---
title: "NCERT Solutions Class 9 Science Cell: The Building Block of Life"
url: https://www.swavid.com/science/class/9/chapter/cell-the-building-block-of-life/ncert-solutions
dateModified: 2026-10-07T16:19:50+00:00
---

# NCERT Solutions Class 9 Science Cell: The Building Block of Life

This chapter's questions cover fundamental biological concepts related to cell structure, organelles, microscopy, osmosis, and cell division.

Free PDF (16 pages): https://www.swavid.com/api/seo/pdf/ncert/science/class-9/swavid-ncert-solutions-class-9-science-chapter-2-cell-the-building-block-of-life-3d3432b679.pdf

## Think It Over

### Question 1

*2 marks · Very short answer*

Where does a cell come from?

**Solution**

1. According to the Cell Theory, new cells are formed only from pre-existing cells through cell division.

**Answer:** Cells come from pre-existing cells through the process of cell division.

> Common mistake: Writing that cells arise spontaneously without mentioning pre-existing cells or cell division.

### Question 2

*3 marks · Short answer*

How have technological interventions facilitated the creation of new knowledge in understanding the world beyond the naked eye?

**Solution**

1. Technological interventions such as the invention and continuous improvement of light microscopes and electron microscopes have enhanced resolution, contrast, and magnification.
2. A light microscope uses lenses to magnify tiny structures like cells that are beyond the limit of resolution of the human eye (0.1 mm).
3. An electron microscope uses a beam of electrons instead of light to reveal the fine sub-cellular details of a cell at the nanometre scale with remarkable clarity.

**Answer:** Technological interventions like light and electron microscopes magnify microscopic structures and improve resolution and contrast, enabling scientists to study cells and organelles beyond the naked eye.

> Common mistake: Confusing the working principles of light microscopes and electron microscopes.

### Question 3

*3 marks · Short answer*

How is the cell structural and functional unit of life?

**Solution**

1. All living organisms are made up of cells, which form the basic structural framework of tissues, organs, and organ systems.
2. Every cell contains specialised components called organelles that carry out vital life processes such as respiration, protein synthesis, and waste removal.
3. Thus, the cell is called the structural unit because it builds the body, and the functional unit because all life activities take place within it.

**Answer:** The cell is the structural unit as it forms the basic building block of all living bodies, and the functional unit as all life processes and metabolic activities are performed within it.

> Common mistake: Explaining only structure or only function instead of both.

### Question 4

*2 marks · Very short answer*

How does a cell multiply?

**Solution**

1. A cell multiplies through the process of cell division, which produces new cells from pre-existing cells.

**Answer:** A cell multiplies through cell division, which includes types such as mitosis and meiosis.

> Common mistake: Failing to name cell division as the primary method of cellular multiplication.

## Pause and Ponder

### Question 1

*3 marks · Short answer*

What argument would you give for the necessity of a cell wall in plants usually fixed in one place versus in animals usually moving from one place to the other?

**Solution**

1. Plants are fixed in one place and exposed to harsh environmental stresses such as high-speed winds, heavy rain, and extreme temperatures.
2. The rigid cell wall provides mechanical support and helps plant cells maintain their shape, allowing plants to stay upright and firm.
3. Animals generally move from place to place and lack a rigid cell wall, which gives animal cells cellular flexibility required for movement and functioning of animal tissues.

**Answer:** Plants need a rigid cell wall to withstand environmental stresses and remain upright since they are fixed in one place, whereas mobile animals need flexible cells without a cell wall for locomotion.

> Common mistake: Writing that animals have cell walls or confusing the protective role of the cell wall with the cell membrane.

### Question 2

*3 marks · Short answer*

What consequences would you predict for a plant cell if its cell wall were to become as flexible as a cell membrane?

**Solution**

1. If the cell wall of a plant cell became as flexible as a cell membrane, it would lose its rigidity and structural strength.
2. The plant cell would not be able to maintain its shape or withstand the internal pressure built up by water entering the central vacuole through osmosis.
3. Consequently, the plant would lose its firmness, fail to stay upright, and wilt easily under environmental stress.

