CBSE Class 10 Science Important Question and Answers of all chapters

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CBSE Class 10 Science Important question and answers

Chapter-wise Class 10 Science Question and answers for Chemistry, Biology, and Physics with clear concepts, important definitions, diagrams, formulas, and exam-focused preparation.

Chemistry

Chemical reactions, acids-bases, metals, non-metals, and carbon compounds.

⚗️

Chemical Reactions and Equations

Balancing equations, reaction types, oxidation, reduction, and chemical changes.

🧪

Acids, Bases and Salts

pH scale, indicators, neutralisation, salts, and important chemical properties.

🔩

Metals and Non-metals

Properties, reactions, reactivity series, extraction, corrosion, and metallurgy.

🧬

Carbon and its Compounds

Covalent bonding, homologous series, functional groups, nomenclature, and reactions.

Biology

Life processes, coordination, reproduction, heredity, evolution, and environment.

🫀

Life Processes

Nutrition, respiration, transportation, excretion, and important biological processes.

🧠

Control and Coordination

Nervous system, reflex arc, brain, hormones, and plant coordination.

🌱

Reproduction

Asexual reproduction, sexual reproduction, reproductive organs, and life continuity.

🧬

Heredity and Evolution

Inheritance, Mendel’s laws, traits, sex determination, variation, and evolution.

🌍

Our Environment

Ecosystem, food chains, food webs, ozone layer, waste, and environmental balance.

Physics

Light, human eye, electricity, magnetism, circuits, and electromagnetic effects.

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Light: Reflection and Refraction

Mirrors, lenses, ray diagrams, image formation, mirror formula, and lens formula.

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Human Eye and Colourful World

Eye defects, correction, prism, dispersion, scattering, and atmospheric refraction.

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Electricity

Ohm’s law, resistance, circuits, heating effect, electric power, and numericals.

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Magnetic Effects of Electric Current

Magnetic field, field lines, motor effect, electromagnetic induction, and safety devices.

Class 8 Science Chapter 2 The Invisible Living World Beyond Our Naked Eye Questions and Answers

Delhi Public School Notes

Class 8 Science Questions and Answers: The Invisible Living World Beyond Our Naked Eye

Class 8 Science The Invisible Living World Beyond Our Naked Eye Questions and Answers | CBSE Important Questions

Meta Description: Get CBSE Class 8 Science important questions and answers for The Invisible Living World: Beyond Our Naked Eye. Includes very short answers, short answers, long answers, MCQs, assertion-reason, competency-based questions, diagram questions, HOTS and quick revision points.

This premium question-answer set is designed for CBSE Class 8 Science students preparing for school exams, unit tests and quick revision. The questions are based on the chapter The Invisible Living World: Beyond Our Naked Eye and cover cells, microscopes, microorganisms, microbes in food, decomposition, microalgae, fermentation and the basic unit of life.

Class 8 Science Questions and Answers CBSE Class 8 Science Important Questions NCERT Science Chapter Questions Competency Based Science Questions

Chapter Overview

Particular	Details
Class	Class 8
Board	CBSE
Subject	Science
Chapter	The Invisible Living World: Beyond Our Naked Eye
Main Concepts	Microscope, cell, plant cell, animal cell, microorganisms, fungi, bacteria, protozoa, algae, viruses, decomposition, fermentation, curd formation, biogas, Rhizobium, microalgae

Table of Contents

• Very Short Answer Questions
• Short Answer Questions
• Long Answer Questions
• MCQs
• Assertion and Reason Questions
• Case Study Questions
• Diagram-Based Questions
• HOTS Questions
• Quick Revision Points
• Final Exam Tips

Very Short Answer Questions

Question 1.

What is the basic unit of life?

Answer:

The cell is the basic unit of life.

Question 2.

What are microorganisms?

Answer:

Microorganisms are tiny living organisms that cannot be seen with the naked eye.

Question 3.

Name the scientist who first used the word cell in science.

Answer:

Robert Hooke first used the word cell in science.

Question 4.

Who is known as the Father of Microbiology?

Answer:

Antonie van Leeuwenhoek is known as the Father of Microbiology.

Question 5.

Name the outer layer of a typical cell.

Answer:

The outer layer of a typical cell is the cell membrane.

Question 6.

Which part of the cell regulates cell activities and growth?

Answer:

The nucleus regulates cell activities and growth.

Question 7.

Which cell part provides rigidity and strength to plant cells?

Answer:

The cell wall provides rigidity and strength to plant cells.

Question 8.

Name the green pigment present in chloroplasts.

Answer:

The green pigment is chlorophyll.

Question 9.

Name one unicellular fungus mentioned in the chapter.

Answer:

Yeast is a unicellular fungus.

Question 10.

Name the bacterium that helps in curd formation.

Answer:

Lactobacillus helps in curd formation.

Question 11.

What is decomposition?

Answer:

Decomposition is the breakdown of complex substances of dead plants and animals into simpler nutrient-rich substances by microorganisms.

Question 12.

Name the bacteria found in root nodules of legumes.

Answer:

Rhizobium bacteria are found in root nodules of legumes.

Short Answer Questions

Question 1.

Why was the invention of the microscope important?

Answer:

The invention of the microscope was important because it helped humans see tiny living organisms and cell structures that cannot be seen with the naked eye. It opened a hidden world of microorganisms and cells.

Question 2.

Why did the letters appear larger when seen through a round-bottom flask filled with water?

Answer:

The flask filled with water acted like a magnifying glass. A curved transparent surface can make small objects appear larger, just like a lens.

Question 3.

Write the three basic parts of a typical cell.

Answer:

The three basic parts of a typical cell are cell membrane, cytoplasm and nucleus.

Question 4.

How is an onion peel cell different from a human cheek cell?

Answer:

Onion peel cells are nearly rectangular and closely arranged. They have a cell wall in addition to the cell membrane. Human cheek cells are polygon-shaped, thin and flat, and they do not have a cell wall.

Question 5.

What is the function of the cell membrane?

Answer:

The cell membrane encloses the cytoplasm and nucleus, separates one cell from another, and allows the entry of useful materials and exit of waste materials.

Question 6.

Why do nerve cells have a long and branched structure?

Answer:

Nerve cells, also called neurons, carry messages in the body. Their elongated and branched structure helps them reach different parts of the body and pass messages quickly.

Question 7.

Write the correct sequence of levels of organisation in a living organism.

Answer:

The correct sequence is: Cell → Tissue → Organ → Organ system → Organism.

Question 8.

Why are plants and animals called multicellular organisms?

Answer:

Plants and animals are called multicellular organisms because their bodies are made up of many cells. These cells perform specialised functions and cooperate with each other.

Question 9.

Why do pickles and murabbas not get infected easily by microorganisms?

