immune system to recognize specific pathogens.

Important features of vaccines:

  • Made from weakened or dead pathogens or their harmless parts

  • Provide acquired immunity

  • Prevent disease before infection occurs

  • Protect both individuals and communities

Vaccination has helped control or eliminate many serious diseases worldwide.

Treatment of Diseases

If the immune system cannot fight an infection, medical treatment is required.

Antibiotics

Antibiotics are medicines used to treat bacterial infections. They work by killing bacteria or preventing their growth.

Key points:

  • Effective only against bacteria
  • Do not work against viral infections such as cold or flu
  • Should be taken only under medical supervision

Antibiotic Resistance

Misuse or overuse of antibiotics can lead to antibiotic resistance. In this condition, bacteria survive despite treatment and continue to multiply.

Resistance develops due to:

  • Taking antibiotics when not needed
  • Not completing the full course of treatment
  • Overuse in humans or animals
  • Spread of resistant bacteria in communities

To prevent antibiotic resistance:

  • Use antibiotics only when prescribed by a doctor
  • Follow the correct dosage and duration
  • Avoid self-medication

Traditional and Supportive Treatments

Traditional medical systems use natural substances and lifestyle practices to maintain health and manage some illnesses. While helpful for overall well-being, they may not cure all diseases.

Management of long-term diseases often includes:

  • Medicines
  • Lifestyle changes
  • Regular monitoring
  • Rehabilitation

Early diagnosis improves treatment outcomes.

The document Rapid Revision: The Ultimate Treasure is a part of the Class 8 Course Science Curiosity Class 8 - New NCERT.
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FAQs on Rapid Revision: The Ultimate Treasure

1. What is the definition of health?
Ans. Health is defined as a state of complete physical, mental, and social well-being, rather than merely the absence of disease or infirmity. It encompasses various aspects, including physical fitness, mental resilience, and social interactions.
2. What are some habits that contribute to staying healthy?
Ans. Staying healthy involves adopting several habits such as maintaining a balanced diet, engaging in regular physical activity, ensuring adequate sleep, managing stress effectively, and avoiding harmful behaviours like smoking and excessive alcohol consumption.
3. How do diseases transmit from one person to another?
Ans. Diseases can be transmitted through various means including direct contact with an infected person, airborne particles, contaminated surfaces, or through vectors such as insects. Understanding these modes of transmission is crucial for prevention.
4. What role do vaccines play in immunity?
Ans. Vaccines stimulate the immune system to recognise and combat pathogens by introducing a harmless component of the pathogen. This prepares the body to respond more effectively if exposed to the actual disease in the future, thereby enhancing immunity.
5. What are some key points in managing health at the community level?
Ans. Key points in community health management include promoting health education, ensuring access to healthcare services, implementing vaccination programmes, encouraging healthy lifestyle choices, and fostering community engagement to address health-related issues collectively.
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