**Answer:** The plant cell would lose its rigid shape, fail to maintain upright posture, and the plant would wilt easily without a firm cell wall to withstand internal osmotic pressure.

> Common mistake: Forgetting that plant cells rely on the rigid cell wall to counteract high internal water pressure.

### Question 3

*3 marks · Short answer*

Why is it important to cut the two potato pieces in roughly equal size and measure their initial weight before placing them in different liquids?

**Solution**

1. Cutting the two potato pieces to roughly equal size ensures that both pieces have approximately the same initial surface area and volume for osmosis.
2. Measuring their initial weight provides a baseline to accurately calculate the change in weight caused by water entering or leaving the cells.
3. This makes the experiment fair and allows a correct comparison of the effects of plain water versus concentrated salt or sugar solution.

**Answer:** Equal initial size and weight are necessary to maintain a controlled experiment, ensuring that differences in final weight depend only on the surrounding liquid and not on initial size differences.

> Common mistake: Stating it is just to make the experiment look neat without mentioning experimental control and accurate comparison.

## Pause and Ponder

### Question 4

*3 marks · Short answer*

Do white flowers contain any pigment? Give reasons.

**Solution**

1. White flowers do contain plastids, but these are colourless plastids called leucoplasts or chromoplasts lacking coloured pigments.
2. They do not contain coloured pigments like chlorophyll (green) or anthocyanins/carotenoids in chromoplasts that impart distinct colours.
3. Therefore, white flowers appear white because they reflect all light and lack light-absorbing pigments in their petals.

**Answer:** Yes, white flowers contain colourless plastids (leucoplasts) but lack coloured pigments like chlorophyll or carotenoids.

> Common mistake: Students often think white flowers have no plastids at all, forgetting about leucoplasts.

### Question 5

*3 marks · Short answer*

Draw a well-labelled schematic diagram of a plant or an animal cell using these clues—
(i) Nucleus appears as a dark and round body inside the cell.
(ii) ER spreads like a network of extended nuclear envelope.
(iii) Mitochondria and chloroplasts are rod shaped.
You may refer to Fig. 2.10.

**Solution**

1. Diagram: Draw a plant cell showing a distinct cell wall and cell membrane enclosing the cytoplasm.
2. Label the nucleus as a dark and round body with a double-layered nuclear membrane, and show the endoplasmic reticulum spreading as a network connected to it.
3. Label rod-shaped mitochondria and rod-shaped chloroplasts in the cytoplasm, along with a large central vacuole.

**Answer:** A well-labelled schematic diagram of a plant cell showing the nucleus, ER network, and rod-shaped mitochondria and chloroplasts.

> Common mistake: Drawing chloroplasts or mitochondria as spherical instead of rod-shaped as specified in the clues.

## Pause and Ponder

### Question 6

*3 marks · Short answer*

Instead of many small ones, why does a cell not have a single giant mitochondrion? How does this relate to the concept of surface area?

**Solution**

1. A cell requires a large surface area for chemical reactions involved in cellular respiration and energy production.
2. As a cell or organelle increases in size, its volume increases much faster than its surface area, reducing the efficiency of transport and exchange.
3. Having many small mitochondria provides a large total surface area through folded inner membranes (cristae) for efficient ATP production compared to a single giant mitochondrion.

**Answer:** Many small mitochondria provide a larger surface area-to-volume ratio for efficient cellular respiration and energy production than a single giant mitochondrion.

> Common mistake: Confusing surface area-to-volume ratio limitations with just the total volume of the cell.

### Question 7

*3 marks · Short answer*

If the skin cells start dividing by meiosis instead of mitosis, what do you think will happen to a cut on the skin?

**Solution**

1. Skin cells normally grow and divide by mitosis to produce genetically identical cells for growth and repair.
2. Meiosis is a two-step division process that occurs only in reproductive organs to produce gametes with half the chromosome number.
3. If skin cells started dividing by meiosis, the resulting cells would have half the number of chromosomes and would not form the identical somatic tissue required to heal the cut properly.

