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Chapter 13 – Why do we Fall Ill?

The following Topics and Sub-Topics are covered in this chapter and are available on MSVgo:


One of the most important facets of a person’s existence is their health. Being unable to carry out usual day-to-day tasks due to a lack of wellbeing or fitness can hinder you from living a normal life.

Why Do We Fall Ill?

We may become ill for a variety of causes, which are described below: 

  • If you live in an area of dirty air, water, or dangerous insects, you can become sick. Malaria and Dengue Fever are two examples. 
  • A lack of basic hygiene often causes diseases. 
  • The state of one’s finances will also play a role in deciding one’s well being. 
  • We can become sick as a result of immune system malfunctions, which may lead to autoimmune diseases. 
  • Physical wellbeing is influenced by mental health. Clinical depression, for example, may result in a lack of appetite and weight loss.

An illness is an irregular condition that affects an individual. There are also psychiatric disorders characterized by a pathological mechanism and a set of symptoms. 

Any illness has a cause. However, some illnesses are impossible to detect due to their perplexing signs. Autoimmune, viral, cancerous, digestive, sexually transmitted, and other disorders are possible. Antibiotics, other drugs, and surgical procedures may all be used to treat them. 

Antibiotics are components that stop bacteria from using their biochemical mechanisms to induce disease. However, these are ineffective against viral infections since viruses depend on the host’s biochemical pathways.

When we feel something is wrong in our organs or organ systems, it could mean that we are ill or have a disorder. Our body’s natural working is disturbed as a result of this. When we have an illness, our bodies send us clues. These are called symptoms. Headache, cold, cough and nausea are some of the typical symptoms. 

There are two groups of diseases: 

  • Acute illnesses 
  • Chronic illnesses

Acute illnesses 

These are those that last for only a limited duration, such as a few days or a few weeks. Chickenpox, typhoid and the common cold are a few examples of acute illness. 

Chronic illnesses 

These are those that last for an extended period, or sometimes for the rest of a person’s life? Cancer and HIV are a few examples.

Diseases may have a variety of immediate causes: 

  • Infectious triggers: These are caused by microbes and can be transmitted from one person to another. 
  • Non-infectious triggers: They aren’t triggered by infectious organisms. Internal imbalances are to blame. Cancer, asthma, elevated blood pressure are examples.

Here are a few suggestions for leading a safe and disease-free life: 

  • Checkups can be done on a regular basis. This aids in the early detection of the condition, making recovery easier. As a result, make sure you have your wellness screenings done regularly. 
  • Smoking affects a person’s life expectancy and quality of life. Quitting this habit will help you live a better life and protect the body from serious infections. 
  • Physical exercise keeps you active. It revitalizes your body and holds you in good shape. 
  • The most significant factor in disease prevention is a well-balanced diet. Consuming nutritious and organic foods holds you in shape and helps you avoid illness. 
  • Obesity is one of the leading causes of high cholesterol and cardiovascular disease. Losing weight will help you avoid the chances of being sick.

When we get ill, we follow a set of procedures to cure the illness. An illness may be treated in one of two ways: 

Reduce the disease’s effects: Medicines are provided to alleviate discomfort or lower the temperature. To put it another way, symptomatic therapy may lessen the severity of a disease, but it may not completely cure it. Since certain illnesses, such as the common cold, do not have a remedy, managing the effects will relieve the pain or infection to some degree. 

Kill the disease: Using antibiotics that can destroy bacteria and kill the disease’s source. Each microbe goes through a unique biochemical life process that aids in its survival. Certain medications that block these biochemical pathways may aid in the killing of the disease-causing microorganism. Antibiotics are useful in this situation.

In this chapter, we learned about the reasons behind falling ill. We learned about different types of diseases. We gathered knowledge on how to treat and prevent diseases.  

1. Why do we fall ill class 9 Ncert? 

Immediate and contributory factors are the two primary causes of illness. The species that invade our bodies and trigger illness are the immediate cause. Viruses, protozoa, and viruses, for example. Contributory causes: These are the reasons that allow these species to invade our bodies—for example, contaminated food or water.

2. Why do we fall ill principles of treatment? 

To lessen the impact of illness, we provide care that alleviates symptoms. For example, we may use pain relievers, anti-inflammatory drugs and bed rest to alleviate fever.

3. What is the major drawback of principles of treatment? 

The only disadvantage of the treatment theory is that treatment can vary where specific signs and symptoms are not present, resulting in a variety of side effects.

4. What is the first principle of treatment? 

The ideals of treatment are to lessen the symptoms, thereby reducing the effects of the disease.

5. What are the principles of the prevention of diseases?

  • Checkups should be done on a regular basis.
  • Physical exercise keeps you active. 
  • Check for obesity. Obesity is one of the leading causes of high cholesterol and cardiovascular diseases.