Answer:

Pickles and murabbas contain high concentrations of salt or sugar. These act as preservatives and do not allow microorganisms to grow easily.

Question 10.

How does yeast make dough soft and fluffy?

Answer:

Yeast respires and breaks down food to release energy. During this process, carbon dioxide is released. The carbon dioxide forms bubbles in the dough, making it soft and fluffy.

Long Answer Questions

Question 1.

Describe the structure and functions of the main parts of a cell.

Answer:

A typical cell has three main parts: cell membrane, cytoplasm and nucleus.

• Cell membrane: It encloses the cytoplasm and nucleus. It separates one cell from another and allows useful materials to enter and wastes to leave.
• Cytoplasm: It is the space between the cell membrane and nucleus. It contains cell components and substances such as carbohydrates, proteins, fats and mineral salts. Most life processes occur in the cytoplasm.
• Nucleus: It regulates all activities inside the cell and also controls growth.
• Cell wall: Plant cells have an extra outer layer called the cell wall. It provides rigidity and strength to the cell.

Question 2.

Explain how microorganisms help in cleaning the environment.

Answer:

Microorganisms such as bacteria and fungi act on plant and animal waste and break it down into simpler substances. This process is called decomposition.

• They decompose fallen leaves, fruit peels, vegetable peels and dead organisms.
• The waste changes into dark, nutrient-rich manure.
• The nutrients return to the soil and help plants grow better.
• Thus, microorganisms recycle waste and clean the environment naturally.

Question 3.

Explain the role of microorganisms in food preparation.

Answer:

Microorganisms are very useful in food preparation.

• Yeast is used to make breads, cakes and similar food items soft and fluffy.
• Yeast releases carbon dioxide during respiration, which forms bubbles in dough.
• Some bacteria help in the fermentation of batter for idli and dosa and dough for bhatura.
• Lactobacillus converts milk into curd by fermenting lactose and producing lactic acid.
• These processes improve texture, taste and usefulness of food.

Question 4.

Why is the cell considered the basic unit of life?

Answer:

The cell is considered the basic unit of life because the body of every living organism is made up of cells. A cell contains different components that help an organism perform life functions and survive. Unicellular organisms carry out all life processes within a single cell. In multicellular organisms, different cells perform specialised functions and work together. Therefore, the cell is the smallest living unit that can perform essential life processes.

Question 5.

Describe the importance of microalgae.

Answer:

Microalgae are microscopic plant-like organisms found in water, soil, air and even on trees. They are important because:

• They make their own food using sunlight.
• They release oxygen and produce more than half of the Earth’s oxygen supply.
• They are rich in nutrients and serve as food for aquatic animals.
• Some microalgae such as Spirulina, Chlorella and Diatoms are used as health supplements and medicines.
• They help in cleaning water and can be used to make biofuel.

MCQs

Question 1.

Which device is used to observe microorganisms?

• A. Telescope
• B. Microscope
• C. Periscope
• D. Stethoscope

Correct Answer: B. Microscope

Explanation: A microscope magnifies tiny organisms and makes them visible.

Question 2.

Robert Hooke observed a thin slice of which material?

• A. Cork
• B. Leaf
• C. Cheek cell
• D. Soil

Correct Answer: A. Cork

Explanation: Robert Hooke observed a thin slice of cork and called the small spaces cells.

Question 3.

Which of the following is present in plant cells but not in human cheek cells?

• A. Cytoplasm
• B. Cell membrane
• C. Nucleus
• D. Cell wall

Correct Answer: D. Cell wall

Explanation: Onion peel cells have a cell wall, while human cheek cells do not.

Question 4.

Which microorganism helps in making curd?

• A. Rhizobium
• B. Lactobacillus
• C. Amoeba
• D. Paramecium

Correct Answer: B. Lactobacillus

Explanation: Lactobacillus ferments lactose in milk and forms curd.

Question 5.

Yeast belongs to which group of microorganisms?

• A. Fungi
• B. Protozoa
• C. Algae
• D. Virus

Correct Answer: A. Fungi

Explanation: Yeast is a microorganism that belongs to fungi.

Question 6.

Which gas makes dough soft and fluffy?

• A. Oxygen
• B. Nitrogen
• C. Carbon dioxide
• D. Hydrogen

Correct Answer: C. Carbon dioxide

Explanation: Yeast releases carbon dioxide, which forms bubbles in the dough.

Question 7.

Which bacteria live in root nodules of legumes?

• A. Lactobacillus
• B. Rhizobium
• C. Amoeba
• D. Yeast

Correct Answer: B. Rhizobium

Explanation: Rhizobium traps nitrogen from air and helps plants grow better.

Question 8.

Which structure is found in bacteria instead of a well-defined nucleus?

• A. Chloroplast
• B. Nucleoid
• C. Vacuole
• D. Cell wall only

Correct Answer: B. Nucleoid

Explanation: Bacteria do not have a well-defined nucleus. They have a nucleoid region.

Question 9.

Which of the following can reproduce only inside a host organism?

• A. Virus
• B. Yeast
• C. Algae
• D. Amoeba

Correct Answer: A. Virus

Explanation: Viruses multiply only after entering a living cell.

Question 10.

Which of the following is a microalga called a superfood?

• A. Spirulina
• B. Bread mould
• C. Rhizobium
• D. Paramecium

Correct Answer: A. Spirulina

Explanation: Spirulina is rich in protein and vitamin B12 and is known for health benefits.

Assertion and Reason Questions

Question 1.

Assertion: A microscope helps us observe microorganisms.
Reason: Microorganisms are too small to be seen with the naked eye.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: Microorganisms need magnification for observation because they are invisible to the unaided eye.

Question 2.

Assertion: Plant cells have a cell wall.
Reason: The cell wall provides rigidity and strength to plant cells.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: The cell wall helps plant cells remain firm and compactly arranged.

Question 3.

Assertion: Yeast is used in making bread and cakes.
Reason: Yeast releases carbon dioxide during respiration.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: Carbon dioxide bubbles make dough soft and fluffy.

Question 4.

Assertion: Bacteria have a well-defined nucleus.
Reason: Bacteria have a nucleoid region instead of a well-defined nucleus.

Correct Option: Assertion is false, but Reason is true.

Explanation: Bacteria lack a well-defined nucleus and nuclear membrane.

Question 5.

Assertion: Microorganisms are always harmful.
Reason: Some microorganisms help in decomposition, curd formation and fermentation.

Correct Option: Assertion is false, but Reason is true.

Explanation: Microorganisms can be beneficial or harmful. Many are useful in food preparation and environmental cleaning.

Case Study / Competency-Based Questions

Case Study 1: Yeast and Dough

A student took two bowls, A and B. In both bowls, she added flour, sugar and warm water. In bowl A, she added yeast. In bowl B, she did not add yeast. After keeping both bowls in a warm place for a few hours, the dough in bowl A became fluffy and had a different smell.