**Answer:** The cut on the skin would not heal properly because meiosis produces gametes with half the chromosome number instead of identical somatic cells required for tissue repair.

> Common mistake: Failing to state that meiosis halves the chromosome number.

## Revise, Reflect, Refine

### Question 1

*3 marks · Short answer*

Differentiate between the following pairs of terms based on the clues given in parentheses:
(i) Cell membrane and cell wall (permeability)
(ii) RER and SER (structure)
(iii) Chloroplasts and chromoplasts (pigments)

**Part (i)**

1. The cell membrane is selectively permeable, allowing some substances to pass through while blocking others.
2. The cell wall is permeable, allowing water and dissolved minerals to pass through freely.

Answer (i): Cell membrane is selectively permeable, whereas cell wall is permeable.

**Part (ii)**

1. Rough Endoplasmic Reticulum (RER) has ribosomes attached to its surface, giving it a rough appearance under an electron microscope.
2. Smooth Endoplasmic Reticulum (SER) does not have ribosomes on its surface, making it look smooth.

Answer (ii): RER has attached ribosomes on its surface, while SER lacks ribosomes.

**Part (iii)**

1. Chloroplasts contain the green pigment chlorophyll for photosynthesis.
2. Chromoplasts contain pigments other than chlorophyll, such as yellow, orange, or red pigments.

Answer (iii): Chloroplasts contain green chlorophyll pigments, whereas chromoplasts contain other colored pigments like yellow, orange, or red.

**Answer:** Differentiated between cell membrane and cell wall, RER and SER, and chloroplasts and chromoplasts based on their permeability, structure, and pigments respectively.

> Common mistake: Confusing the permeability of the cell membrane with that of the cell wall.

### Question 2

*1 mark · MCQ*

Two similar animal cells are placed in two different solutions:
- Cell X is placed in pure water.
- Cell Y is placed in a concentrated salt solution.
Cells are observed after some time. Cell X swells, and Cell Y shrinks. Which statement provides the correct explanation for the above observations?

- Salt molecules moved into Cell Y, causing it to shrink.
- Water moved into Cell X and more water moved out of Cell Y than the salt solution entered in it.
- Water moved into Cell X and moved out of Cell Y through the cell membrane.
- Solute movement caused osmosis in both cells.

**Solution**

1. Cell X is placed in pure water, so water moves into the cell due to osmosis, causing it to swell.
2. Cell Y is placed in a concentrated salt solution, so water moves out of the cell, causing it to shrink.

**Answer:** (iii) Water moved into Cell X and moved out of Cell Y through the cell membrane.

> Common mistake: Assuming that salt molecules moved into Cell Y to cause the shrinking.

### Question 3

*3 marks · Short answer*

Look at the diagram of a cell in Fig. 2.20. Identify the parts labelled from (a) to (g) and correctly match them with their functions given below:
(i) Controlling all the activities of a cell.
(ii) Site of cellular respiration.
(iii) Storage organelle that also provides rigidity to the cell.
(iv) Separates the cell contents from surroundings.
(v) Provides structural rigidity to the cell.
(vi) Packs and stores materials received from ER.
(vii) Helps in manufacturing food.

**Part (i)**

1. The nucleus controls all the activities of a cell.

Answer (i): (b) Nucleus

**Part (ii)**

1. Mitochondria are the site of cellular respiration.

Answer (ii): (f) Mitochondrion

**Part (iii)**

1. The large central vacuole is the storage organelle that helps maintain cell pressure and rigidity.

Answer (iii): (c) Vacuole

**Part (iv)**

1. The cell membrane separates the cell contents from its surroundings.

Answer (iv): (e) Cell membrane

**Part (v)**

1. The cell wall provides structural rigidity to the plant cell.

Answer (v): (g) Cell wall

**Part (vi)**

1. The Golgi apparatus packs and stores materials received from the ER.

Answer (vi): (d) Golgi apparatus

**Part (vii)**

1. Chloroplasts help in manufacturing food through photosynthesis.

Answer (vii): (a) Chloroplast

**Answer:** Correctly matched parts (a) to (g) from Fig. 2.20 with their respective cell functions.

> Common mistake: Confusing chloroplasts and mitochondria labels in the plant cell diagram.

