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Chapter 2 – Microorganisms: Friend and Foe

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

Introduction

Microorganisms are microscopic organisms that cannot be seen through naked eyes. You may be tempted into feeling that they are not at all useful, but they are an essential part of your everyday life. Think about the curd that you had for lunch or the cake for dessert; all of that is the action of microorganisms. Now think about the bread that you forgot to put in the fridge and which is longer edible, you must have observed small white things growing on its surface, they are fungus, a type of microorganism. Clearly, microorganisms are friend and foe.

What are microorganisms, and where do they live?

Microorganisms cannot be seen through naked eyes. They may be single-celled like bacteria, algae or protozoa or multicellular like fungi. Where do microorganisms live? Well, practically, on all kinds of surfaces. Bacteria are found to live on surfaces where no other organisms can survive.

The most common phenomena in our daily lives involves microorganisms in the preparation of curd or cake. It requires yeast that is the base of the bakery industry. Microorganisms are also used for commercial large scale production of alcohol, wine and acetic acid. Many fungi and bacteria are used in the preparation of certain antibiotics. They are also used in the control of many diseases. Microbes, interestingly, are also used in the preparation of vaccines that help our body in fighting many diseases. Plants need nitrogen that is only present in the air but cannot be utilised by them as is. Rhizobium bacteria in the roots of the plants helps them convert the nitrogen in the air to a usable form. Microorganisms also play an important part in maintaining the fertility of the soil. They also help in the decomposition of organic matter and thus act as natural cleaners of the environment.

Microorganisms called pathogens can cause diseases in the human body. Some of these pathogens can be passed to other beings through the body of the host and cause communicable diseases. Pathogens carrying animals include mosquitoes and flies. Some disease-causing microorganisms also cause diseases in plants like rice, potato, orange and sugarcane.

There are many methods of food preservation that involve the action of microorganisms. Such methods include preservation by common salt, sugar, oil and vinegar. Methods like boiling are also used in food preservation. The most common activity that you may have observed is the boiling of milk that helps kill microorganisms that cause curdling of the milk. Pasteurisation is the process discovered by Louis Pasteur that is used to prevent the growth of microbes by heating the edible item, like milk and then suddenly cooling it before storing. Dry fruits and vegetables are stored in air-tight packets to prevent them from spoiling due to the action of microbes.

The bacteria called Rhizobium lives in the root nodules of leguminous plants like beans and peas, which help the plant the necessary nitrogen it otherwise cannot get directly from the air.

Nitrogen Cycle

The atmosphere consists of 78% nitrogen gas, but plants cannot directly utilise this. Certain bacteria and algae present in the soil take the nitrogen present in the air and convert it into forms that are usable for plants and animals. These bacteria and algae deliver this nitrogen to plants through the soil itself. Animals get it by consuming the plants in turn. When these plants and animals die, microorganisms work to decompose the organic matter so that the nitrogenous compounds can be used by plants again. As this cycle, called the Nitrogen cycle, goes on, the percentage of nitrogen in the atmosphere remains constant.

1. Are microorganisms friend or foe?

Microorganisms are an integral part of our everyday life. When utilised properly with the knowledge of science, microorganisms can help create not only curd and cake but also vaccines and medications. They also help in food preservation and maintenance of the nitrogen level in the atmosphere.

2. What are friendly microorganisms?

Friendly microorganisms are the ones that do not cause diseases and help in processes of food preservation and nitrogen fixation in the atmosphere. Microorganisms can be converted into friendly ones by utilising them with scientific knowledge.

3. What are the ten uses of microorganisms?

Microorganisms are useful in:

  • Bakery production
  • Dairy production
  • The production of alcoholic beverages
  • The production of vinegar
  • The derivation of enzymes.
  • The production of steroids
  • Insecticides
  • Nitrogen fixation
  • Production of antibiotics
  • Biotechnological research studies

4. Why are microorganisms called foes?

Microorganisms are called foes because they can cause your food to get spoiled. They can also cause many diseases.

5. What are examples of beneficial microorganisms?

The rhizobium bacteria is a beneficial microorganism.

To understand the fine line between microorganisms being friends and foes check out the videos on MSVgo. The clearer your understanding of their behaviour, the better will be your position on determining how to use them effectively in everyday life and when to stay away from them.

Microorganisms are the invisible elves which play a major role in keeping our lives comfortable. But if you do not apply caution you may fall prey to any form of illness caused by them as too much of anything is not good. For instance, the amount of yeast used in bakery is always kept within permissible measurements to keep away from harm’s way. So knowing the fine line between when microorganisms are friends and when foes is crucial.