Question 1. Which microorganism was added to bowl A?

Answer:

Yeast was added to bowl A.

Question 2. Why did the dough in bowl A rise?

Answer:

Yeast released carbon dioxide during respiration. The gas formed bubbles and made the dough rise.

Question 3. Why was warm water used?

Answer:

Yeast grows well in warm conditions, so warm water helps yeast activity.

Question 4. Why did bowl B not show the same change?

Answer:

Bowl B did not contain yeast, so carbon dioxide was not produced in the same way.

Question 5. Name two food items made using this property of yeast.

Answer:

Bread and cakes are made using this property of yeast.

Case Study 2: Manure Formation

A student added fruit and vegetable peels into a container half-filled with garden soil. She covered the waste with another layer of soil and left it for 2-3 weeks. After this period, the waste turned into a dark-coloured material rich in nutrients.

Question 1. What is the dark-coloured material called?

Answer:

It is called manure.

Question 2. Which microorganisms help in this process?

Answer:

Bacteria and fungi help in this process.

Question 3. What is the process of breaking down waste called?

Answer:

It is called decomposition.

Question 4. How does manure help plants?

Answer:

Manure adds nutrients to the soil and increases soil fertility.

Question 5. What conditions help manure formation?

Answer:

Optimal temperature and appropriate moisture level help manure formation.

Diagram-Based Questions

Question 1.

In a diagram of onion peel cells, which parts should be labelled?

Answer:

The important labels are cell wall, cell membrane, cytoplasm and nucleus.

Question 2.

In a human cheek cell diagram, name the three main parts visible.

Answer:

The visible parts are cell membrane, cytoplasm and nucleus.

Question 3.

What is the main difference between the labelled diagrams of plant cell and animal cell?

Answer:

A plant cell has a cell wall, chloroplasts and a large vacuole. An animal cell does not have a cell wall or chloroplasts, and vacuoles are usually absent or small.

Question 4.

In a bacterial cell diagram, what is the nucleoid?

Answer:

The nucleoid is the region in a bacterial cell that contains genetic material. Bacteria do not have a well-defined nucleus.

Question 5.

In the experimental set-up of yeast with sugar solution and lime water, what change is expected in lime water?

Answer:

Lime water turns milky because yeast produces carbon dioxide, which reacts with lime water.

HOTS / Application-Based Questions

Question 1.

What would happen if microorganisms did not exist on Earth?

Answer:

Dead plants, animals and waste materials would not decompose properly. Nutrients would not return to the soil, natural manure formation would stop, and the environment would become filled with waste.

Question 2.

Why do farmers grow legumes such as beans, peas and lentils in rotation with other crops?

Answer:

Legumes have root nodules containing Rhizobium bacteria. These bacteria trap nitrogen from air and make it useful for plants, naturally increasing soil fertility for the next crop.

Question 3.

Why does curd form faster in warm milk than in cold milk?

Answer:

Lactobacillus bacteria grow well in warm conditions. In warm milk, they multiply and ferment lactose faster, producing lactic acid and forming curd.

Question 4.

Why is the shape of a cell related to its function? Explain with two examples.

Answer:

Cell shape helps a cell perform its function efficiently. Nerve cells are long and branched, so they can carry messages quickly to different body parts. Muscle cells are spindle-shaped, thin and flexible, so they can contract and relax to produce movement.

Question 5.

Why should microalgae be conserved?

Answer:

Microalgae produce a large amount of Earth’s oxygen, serve as food for aquatic animals, help clean water, and are useful as health supplements, medicines and biofuel sources. Their conservation helps maintain environmental balance.

Quick Revision Points

1. The cell is the basic unit of life.

2. Robert Hooke used the word cell after observing cork.

3. Antonie van Leeuwenhoek is called the Father of Microbiology.

4. Cell organisation: Cell → Tissue → Organ → Organ system → Organism.

5. A typical cell has cell membrane, cytoplasm and nucleus.

6. Plant cells have a cell wall, chloroplasts and a large vacuole.

7. Microorganisms include bacteria, fungi, protozoa and algae.

8. Viruses multiply only inside a living host cell.

9. Yeast makes dough fluffy by releasing carbon dioxide.

10. Lactobacillus helps in curd formation.

11. Rhizobium lives in root nodules of legumes.

12. Microalgae produce oxygen and help maintain oxygen balance on Earth.

Final Exam Tips

• Revise the difference between plant cell, animal cell and bacterial cell.
• Learn the functions of cell membrane, cytoplasm, nucleus, cell wall, vacuole and chloroplast.
• Practise diagrams of onion peel cell, human cheek cell, plant cell, animal cell and bacterial cell.
• Prepare examples of useful microorganisms: yeast, Lactobacillus, Rhizobium and microalgae.
• For competency-based questions, focus on experiments related to yeast fermentation, curd formation and manure formation.

Conclusion

The chapter The Invisible Living World: Beyond Our Naked Eye helps students understand that many living organisms and cell structures are too small to be seen without a microscope. It explains cells as the basic units of life, the difference between plant, animal and bacterial cells, and the useful role of microorganisms in food, agriculture, decomposition, biogas and oxygen production. These CBSE Class 8 Science Important Questions are useful for quick revision, school exams and concept-based preparation.

Additional Very Short Answer Questions

Question 13.

What is a lens?

Answer:

A lens is a curved piece of glass that can make small things appear bigger.

Question 14.

Why was a lens named so?

Answer:

It was named lens because it was shaped like a lentil seed, thick in the middle and thin at the edge.

Question 15.

Name the book published by Robert Hooke in 1665.

Answer:

Robert Hooke published a book called Micrographia.

Question 16.

What did Robert Hooke observe in a thin slice of cork?

Answer:

He observed many small empty spaces that looked like a honeycomb.

Question 17.

What are cheek cells?

Answer:

Cheek cells are polygon-shaped cells that form the inner lining of the mouth.

Question 18.

Which stain is used to observe onion peel cells?

Answer:

Safranin is used to stain onion peel cells.

Question 19.

Which stain is used to observe human cheek cells?

Answer:

Methylene blue is used to stain human cheek cells.

Question 20.

What is the function of glycerin while preparing a slide?

Answer:

Glycerin prevents the cells from drying and improves clarity during observation.

Question 21.

What are plastids?

Answer:

Plastids are tiny rod-shaped structures present in plant cells.

Question 22.

Name the plastids that contain chlorophyll.

Answer:

Chloroplasts contain chlorophyll.

Question 23.

What is the largest known cell in the living world?

Answer:

The yolk of an ostrich egg is the largest known cell in the living world.

Question 24.

What are microbes?

Answer:

Microbes are very small living beings that cannot be seen with the naked eye.

Additional Short Answer Questions

Question 11.