### Question 4

*1 mark · MCQ*

Which of the following option(s) of the pairs of cell organelles are correctly placed under the given categories?

- Leucoplast | Cell wall
- Mitochondria | Ribosome
- Cell wall | Golgi apparatus
- Lysosome | Endoplasmic reticulum

**Solution**

1. Leucoplasts are plastids found exclusively in plant cells, while cell walls are present in plant cells and absent in animal cells.
2. Mitochondria and ribosomes are found in both plant and animal cells, whereas Golgi apparatus and endoplasmic reticulum are present in both types of eukaryotic cells.

**Answer:** (i) Leucoplast | Cell wall

> Common mistake: Confusing organelles that are common to both eukaryotic cells with those exclusive to plant cells.

### Question 5

*3 marks · Short answer*

Two students, Renu and Rohit, were having a discussion on the plastids. Renu emphasised that all parts of the plants, even roots, contain plastids. However, Rohit did not agree with the statement and told her that plastids are absent in plant roots since the roots are underground and do not need to perform photosynthesis. Who is correct? Justify your answer.

**Solution**

1. Renu is correct because not all plastids contain chlorophyll or perform photosynthesis.
2. Leucoplasts are colourless plastids present in underground plant parts like roots and tubers (such as in potatoes) to store food materials like starch.
3. Therefore, plastids are present in plant roots even though they do not perform photosynthesis.

**Answer:** Renu is correct. Plant roots contain leucoplasts, which are colourless plastids that store food materials.

> Common mistake: Assuming all plastids are chloroplasts and thus absent in underground roots.

### Question 6

*5 marks · Long answer*

Mitochondria and chloroplasts are two important organelles in a plant cell. Discuss how these two organelles are structurally and functionally similar to each other, and different from each other.

**Solution**

1. Structural similarities: Both mitochondria and chloroplasts are double-membrane-bound organelles and contain their own DNA and ribosomes.
2. Functional similarities: Both are involved in energy conversions within the cell; mitochondria produce ATP via cellular respiration, while chloroplasts capture light energy to synthesize food via photosynthesis.
3. Structural differences: Mitochondria have an inner membrane folded into cristae to increase surface area, whereas chloroplasts contain stroma and disc-shaped membrane structures containing chlorophyll.
4. Functional differences: Mitochondria break down glucose to release energy, while chloroplasts synthesize food by trapping solar energy.
5. Evolutionary link: Their possession of independent DNA and ribosomes suggests they share an evolutionary history with single-celled bacterial organisms.

**Answer:** Mitochondria and chloroplasts are similar in having double membranes, DNA, and ribosomes, but differ in their internal folding structures and their specific roles in cellular respiration versus photosynthesis.

> Common mistake: Confusing the inner membrane folds (cristae) of mitochondria with the internal stroma and disc structures of chloroplasts.

### Question 7

*1 mark · MCQ*

Which of the following pairs of cell organelles contains DNA?

- Chloroplasts, Ribosomes
- Mitochondria, Nucleus
- Golgi bodies, Ribosomes
- Nucleus, Lysosomes

**Solution**

1. Mitochondria and chloroplasts contain their own DNA and ribosomes, allowing them to make some of their own proteins.
2. The nucleus also contains the genetic material in the form of DNA.
3. Therefore, the correct pair of organelles containing DNA is Mitochondria and Nucleus.

**Answer:** (ii) Mitochondria, Nucleus

> Common mistake: Confusing ribosomes as DNA-containing structures.

### Question 8

*5 marks · Long answer*

A researcher carried out an experiment in which she took two carrots of similar size. She placed one carrot in plain water and the other carrot in concentrated salt solution (Fig. 2.21). After 24 hours she recorded her observations.
(i) What hypothesis does she want to test through this experiment?
(ii) What would you suggest for the improvement of this experiment?
(iii) Why does the carrot in plain water stay stiff and crunchy, but the carrot in concentrated salt solution become rubbery and limp?