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
  • Electron Beams and Radioactivity
  • Electrons and Photons
  • Electrostatic Potential and Capacitance
  • Fluid Pressure
  • Force and Acceleration
  • Force And Laws Of Motion
  • Gravitation
  • Internal Energy
  • Kinetic Theory
  • Law of motion
  • Light – Reflection And Refraction
  • Magnetic Effects Of Electric Current
  • Magnetism and Matter
  • Management Of Natural Resources
  • Mechanical properties of Fluids
  • Mechanical properties of Solids
  • Motion
  • Motion in a plane
  • Motion in a straight line
  • Moving Charges and Magnetism
  • Nuclear Energy
  • Nuclei
  • Oscillations
  • Our Environment
  • Paths of Heat
  • Physical world
  • Ray optics and optical instruments
  • Semiconductor Devices
  • Semiconductor Electronics: Materials, Devices and Simple Circuits
  • Simple Machines
  • Sound
  • Sources Of Energy
  • Specific and Latent Heats
  • Spherical Mirrors
  • Static Electricity
  • Systems of Particles and Rotational motion
  • Thermal properties of matter
  • Thermodynamics
  • Units and Measurement
  • Vectors, Scalar Quantities and Elementary Calculus
  • Wave Optics
  • 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
  • Amines
  • Analytical Chemistry 
  • Atomic Structure
  • Atoms And Molecules
  • Basic concepts of Chemistry
  • Biomolecules
  • Carbon And Its Compounds
  • Carboxylic acids and Acid Derivatives
  • Chemical Bonding and Molecular Structures
  • Chemical Energetics
  • Chemical Equilibria
  • Chemical Kinetics
  • Chemical Reactions And Equations
  • Chemical Reactions and Their Mechanisms
  • Chemistry in Everyday Life
  • Chemistry of p-Block elements
  • Chemistry of Transition and Inner Transition
  • Classification of Elements
  • Coordination Compounds
  • Cyanide, Isocyanide, Nitro compounds and Amines
  • Electrochemistry
  • Electrolysis
  • Elements, Compounds and Mixtures
  • Environmental Chemistry
  • Equilibrium
  • Ethers and Carbonyl compounds
  • Haloalkanes and Haloarenes
  • Hydrocarbons
  • Hydrogen
  • Ideal solutions
  • Introduction to Organic Chemistry
  • Ionic equilibria
  • Matter
  • Matter Around Us
  • Matter In Our Surroundings
  • Metallurgy
  • Metals And Non-Metals
  • Mole Concept and Stoichiometry
  • Natural Resources
  • Organic Chemistry – Basic Principles
  • Periodic Classification of Elements
  • Physical and Chemical Changes
  • Physical and Chemical Properties of Water
  • Polymers
  • Preparation, Properties and Uses of Compounds
  • Principles and Processes of Isolation of Elements
  • Redox Reactions
  • Relative Molecular Mass and Mole
  • States of Matter
  • Structure Of The Atom
  • Study of Compounds
  • Study of Gas Laws
  • Study of Representative Elements
  • Surface Chemistry
  • The d-block and f-block elements
  • The Gaseous State
  • The p-Block Elements
  • The Periodic Table
  • The s-Block Elements
  • The Solid State
  • Thermodynamics

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
  • Biofertilizers
  • Biological Classification
  • Biomedical Engineering
  • Biomolecules
  • 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
  • Human Population
  • Human Reproduction
  • Hygiene
  • Improvement In Food Resources
  • Integumentary System- Skin
  • Kingdom Fungi
  • Kingdom Monera
  • Kingdom Protista
  • Life Processes
  • Locomotion and Movement
  • Microbes in Human Welfare
  • Mineral Nutrition
  • Molecular Basis of Inheritance
  • Morphology of Flowering Plants
  • Neural Control And Coordination
  • Nutrition in Human Beings
  • Organism and Population
  • Photosynthesis
  • Photosynthesis in Higher Plants
  • Plant Growth and Development
  • Plant Kingdom
  • Pollination and Fertilization
  • Pollution; Sources and its effects
  • Principles of Inheritance and Variation
  • Reproduction and Development in Angiosperms
  • Reproduction in Organisms
  • Reproductive Health
  • Respiration in Human Beings
  • Respiration in Plants
  • Respiratory System
  • Sexual Reproduction in Flowering Plants
  • Strategies for Enhancement in Food Production
  • Structural Organisation in Animals
  • Structural Organisation of the Cell
  • The Endocrine System
  • The Fundamental Unit Of Life
  • 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
  • Algebra – Polynomials
  • Algebra – Principle of Mathematical Induction
  • Algebra – Quadratic Equations
  • Binomial Theorem
  • Calculus – Applications of Derivatives
  • Calculus – Applications of the Integrals
  • Calculus – Continuity and Differentiability
  • Calculus – Differential Equations
  • Calculus – Integrals
  • Geometry – Area
  • Geometry – Circles
  • Geometry – Conic Sections
  • Geometry – Constructions
  • Geometry – Introduction to Euclid’s Geometry
  • Geometry – Three-dimensional Geometry
  • Geometry – Lines and Angles
  • Geometry – Quadrilaterals
  • Geometry – Straight Lines
  • Geometry – Triangles
  • Linear Programming
  • Matrices and Determinants
  • Mensuration – Areas
  • Mensuration – Surface Areas and Volumes
  • Number Systems
  • Number Systems – Real Numbers
  • Permutations and Combinations
  • Probability
  • Sequence and Series
  • Sets and Functions
  • Statistics 
  • Trignometry – Height and Distance
  • Trignometry – Identities
  • 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
  • Hydrogen
  • 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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