Why are stains used while observing cells under a microscope?

Answer:

Stains are used to improve the visibility of cells under the microscope. They increase contrast and make cell parts such as the nucleus easier to observe.

Question 12.

Why should no air bubbles be trapped while placing a coverslip?

Answer:

Air bubbles can disturb the clear view of the specimen. They may hide cell parts and make microscopic observation difficult.

Question 13.

Why are onion peel cells compared with bricks in a wall?

Answer:

Onion peel cells are closely arranged without much space, just like bricks in a wall. This shows how cells form a compact structure in plants.

Question 14.

How do vacuoles help plant cells?

Answer:

Vacuoles help plant cells store important substances, remove waste and maintain the shape of the cell. They also provide strength and support to the plant.

Question 15.

How are vacuoles different in plant and animal cells?

Answer:

Plant cells usually have a large vacuole. In animal cells, vacuoles are usually absent, and if present, they are small.

Question 16.

Why are muscle cells suitable for movement?

Answer:

Muscle cells are thin, flexible and spindle-shaped. These features help them contract and relax, making movement possible.

Question 17.

How do muscle cells help in digestion?

Answer:

Muscle cells in the food pipe contract and relax in a wave-like manner to push food down to the stomach. Muscle cells in the stomach wall help churn the food.

Question 18.

Why are microorganisms found in pond water and soil suspension?

Answer:

Microorganisms are present all around us, including water and soil. Pond water and soil suspension contain tiny living organisms that can be observed only with a microscope.

Question 19.

Why do fruits sometimes show cotton-like or powdery growth?

Answer:

Fruits may show cotton-like or powdery growth because they get infected by microbes present in air, water, soil or surrounding surfaces.

Question 20.

Why is a foldable paper microscope useful?

Answer:

A foldable paper microscope is low-cost and makes the microscopic world accessible to many people, though it may not show as much detail as a high-powered laboratory microscope.

Additional Long Answer Questions

Question 6.

Explain the contribution of Robert Hooke and Antonie van Leeuwenhoek in the discovery of the microscopic world.

Answer:

Robert Hooke and Antonie van Leeuwenhoek played important roles in revealing the microscopic world.

• In 1665, Robert Hooke published a book called Micrographia.
• He used a microscope to observe tiny objects and made detailed drawings of them.
• He observed a thin slice of cork and saw many small empty compartments.
• These compartments reminded him of a honeycomb, and he called them cells.
• Antonie van Leeuwenhoek made better lenses and more useful microscopes.
• He was the first person to clearly see and describe tiny living things such as bacteria and blood cells.
• He is known as the Father of Microbiology.

Question 7.

Describe the procedure to prepare and observe an onion peel slide.

Answer:

• Take an onion bulb and wash it properly.
• Cut the onion vertically into pieces.
• Pull out a thin transparent layer from the inner surface using forceps. This is called the onion peel.
• Place the peel in a petri dish containing safranin for about 30 seconds.
• Transfer the peel to water to remove extra stain.
• Place the stained peel carefully on a clean glass slide.
• Add a drop of glycerin to prevent drying.
• Place a coverslip gently using a needle so that no air bubbles are trapped.
• Remove extra glycerin with blotting paper.
• Observe the slide under a microscope.

Nearly rectangular, closely arranged cells are observed.

Question 8.

Explain the differences between plant cells and animal cells.

Answer:

Plant Cell	Animal Cell
Plant cells have a cell wall.	Animal cells do not have a cell wall.
Plant cells have chloroplasts in green parts.	Animal cells do not have chloroplasts.
Plant cells usually have a large vacuole.	Animal cells usually have no vacuole, or small vacuoles if present.
Plant cells are often more firm due to the cell wall.	Animal cells are generally more flexible in shape.

Question 9.

Explain the structure and importance of bacterial cells.

Answer:

Bacteria are microorganisms that may be spherical, comma-shaped, spiral-shaped or rod-shaped. They have a cellular structure but do not have a well-defined nucleus. Instead, they contain a nucleoid region. Some bacteria have one long hair-like structure and many small hair-like projections around the cell.

Bacteria are important because some of them help in digestion, curd formation, decomposition and increasing soil fertility. For example, Lactobacillus helps in curd formation and Rhizobium helps legumes by trapping nitrogen from air.

Question 10.

Explain how microorganisms are both useful and harmful.

Answer:

Microorganisms can be both useful and harmful.

• Useful roles: Some microbes decompose plant and animal waste and clean the environment.
• Some microorganisms help in making manure by breaking down fruit and vegetable peels.
• Yeast helps in making bread, cakes and other fermented foods soft and fluffy.
• Lactobacillus helps convert milk into curd.
• Rhizobium helps increase soil fertility by trapping nitrogen.
• Microalgae release oxygen, provide food for aquatic animals and help clean water.
• Harmful roles: Some microbes infect food and cause it to rot. Viruses may infect plants, animals or bacteria and may cause disease.

Additional MCQs

Question 11.

Which stain is used for onion peel cells?

• A. Methylene blue
• B. Safranin
• C. Iodine vapour
• D. Lime water

Correct Answer: B. Safranin

Explanation: Safranin gives a pinkish colour to onion peel cells and makes them easier to observe.

Question 12.

Which stain is used for human cheek cells?

• A. Safranin
• B. Methylene blue
• C. Glycerin
• D. Sugar solution

Correct Answer: B. Methylene blue

Explanation: Methylene blue increases contrast and helps in observing cheek cells clearly.

Question 13.

Which cell part controls all activities inside the cell?

• A. Cell wall
• B. Cytoplasm
• C. Nucleus
• D. Vacuole

Correct Answer: C. Nucleus

Explanation: The nucleus regulates all activities that occur within the cell and also regulates growth.

Question 14.

Which of the following is the correct order of organisation in living organisms?

• A. Tissue → Cell → Organ → Organism
• B. Cell → Tissue → Organ → Organ system → Organism
• C. Organism → Organ → Cell → Tissue
• D. Organ → Tissue → Cell → Organ system

Correct Answer: B. Cell → Tissue → Organ → Organ system → Organism

Explanation: Cells form tissues, tissues form organs, organs form organ systems and organ systems form an organism.

Question 15.

Which cells form a protective lining on the inner surface of the cheek?

• A. Nerve cells
• B. Muscle cells
• C. Cheek cells
• D. Root cells

Correct Answer: C. Cheek cells

Explanation: Inner cheek cells are thin and flat and form a protective lining.

Question 16.

Which cells carry messages in the body?

• A. Nerve cells
• B. Onion peel cells
• C. Bread mould cells
• D. Root nodule cells

Correct Answer: A. Nerve cells

Explanation: Nerve cells, also called neurons, carry messages in the body.

Question 17.

Which of the following is observed in pond water?