**Part (i)**

1. The researcher wants to test the hypothesis that water moves across the cell membrane of plant cells (carrots) by osmosis when placed in solutions of different concentrations.

Answer (i): To test the effect of osmosis on carrot cells placed in plain water and concentrated salt solution.

**Part (ii)**

1. To improve the experiment, multiple carrots of identical size and mass should be used to calculate average weight changes, and initial and final masses should be recorded accurately using a weighing balance.

Answer (ii): Use multiple carrots of the same size and measure initial and final weights for quantitative accuracy.

**Part (iii)**

1. In plain water, water enters the carrot cells by endosmosis, making them turgid so the carrot stays stiff and crunchy.
2. In concentrated salt solution, water moves out of the carrot cells by exosmosis, causing them to lose water and become rubbery and limp.

Answer (iii): Plain water enters cells by endosmosis keeping them stiff, while salt solution draws water out by exosmosis making them limp.

**Answer:** The experiment tests osmosis in carrots, where water moves in or out based on the concentration gradient, affecting their turgidity.

> Common mistake: Confusing diffusion with osmosis.

### Question 9

*3 marks · Short answer*

Indicate the presence or absence of following structures in bacterial and animal cells:

**Solution**

1. Bacterial cells (prokaryotic) lack a well-defined nucleus and membrane-bound organelles like mitochondria, Golgi complex, and chromoplasts, but contain a nucleoid (chromosome without a nuclear membrane).
2. Animal cells (eukaryotic) possess a well-defined nucleus, membrane-bound organelles like mitochondria and Golgi complex, but lack chromoplasts (which are found in plant cells).
3. Both cell types contain chromosomes and cell membranes.

**Answer:** Bacterial cells lack a true nucleus, mitochondria, Golgi complex, and chromoplasts, whereas animal cells have a true nucleus, mitochondria, and Golgi complex, but lack chromoplasts.

> Common mistake: Thinking bacteria have a true nucleus or membrane-bound organelles.

### Question 10

*4 marks · Long answer*

Carry out the following experiment:
Take four peeled potato halves and scoop each one out to make potato cups. One of these potato cups should be made from a boiled potato. Place each of the potato cups in a beaker containing water (Fig. 2.22). Now, set up the experiment as follows:
(a) Keep Cup A empty.
(b) Add one teaspoon sugar in Cup B.
(c) Add one teaspoon salt in Cup C.
(d) Add one teaspoon sugar in the boiled potato in Cup D.
Observe the four potato cups at least two hours and answer the following questions:
(i) Explain why water gathers in the hollowed portion of Cup B and Cup C.
(ii) Why is Cup A necessary for this experiment?
(iii) Explain why water does not gather in the hollowed portions of Cups A and D.

**Part (i)**

1. Sugar and salt solutions inside Cups B and C create a higher solute concentration compared to the pure water in the beaker.
2. Water moves from the beaker through the living potato cells into the hollowed portion by osmosis.

Answer (i): Water moves into the cups by osmosis because the sugar and salt solutions inside have a higher solute concentration than plain water.

**Part (ii)**

1. Cup A acts as a control experiment to show that water does not gather in the hollowed portion on its own without a solute gradient.

Answer (ii): Cup A serves as a control to prove that a solute concentration difference is required for water to gather.

**Part (iii)**

1. In Cup A, there is no solute inside the hollowed portion to create a concentration gradient.
2. In Cup D, the potato is boiled, which kills the cells and destroys the selectively permeable nature of the cell membranes, stopping osmosis.

Answer (iii): Cup A lacks a solute gradient, while Cup D uses a boiled potato whose dead cells cannot perform osmosis.

**Answer:** Water gathers in hollowed portions containing high solute concentrations due to osmosis across living potato cell membranes.

> Common mistake: Forgetting that boiling destroys the selective permeability of cell membranes.