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High School Physics

  • Alternating Current
  • Atoms
  • Communication Systems
  • Current Electricity
  • Dual nature of Radiation and Matter
  • Electric Charges and Fields
  • Electricity
  • Electromagnetic Induction
  • Electromagnetic Waves
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  • Electrostatic Potential and Capacitance
  • Fluid Pressure
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  • Gravitation
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  • Kinetic Theory
  • Law of motion
  • Light – Reflection And Refraction
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  • Magnetism and Matter
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  • Mechanical properties of Fluids
  • Mechanical properties of Solids
  • Motion
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  • Systems of Particles and Rotational motion
  • Thermal properties of matter
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  • Units and Measurement
  • Vectors, Scalar Quantities and Elementary Calculus
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  • Waves
  • Work, Power and Energy

High School Chemistry

  • Acids, Bases and Salts
  • Alcohols, Phenols and Ethers
  • Aldehydes, Ketones and Carboxylic Acids
  • Aliphatic and Aromatic Hydrocarbons
  • Alkyl and Aryl Halides
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  • Atomic Structure
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  • The d-block and f-block elements
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  • The Solid State
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High School Biology

  • Absorption and Movement of Water in Plants
  • Adolescent Issues
  • Anatomy of Flowering Plants
  • Animal Kingdom
  • Bacteria and Fungi-Friends and Foe
  • Biodiversity and Conservation
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  • Biological Classification
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  • Biotechnology and its Applications
  • Biotic Community
  • Body Fluids and Circulation
  • Breathing and Exchange of Gases
  • Cell – Unit of Life
  • Cell Cycle and Cell Division
  • Cell Division and Structure of Chromosomes
  • Cell Reproduction
  • Cellular Respiration
  • Chemical Coordination and Integration
  • Circulation
  • Control And Coordination
  • Crop Improvement
  • Digestion and Absorption
  • Diversity In Living Organisms
  • Ecosystem
  • Environmental Issues
  • Excretory Products and their Elimination
  • Flowering Plants
  • Genes and Chromosomes
  • Health and Diseases
  • Health and Its Significance
  • Heredity And Evolution
  • Heredity and Variation
  • How Do Organisms Reproduce?
  • Human Diseases
  • Human Eye And Colourful World
  • Human Health and Disease
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  • Improvement In Food Resources
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  • Life Processes
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  • Microbes in Human Welfare
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  • Molecular Basis of Inheritance
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  • Neural Control And Coordination
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  • Organism and Population
  • Photosynthesis
  • Photosynthesis in Higher Plants
  • Plant Growth and Development
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  • Principles of Inheritance and Variation
  • Reproduction and Development in Angiosperms
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  • Strategies for Enhancement in Food Production
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  • The Endocrine System
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  • The Living World
  • The Nervous System and Sense Organs
  • Tissues
  • Transpiration
  • Transport in Plants

High School Math

  • Algebra – Arithmatic Progressions
  • Algebra – Complex Numbers and Quadratic Equations
  • Algebra – Linear Inequalities
  • Algebra – Pair of Linear Equations in Two Variables
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  • Algebra – Principle of Mathematical Induction
  • Algebra – Quadratic Equations
  • Binomial Theorem
  • Calculus – Applications of Derivatives
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  • Probability
  • Sequence and Series
  • Sets and Functions
  • Statistics 
  • Trignometry – Height and Distance
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  • Trignometry – Introduction

Middle School Science

  • Acids, Bases And Salts
  • Air and Its Constituents
  • Basic Biology
  • Body Movements
  • Carbon and Its Compounds
  • Cell – Structure And Functions
  • Changes Around Us
  • Chemical Effects Of Electric Current
  • Chemistry in Your Life
  • Coal And Petroleum
  • Combustion And Flame
  • Components Of Food
  • Conservation Of Plants And Animals
  • Crop Production And Management
  • Electric Current And Its Effects
  • Electricity And Circuits
  • Elements and Compounds
  • Fibre To Fabric
  • Food production and management
  • Force And Pressure
  • Forests: Our Lifeline
  • Friction
  • Fun With Magnets
  • Garbage In, Garbage Out
  • Getting To Know Plants
  • Health and Hygiene
  • Heat
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  • Life Processes: Nutrition in Animals and Plants
  • Light, Shadows And Reflections
  • Materials: Metals And Non-Metals
  • Matter and Its States
  • Metals and Non-metals
  • Micro Organisms: Friend And Foe
  • Motion And Measurement Of Distances
  • Motion And Time
  • Nutrition In Animals
  • Nutrition In Plants
  • Organization in Living Things
  • Our Environment
  • Physical And Chemical Changes
  • Pollution and conservation
  • Pollution Of Air And Water
  • Reaching The Age Of Adolescence
  • Reproduction In Animals
  • Reproduction In Plants
  • Respiration In Organisms
  • Rocks and Minerals
  • Separation Of Substances
  • Simple Machines
  • Soil
  • Some Natural Phenomena
  • Sorting Materials Into Groups
  • Sound
  • Stars And The Solar System
  • Structure of Atom
  • Synthetic Fibers And Plastics
  • The Living Organisms And Their Surroundings
  • Transfer of Heat
  • Transformation of Substances
  • Transportation In Animals And Plants
  • Universe
  • Waste-water Story
  • Water: A Precious Resource
  • Weather, Climate And Adaptations Of Animals To Climate
  • Winds, Storms And Cyclones

Middle School Math

  • Addition
  • Area and Its Boundary
  • Boxes and Sketches
  • Data Handling
  • Fun With Numbers
  • Heavy and Light
  • How Many
  • Long And Short
  • Mapping
  • Measurement
  • Money
  • Multiplication and Factors
  • Multiply and Divide
  • Numbers
  • Parts and Wholes
  • Pattern Recognition
  • Patterns
  • Play With Patterns
  • Rupees And Paise
  • Shapes And Angles
  • Shapes And Designs
  • Shapes and Space
  • Similarity
  • Smart Charts
  • Squares
  • Subtraction
  • Tables And Shares
  • Tenths and Hundredths
  • Time
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