• A. Amoeba
• B. Paramecium
• C. Algae
• D. All of these

Correct Answer: D. All of these

Explanation: Amoeba, Paramecium and algae may be observed in pond water.

Question 18.

Which microorganism is described as single-celled, moving and irregular in shape?

• A. Amoeba
• B. Bread mould
• C. Rhizobium
• D. Spirulina

Correct Answer: A. Amoeba

Explanation: Amoeba is a unicellular protozoan with an irregular shape.

Question 19.

Which microorganism is described as branched filament without chlorophyll?

• A. Algae
• B. Fungi
• C. Bacteria
• D. Paramecium

Correct Answer: B. Fungi

Explanation: Bread mould and mould are fungi with branched filaments and without chlorophyll.

Question 20.

Which of the following conditions helps curd formation?

• A. Very cold conditions
• B. Warm conditions
• C. Complete dryness
• D. Absence of bacteria

Correct Answer: B. Warm conditions

Explanation: Lactobacillus grows well in warm conditions and helps milk turn into curd.

Additional Assertion and Reason Questions

Question 6.

Assertion: Safranin is used while preparing an onion peel slide.
Reason: Safranin stains the cells and helps us see them clearly.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: Safranin gives colour to onion peel cells, improving visibility under the microscope.

Question 7.

Assertion: Nerve cells are long and branched.
Reason: Their shape helps them carry messages to different parts of the body quickly.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: The structure of nerve cells is related to their function of carrying messages.

Question 8.

Assertion: Plant cells usually have a large vacuole.
Reason: Vacuoles help in storage, waste removal and maintaining cell shape.

Correct Option: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

Explanation: A large vacuole gives support and helps plant cells maintain shape.

Question 9.

Assertion: Curd forms better in cold milk than in lukewarm milk.
Reason: Lactobacillus grows well in warm conditions.

Correct Option: Assertion is false, but Reason is true.

Explanation: Curd forms better in lukewarm milk because Lactobacillus grows well in warm conditions.

Question 10.

Assertion: Viruses are acellular.
Reason: Viruses multiply only when they enter a living cell.

Correct Option: Both Assertion and Reason are true, but Reason is not the direct explanation of Assertion.

Explanation: Viruses are microscopic and acellular. They multiply inside living cells and may cause diseases.

Additional Case Study / Competency-Based Questions

Case Study 3: Observing Cells Under a Microscope

A teacher demonstrated how to observe onion peel cells. She stained the onion peel with safranin, placed it on a slide, added glycerin and carefully placed a coverslip. Under the microscope, students observed rectangular structures arranged closely together.

Question 1. What were the rectangular structures observed by the students?

Answer:

They were onion peel cells.

Question 2. Why was safranin used?

Answer:

Safranin was used to stain the cells and make them clearly visible.

Question 3. Why was glycerin added?

Answer:

Glycerin was added to prevent the cells from drying and to improve clarity.

Question 4. Name one extra outer layer present in onion peel cells.

Answer:

The extra outer layer is the cell wall.

Question 5. Why do onion peel cells look firm and compact?

Answer:

They look firm and compact because the cell wall provides rigidity and strength.

Case Study 4: Curd Formation

A student took two bowls. Bowl A contained lukewarm milk and bowl B contained cold milk. She added a small spoonful of curd to both bowls. Bowl A was kept in a warm place, while bowl B was kept in a cool place. After a few hours, bowl A turned into curd, while bowl B did not curdle properly.

Question 1. Which bacterium helps in curd formation?

Answer:

Lactobacillus helps in curd formation.

Question 2. What sugar is present in milk?

Answer:

The sugar present in milk is lactose.

Question 3. What acid makes curd sour?

Answer:

Lactic acid makes curd sour.

Question 4. Why did bowl A form curd faster?

Answer:

Bowl A formed curd faster because Lactobacillus grows well in warm conditions.

Question 5. Why did bowl B not curdle properly?

Answer:

Bowl B was kept in a cool place, which slowed the growth and activity of Lactobacillus.

Additional Diagram-Based Questions

Question 6.

In the diagram of a plant cell, which labelled part contains chlorophyll?

Answer:

Chloroplast contains chlorophyll.

Question 7.

In a plant cell diagram, which part maintains the shape of the cell and stores substances?

Answer:

The vacuole maintains the shape of the cell and stores substances.

Question 8.

In the diagram of levels of organisation, what comes after tissue?

Answer:

Organ comes after tissue.

Question 9.

In a diagram of pond water organisms, which organism has an irregular shape?

Answer:

Amoeba has an irregular shape.

Question 10.

In a root nodule diagram of a legume plant, which bacteria are present in the nodules?

Answer:

Rhizobium bacteria are present in the root nodules.

Additional HOTS / Application-Based Questions

Question 6.

A student observes that bread kept in a moist place develops cotton-like growth. Which microorganisms may be responsible and why?

Answer:

Fungi such as bread mould may be responsible. Moist conditions support the growth of microorganisms, and fungi can grow as cotton-like or powdery structures on food.

Question 7.

Why should fruit and vegetable peels not always be thrown away as waste?

Answer:

Fruit and vegetable peels can be converted into manure by microorganisms. This manure is rich in nutrients and improves soil fertility.

Question 8.

Why can a single cell like an egg develop into a multicellular organism?

Answer:

The egg has the ability to divide repeatedly. Through repeated division, it forms many cells that later organise into tissues, organs and organ systems.

Question 9.

A farmer wants to improve soil fertility naturally. Which crop type should he grow and why?

Answer:

He should grow legumes such as peas, beans or lentils because their root nodules contain Rhizobium bacteria. These bacteria trap nitrogen from air and enrich the soil.

Question 10.

Why is it incorrect to say that all tiny organisms are harmful?

Answer:

It is incorrect because many tiny organisms are useful. Microorganisms help in decomposition, manure formation, curd formation, fermentation, nitrogen enrichment, water cleaning, oxygen production and biofuel production.

Class 6 Science Chapter 2 Mindful Eating: Path to a healthy body Important Questions and Answers

Delhi Public School Notes

Mindful Eating: A Path to a Healthy Body Class 6 Science Questions and Answers

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Meta Description: Get premium CBSE Class 6 Science questions and answers for Mindful Eating: A Path to a Healthy Body. Includes very short answers, short answers, long answers, MCQs, assertion-reason, case study questions, diagram-based questions, HOTS, quick revision points and exam tips.

This premium question-answer blog post is designed for CBSE Class 6 Science students. It covers important concepts from the chapter Mindful Eating: A Path to a Healthy Body, including food diversity, nutrients, balanced diet, deficiency diseases, food tests, junk food, millets, food miles and mindful eating habits.