### Question 11

*1 mark · MCQ*

Identify the pair that incorrectly matches the cell organelle with its function.

- Ribosome — Protein synthesis
- SER — Lipid and cellulose synthesis
- Lysosome — Digestion of foreign agents

**Solution**

1. Ribosomes are the sites of protein synthesis, which is a correct match.
2. Smooth Endoplasmic Reticulum (SER) is involved in the synthesis and storage of fats and hormones, not cellulose (cellulose is found in plant cell walls).
3. Lysosomes contain digestive enzymes to break down foreign agents and waste, which is a correct match.
4. Therefore, the incorrectly matched pair is SER — Lipid and cellulose synthesis.

**Answer:** (ii) SER — Lipid and cellulose synthesis

> Common mistake: Assuming SER synthesises cellulose because plant cells have cellulose walls.

### Question 12

*3 marks · Short answer*

What outcome do you expect, if all the mitochondria are removed from a eukaryotic cell?

**Solution**

1. Mitochondria are known as the 'powerhouses of the cell' because they generate energy in the form of ATP through cellular respiration.
2. If all mitochondria are removed from a eukaryotic cell, it will fail to produce sufficient ATP for its activities.
3. Without energy currency, most cellular functions will stop, leading rapidly to cell death.

**Answer:** The cell will be unable to generate ATP (energy), leading to the stoppage of most cellular activities and eventual cell death.

> Common mistake: Stating that the cell will only slow down instead of undergoing cell death due to total lack of energy.

### Question 13

*3 marks · Short answer*

Which phenomenon inhibits the formation of tumors in the human body? Can plants also develop tumors? Explain.

**Solution**

1. Contact inhibition is the phenomenon in which cell division stops when animal cells come in contact with neighbouring cells, which inhibits the formation of tumours in the human body.
2. Yes, plants can also develop tumours.
3. However, plant cells do not show contact inhibition due to their rigid cell walls and follow a different pattern of growth when they undergo uncontrolled division.

**Answer:** Contact inhibition inhibits tumour formation in animal cells. Plants can also develop tumours due to uncontrolled cell division, though they do not show contact inhibition.

> Common mistake: Stating that plants cannot develop tumours because of their rigid cell walls.

### Question 14

*5 marks · Long answer*

The cell membrane of a cell is made up of proteins and lipids. Which cell organelles help in the synthesis of cell membrane? Write the path of these compounds from their site of synthesis to the cell membrane and show this through a labelled diagram.

**Solution**

1. Proteins are synthesized by the ribosomes attached to the Rough Endoplasmic Reticulum (RER).
2. Lipids (fats) are synthesized by the Smooth Endoplasmic Reticulum (SER).
3. These proteins and lipids synthesized by the endoplasmic reticulum are sent to the Golgi apparatus.
4. The Golgi apparatus modifies, sorts, and packages these molecules into vesicles.
5. Diagram: Draw a cell showing the nucleus, Rough ER with ribosomes, Smooth ER, Golgi apparatus, transport vesicles, and the plasma membrane with arrows indicating the pathway from ER to Golgi and then to the cell membrane.

**Answer:** Proteins and lipids are synthesized by the ER, packaged by the Golgi apparatus into vesicles, and transported to the cell membrane.

> Common mistake: Forgetting to mention that proteins are made on RER and lipids on SER.

### Question 15

*3 marks · Short answer*

What would happen if gametes are formed by mitotic divisions?

**Solution**

1. Mitosis is a type of cell division that produces two genetically identical daughter cells with the same number of chromosomes as the parent cell.
2. If gametes were formed by mitotic division instead of meiotic division, they would retain the full diploid set of chromosomes instead of being haploid.
3. When such gametes combine during fertilisation, the resulting offspring would have double the normal chromosome number, disrupting genetic stability.

**Answer:** If gametes were formed by mitosis, they would be diploid instead of haploid, leading to doubling of the chromosome number in successive generations after fertilisation.

> Common mistake: Confusing mitosis with meiosis and stating that chromosome number is halved.