Class 6 Science Questions and Answers CBSE Class 6 Science Important Questions NCERT Science Chapter Questions Competency Based Science Questions

Chapter Overview

Class: Sixth

Subject: Science

Board: CBSE

Chapter: Mindful Eating: A Path to a Healthy Body

Main Theme: Food, nutrition, health and responsible eating

Useful For: School exams, unit tests and revision

Table of Contents

1. Very Short Answer Questions
2. Short Answer Questions
3. Long Answer Questions
4. MCQs
5. Assertion and Reason Questions
6. Case Study Questions
7. Diagram-Based Questions
8. HOTS Questions
9. Quick Revision Points
10. Final Exam Tips

Section A Very Short Answer Questions

Question 1.

What does the Sanskrit saying “annena jātāni jivanti” mean?

Answer:

It means food gives life to living beings.

Question 2.

Name one primary source of energy in our diet.

Answer:

Carbohydrates are one primary source of energy in our diet.

Question 3.

Which nutrient is present in glucose?

Answer:

Glucose is an example of a carbohydrate.

Question 4.

What are carbohydrates and fats called?

Answer:

Carbohydrates and fats are called energy-giving foods.

Question 5.

Which food component helps in growth and repair of the body?

Answer:

Proteins help in growth and repair of the body.

Question 6.

What are protein-rich foods called?

Answer:

Protein-rich foods are called body-building foods.

Question 7.

Name the deficiency disease caused by lack of Vitamin C.

Answer:

Lack of Vitamin C causes scurvy.

Question 8.

What is iodised salt?

Answer:

Iodised salt is common salt mixed with required quantities of salts of iodine.

Question 9.

What is roughage also known as?

Answer:

Roughage is also known as dietary fibre.

Question 10.

What colour indicates the presence of starch in a food item?

Answer:

A blue-black colour indicates the presence of starch.

Question 11.

Name one millet mentioned in the chapter.

Answer:

Jowar, bajra, ragi or sanwa.

Question 12.

What are millets also called?

Answer:

Millets are also called nutri-cereals.

Section B Short Answer Questions

Question 1.

Why do food habits vary across different regions of India?

Answer:

Food habits vary across different regions of India because different crops are grown in different regions depending on soil type and climatic conditions. Food choices also depend on taste preferences, culture and traditions.

Question 2.

How have culinary practices changed over time?

Answer:

Culinary practices have changed from traditional methods to modern methods. Earlier, people commonly used a chulha for cooking and sil-batta for grinding. Today, many people use a modern gas stove and an electrical grinder. These changes happened due to technological development, improved transportation and better communication.

Question 3.

Why does a marathon runner drink glucose water during or after a race?

Answer:

A marathon runner drinks glucose water because glucose provides instant energy. Glucose is a carbohydrate, and carbohydrates are one of the primary sources of energy in our diet.

Question 4.

Why are laddoos rich in ghee and nuts commonly eaten in winter?

Answer:

Laddoos made with ghee, nuts and seeds are rich in fats. Fats are a source of stored energy and help provide energy to keep the body warm during winter.

Question 5.

Why are vitamins and minerals called protective nutrients?

Answer:

Vitamins and minerals are called protective nutrients because they protect our body from diseases, help the body fight infections and keep us healthy.

Question 6.

Why should fruits and vegetables be washed before eating?

Answer:

Fruits and vegetables should be thoroughly washed before eating to make them clean and safe for consumption. However, washing cut or peeled fruits and vegetables may result in the loss of some vitamins, so they should preferably be washed before cutting or peeling.

Question 7.

What is the role of water in our diet?

Answer:

Water is an essential part of our diet. It helps the body absorb nutrients from food and removes waste from the body through sweat and urine. We should drink sufficient water regularly to stay healthy.

Question 8.

What are junk foods? Give two examples.

Answer:

Junk foods are foods that contain high levels of sugar and fats but very low amounts of proteins, vitamins, minerals and dietary fibres. Examples include potato wafers, candy bars and carbonated drinks.

Question 9.

Why are millets considered important for a balanced diet?

Answer:

Millets are important because they are good sources of vitamins, minerals like iron and calcium, and dietary fibres. They contribute significantly to a balanced diet and are known as nutri-cereals.

Question 10.

What is food miles?

Answer:

Food miles refers to the distance travelled by a food item from the place where it is produced to the consumer. We should try to minimise food miles by choosing locally grown food whenever possible.

Section C Long Answer Questions

Question 1.

Explain the major nutrients present in food and their functions.

Answer:

The major nutrients present in food are carbohydrates, fats, proteins, vitamins and minerals.

• Carbohydrates: They are one of the primary sources of energy. Examples include wheat, rice, maize, potato, sweet potato, banana, pineapple and mango.
• Fats: They provide stored energy. Examples include ghee, oils, nuts, seeds, butter and curd.
• Proteins: They help in growth and repair of the body. Pulses, beans, peas, nuts, milk, paneer, egg, fish and meat are sources of protein.
• Vitamins: They help protect the body from diseases. Examples include Vitamins A, B1, C and D.
• Minerals: They help in different body functions. Calcium, iodine and iron are important minerals.

Question 2.

What is a balanced diet? Why is it important?

Answer:

A balanced diet is a diet that contains all essential nutrients, roughage and water in the right amount for proper growth and development of the body.

It is important because:

• It provides energy for daily activities.
• It supports growth and development.
• It helps repair the body.
• It protects the body from diseases.
• It keeps the digestive system healthy through roughage.
• It helps remove waste from the body through sufficient water intake.

Question 3.

Describe the tests used to detect starch, fats and proteins in food items.

Answer:

Test for starch: A small piece of the food item is placed on a dish and 2–3 drops of diluted iodine solution are added. If the food turns blue-black, starch is present.

Test for fats: A food item is placed on a piece of paper and pressed. If an oily patch appears and light can faintly pass through it, fat is present.

Test for proteins: The food item is made into a paste or powder and placed in a test tube. Water is added, followed by copper sulfate solution and caustic soda solution. If the content turns violet, protein is present.

Question 4.

Explain deficiency diseases with examples from the chapter.

Answer:

Deficiency diseases occur when one or more nutrients are lacking in the diet for a long time.

• Scurvy: It is caused by deficiency of Vitamin C. Symptoms include bleeding gums and slow healing of wounds. Citrus fruits like lemons and oranges help in curing it.
• Goitre: It is caused due to lack of iodine. The main symptom is swelling at the front of the neck. Iodised salt helps prevent iodine deficiency.
• Rickets: It is caused by deficiency of Vitamin D. It leads to soft and bent bones.
• Anaemia: It is linked with lack of iron. Symptoms include weakness and shortness of breath.
• Beriberi: It is caused by deficiency of Vitamin B1 and may cause swelling, tingling or burning sensation in feet and hands, and trouble in breathing.

Question 5.

Why should we avoid junk food and prefer healthy food?