### Question 16

*4 marks · Case-based*

A farmer, Deepa, was very happy with the harvest of amla (Indian Gooseberry) and lemons on her farm. However, she could sell only one-fourth of the produce in the local market. Recognising that a significant amount of produce may be lost post-harvest, she employed a traditional yet scientifically sound method to extend the shelf life of amla and lemons. She turned perishable produce into profitable products, such as pickles and sharbat. She used the excess produce to prepare pickles, murabbas, and sharbat by adding appropriate amounts of salt, sugar, or jaggery to small pieces of fruit and their juices. These were then stored in small glass bottles for sale, helping her prevent the wastage of post-harvest produce. This shift from farming to agro-processing would strengthen food security and boost the local economy, creating a sustainable model that cuts waste while increasing her income. Based on the above passage answer the following questions:
(i) Which scientific concept has the farmer applied in the preservation of the farm produce?
(ii) How does the addition of high concentrations of salt and sugar create an environment that prevents the growth of spoilage-causing bacteria and fungi?
(iii) Suggest a healthy recipe of this kind for food preservation.
(iv) What are the scientific values addressed in this case?

**Part (i)**

1. The farmer applied the scientific concepts of osmosis and prevention of microbial growth by increasing solute concentration.

Answer (i): Osmosis and high solute concentration for food preservation.

**Part (ii)**

1. High concentrations of salt and sugar create a hypertonic external environment around spoilage-causing bacteria and fungi.
2. Water moves out of the microbial cells due to osmosis, causing them to shrink, lose activity, and die.

Answer (ii): High salt and sugar create a hypertonic medium causing water to move out of microbial cells by osmosis, killing them.

**Part (iii)**

1. A healthy traditional recipe is amla murabba or low-sugar mixed fruit pickle prepared using natural preservatives like salt, turmeric, and edible oils.

Answer (iii): Amla murabba or home-made amla pickle.

**Part (iv)**

1. The scientific values addressed include resource management, reducing food waste, applying scientific knowledge to agro-processing, and promoting sustainable local economies.

Answer (iv): Reduction of food waste, sustainable agro-processing, and application of scientific knowledge to daily life.

**Answer:** The farmer applied the principle of osmosis and high solute concentration to prevent microbial growth and preserve food.

> Common mistake: Explaining preservation only as drying instead of linking it to osmosis and hypertonic concentration.

## Frequently asked questions

### How many total questions are included in the SwaVid NCERT solutions for Class 9 Science Chapter 2?

Our comprehensive page covers all questions from the new NCERT book for the 2026-27 session, including 4 Think It Over questions, 7 Pause and Ponder questions across multiple sections, and 16 Revise, Reflect, Refine questions. You can access step-by-step solutions for every single question right here on this page.

### Which specific topics are covered by the chapter questions?

The questions thoroughly explore vital concepts such as the cell as the structural and functional unit of life, cell division like mitosis versus meiosis, and cell organelles and their functions. Other key topics include osmosis in plant tissues, plastids, mitochondria, and technological interventions in microscopy.

### Which question types are the hardest and how should I approach them?

Case-based and long-answer questions in the Revise, Reflect, Refine section are often considered the most challenging by students. To score full marks, carefully analyze the given experimental scenarios like potato osmosis or tumor formation, and structure your answers by stating the biological principle first before explaining the cause and effect.

### How can I write answers to score full marks in Class 9 Science exams?

To secure full marks, ensure your answers use precise biological terminology related to cell structures, such as mentioning specific organelles or osmotic pressures where required. Following the structured explanations provided in SwaVid's solutions will help you present your answers clearly and logically.

### Is a free PDF of these solutions available for the 2026-27 session?

Yes, SwaVid provides a completely free PDF containing detailed step-by-step solutions for this chapter based on the new NCERT book under the NCF 2023 guidelines. You can easily download or view these resources directly on this page to aid your exam preparation.

## Related pages

- [Class 9 Science chapters](https://www.swavid.com/science/class/9)

Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student