Answer:

We should avoid junk food because it contains high amounts of sugar and fats but very low amounts of proteins, vitamins, minerals and dietary fibres. Frequent consumption of such food is unhealthy and may make a person obese. Obesity can further lead to several health problems.

Healthy food, on the other hand, provides essential nutrients, roughage and water. It gives energy, supports growth, repairs the body and protects us from diseases. Therefore, we should eat a balanced diet and avoid frequent consumption of junk food.

Question 6.

Explain why locally grown and plant-based food is good for the body and environment.

Answer:

Locally grown and plant-based food is good for the body because it can provide nutrients such as carbohydrates, proteins, vitamins, minerals and dietary fibres. It is also good for the environment because it helps reduce food miles, which means the distance food travels from the place of production to the consumer. Reducing food miles can help support local producers and reduce unnecessary transportation. Therefore, eating local food is a mindful and environment-friendly choice.

Section D MCQs

Question 1.

Which of the following is a primary source of energy in our diet?

• A. Vitamins
• B. Minerals
• C. Carbohydrates
• D. Roughage

Correct Answer: C. Carbohydrates

Explanation: Carbohydrates are one of the primary sources of energy in our diet.

Question 2.

Which of these is a source of carbohydrates?

• A. Rice
• B. Butter
• C. Paneer
• D. Fish

Correct Answer: A. Rice

Explanation: Rice is a cereal and a source of carbohydrates.

Question 3.

Protein-rich foods are called:

• A. Energy-giving foods
• B. Body-building foods
• C. Junk foods
• D. Food miles

Correct Answer: B. Body-building foods

Explanation: Proteins help in growth and repair of the body, so protein-rich foods are called body-building foods.

Question 4.

Which vitamin deficiency causes scurvy?

• A. Vitamin A
• B. Vitamin B1
• C. Vitamin C
• D. Vitamin D

Correct Answer: C. Vitamin C

Explanation: Scurvy is caused due to deficiency of Vitamin C.

Question 5.

Which mineral is important for blood?

• A. Iodine
• B. Iron
• C. Calcium
• D. Sodium

Correct Answer: B. Iron

Explanation: Iron is an important component of blood.

Question 6.

An oily patch on paper indicates the presence of:

• A. Starch
• B. Fat
• C. Protein
• D. Vitamin C

Correct Answer: B. Fat

Explanation: Food items containing fat leave an oily patch on paper.

Question 7.

Which colour shows the presence of protein in a food test?

• A. Blue-black
• B. Violet
• C. Green
• D. Red

Correct Answer: B. Violet

Explanation: Violet colour indicates the presence of proteins in a food item.

Question 8.

Which of the following is also called roughage?

• A. Dietary fibre
• B. Glucose
• C. Salt
• D. Fat

Correct Answer: A. Dietary fibre

Explanation: Dietary fibre is also known as roughage.

Question 9.

Which of the following is a millet?

• A. Potato
• B. Ragi
• C. Paneer
• D. Butter

Correct Answer: B. Ragi

Explanation: Ragi is a millet and is also called a nutri-cereal.

Question 10.

Which of these is an example of junk food mentioned in the chapter?

• A. Roasted chana
• B. Green leafy vegetables
• C. Potato wafers
• D. Wholegrains

Correct Answer: C. Potato wafers

Explanation: Potato wafers are listed as junk food because they contain high fat and have low amounts of many protective nutrients.

Section E Assertion and Reason Questions

Options:

A. Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.

B. Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.

C. Assertion is true, but Reason is false.

D. Assertion is false, but Reason is true.

Question 1.

Assertion: Carbohydrates and fats are called energy-giving foods.

Reason: Carbohydrates and fats provide energy for performing various activities.

Correct Answer: A

Explanation: Both statements are true, and the reason correctly explains why carbohydrates and fats are called energy-giving foods.

Question 2.

Assertion: Proteins are called body-building foods.

Reason: Proteins help in growth and repair of our body.

Correct Answer: A

Explanation: Proteins help the body grow and repair itself, so they are correctly called body-building foods.

Question 3.

Assertion: Iodised salt helps prevent goitre.

Reason: Goitre is caused due to deficiency of iodine.

Correct Answer: A

Explanation: Iodised salt contains salts of iodine, and iodine deficiency can cause goitre.

Question 4.

Assertion: Junk foods should be eaten frequently for good health.

Reason: Junk foods contain high levels of sugar and fats but little protein, vitamins, minerals and dietary fibres.

Correct Answer: D

Explanation: The assertion is false because junk food should not be eaten frequently. The reason is true because junk foods are high in sugar and fats and low in many important nutrients.

Question 5.

Assertion: Millets are also called nutri-cereals.

Reason: Millets are good sources of vitamins, minerals and dietary fibres.

Correct Answer: A

Explanation: Millets are called nutri-cereals because they provide many nutrients needed for the normal functioning of the body.

Section F Case Study / Competency-Based Questions

Case Study 1: Sailors and Scurvy

In earlier times, during long voyages, sailors often suffered from bleeding and swollen gums. During a voyage in 1746, Scottish physician James Lind observed that sailors who consumed lemons and oranges recovered from these symptoms. Bleeding and swollen gums are symptoms of a disease called scurvy.

Question 1.

Which disease did the sailors suffer from?

Answer:

They suffered from scurvy.

Question 2.

What are the symptoms of scurvy mentioned in the case?

Answer:

The symptoms mentioned are bleeding and swollen gums.

Question 3.

Which fruits helped the sailors recover?

Answer:

Lemons and oranges helped the sailors recover.

Question 4.

Which vitamin deficiency causes scurvy?

Answer:

Scurvy is caused due to deficiency of Vitamin C.

Question 5.

Why should citrus fruits be included in the diet?

Answer:

Citrus fruits contain Vitamin C, which helps the body fight diseases and prevents deficiency disease like scurvy.

Case Study 2: Iodised Salt and Goitre

In the 1960s, Indian scientists found that many people in the Himalayan region and Northern plains of India had swelling at the front of the neck. This happened due to deficiency of iodine in the soil, which caused lack of iodine in local food and water. Common salt was supplemented with iodine to prepare iodised salt. Consumption of iodised salt visibly reduced the symptoms.

Question 1.

Which disease is linked with swelling at the front of the neck?

Answer:

Swelling at the front of the neck is a symptom of goitre.

Question 2.

Which mineral deficiency causes goitre?

Answer:

Goitre is caused due to deficiency of iodine.

Question 3.

What is iodised salt?

Answer:

Iodised salt is common salt mixed with required quantities of salts of iodine.

Question 4.

Why did the symptoms reduce after people consumed iodised salt?

Answer:

The symptoms reduced because iodised salt supplied iodine to the body and helped overcome iodine deficiency.

Question 5.

Name two sources of iodine mentioned in the chapter.

Answer:

Seaweed, water chestnut and iodised salt are sources of iodine.

Case Study 3: Potato Wafers and Roasted Chana

A packet of potato wafers has high energy and fat content, while roasted chana has more protein and dietary fibre. The chapter explains that foods with high sugar and fats but very low protein, vitamins, minerals and dietary fibres are called junk foods.

Question 1.

Which food item is healthier: potato wafers or roasted chana?

Answer:

Roasted chana is healthier because it contains more protein and dietary fibre and less fat compared to potato wafers.

Question 2.

Which of the two can be labelled as junk food?

Answer:

Potato wafers can be labelled as junk food.

Question 3.

Why are junk foods harmful when consumed frequently?

Answer:

Junk foods can make a person obese and may lead to several health problems because they are high in sugar and fats and low in important nutrients.

Question 4.

What should we eat instead of junk food?

Answer:

We should eat a balanced diet containing essential nutrients, roughage and water.

Section G Diagram-Based Questions

Question 1.

In a diagram showing sources of carbohydrates, label any four carbohydrate-rich food items.

Answer:

Four carbohydrate-rich food items are wheat, rice, maize and potato. Other examples include sweet potato, banana, pineapple and mango.

Question 2.

In a diagram showing sources of fats, label any four sources of fats.

Answer:

Four sources of fats are groundnut, walnut, almonds and butter. Other sources include sunflower seeds, sesame seeds, soya bean, curd and oils.

Question 3.

Observe a diagram showing plant and animal sources of proteins. Classify the following as plant or animal sources: gram, peas, fish, eggs, paneer.

Answer:

Plant sources: Gram and peas.

Animal sources: Fish, eggs and paneer.

Question 4.

In a diagram of the starch test, what material is added to the food item?

Answer:

Diluted iodine solution is added to the food item. If the food turns blue-black, starch is present.

Question 5.

In a diagram of the protein test, which colour indicates the presence of protein?

Answer:

A violet colour indicates the presence of protein.

Question 6.

In a diagram comparing traditional and modern cooking tools, name one traditional and one modern cooking tool.

Answer:

Traditional cooking tool: Chulha.

Modern cooking tool: Gas stove.

Section H HOTS / Application-Based Questions

Question 1.

Riya eats only rice and potato every day. Which important food components may be missing from her diet?

Answer:

Rice and potato mainly provide carbohydrates. Riya’s diet may lack sufficient proteins, fats, vitamins, minerals, roughage and possibly adequate variety. She should include pulses, vegetables, fruits, milk products, nuts and sufficient water to make her diet more balanced.

Question 2.

A child has bleeding gums and slow healing of wounds. Which nutrient may be lacking and what foods should be included?

Answer:

The child may be lacking Vitamin C. Foods such as amla, guava, green chilli, orange and lemon should be included in the diet.

Question 3.

Why should we not wash fruits and vegetables after cutting them?

Answer:

Washing cut or peeled fruits and vegetables may result in the loss of some vitamins. Therefore, fruits and vegetables should be washed thoroughly before cutting or peeling.

Question 4.

Your friend says, “Roughage gives no nutrients, so it is useless.” Is your friend correct?

Answer:

No, the statement is incorrect. Roughage does not provide nutrients, but it is still an essential component of food. It helps the body remove undigested food and ensures smooth passage of stools.

Question 5.

Why do sportspersons need proteins in larger quantities?

Answer:

Sportspersons need proteins in larger quantities because proteins help build muscles and repair body tissues. Their physical activity is high, so their body needs more body-building nutrients.

Question 6.

How can eating locally grown food reduce food miles?

Answer:

Eating locally grown food reduces the distance food travels from the place of production to the consumer. This decreases food miles and supports local producers.

Question 7.

Why should we take only as much food as we can consume?

Answer:

We should take only as much food as we can consume because wasting food ignores the time and effort of farmers and other community members who bring food from farm to plate. It also helps reduce food wastage.

Revision Quick Revision Points

• Food is essential for life and gives energy to living beings.
• Food habits vary across regions due to locally grown crops, soil, climate, culture, tradition and taste preferences.
• Culinary practices have changed from traditional methods like chulha and sil-batta to modern methods like gas stove and electrical grinder.
• The major nutrients are carbohydrates, fats, proteins, vitamins and minerals.
• Carbohydrates and fats are energy-giving foods.
• Proteins are body-building foods because they help in growth and repair.
• Vitamins and minerals are protective nutrients.
• Deficiency of Vitamin C causes scurvy.
• Deficiency of iodine causes goitre.
• Deficiency of Vitamin D causes rickets.
• Roughage helps remove undigested food and ensures smooth passage of stools.
• Water helps absorb nutrients and remove waste through sweat and urine.
• A balanced diet contains all essential nutrients, roughage and water in the right amount.
• Junk foods are high in sugar and fats but low in proteins, vitamins, minerals and dietary fibres.
• Millets like jowar, bajra, ragi and sanwa are called nutri-cereals.
• Food miles means the distance travelled by food from production place to consumer.
• We should eat healthy, share food, respect food and avoid wasting it.

Food Component	Main Function	Examples / Sources
Carbohydrates	Provide energy	Wheat, rice, maize, potato, banana
Fats	Provide stored energy	Ghee, oils, nuts, seeds, butter
Proteins	Growth and repair	Pulses, beans, peas, nuts, milk, paneer, eggs
Vitamins	Protect from diseases	Fruits, vegetables, milk, sunlight for Vitamin D
Minerals	Maintain body functions	Calcium, iodine, iron-rich foods
Roughage	Helps remove undigested food	Green leafy vegetables, fruits, wholegrains, pulses, nuts
Water	Absorbs nutrients and removes waste	Drinking water, fruits and vegetables

Exam Tips Final Exam Tips

Tip 1: Learn the difference between energy-giving foods, body-building foods and protective nutrients.

Tip 2: Memorise the deficiency diseases: Vitamin C—Scurvy, Iodine—Goitre, Vitamin D—Rickets, Iron—Anaemia.

Tip 3: Practise food test questions carefully: iodine test for starch, oily patch test for fats and violet colour test for proteins.

Tip 4: In long answers, write point-wise with examples of food sources.

Tip 5: For competency-based questions, connect the concept with real-life food choices, balanced diet, junk food and food wastage.

Conclusion

The chapter Mindful Eating: A Path to a Healthy Body teaches that food is not only necessary for energy but also for growth, repair, protection from diseases and overall health. A healthy lifestyle depends on eating a balanced diet, avoiding junk food, including fruits, vegetables, roughage and water, respecting food and reducing food wastage. Students should revise nutrients, deficiency diseases, food tests, millets and food miles carefully for exams.

Delhi Public School Notes brings this premium CBSE Class 6 Science question-answer set to help students prepare confidently for school exams, unit tests and quick revision.