CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02

Multiple Choice Questions (MCQs) for Class 9 Science: Chapter 01 Exploration Entering The World Of Secondary Science

Access targeted multiple-choice questions for Chapter 01 Exploration Entering The World Of Secondary Science designed to align with the latest CBSE academic syllabus for Class 9 Science. These objective practice sets help students evaluate their conceptual understanding and improve exam readiness.

Practice Chapter 01 Exploration Entering The World Of Secondary Science MCQs for Class 9 Science

Access the complete set of multiple-choice questions for Chapter 01 Exploration Entering The World Of Secondary Science below. This focused format allows students to isolate specific topics for thorough review and uninterrupted practice alongside official CBSE textbooks.

Question: Why is cellulose from plant cell walls considered beneficial in the human diet even though our bodies cannot digest it?
A. It acts as roughage that aids digestion
B. It gets converted into glucose for quick energy
C. It strengthens bones by mimicking calcium
D. It kills harmful bacteria in the gut
Show Answer & Explanation

Answer: (A) It acts as roughage that aids digestion

Explanation:
Cellulose passes through our digestive system largely undigested, and the chapter notes that this fibrous material functions as roughage, which supports healthy digestion.

Question: The plant cell wall, which gives rigidity and helps the plant remain upright, is mainly built from which substance?
A. A carbohydrate made of linked glucose units called cellulose
B. A protein similar to those in the cell membrane
C. A fat molecule similar to those in the lipid bilayer
D. Calcium carbonate deposits
Show Answer & Explanation

Answer: (A) A carbohydrate made of linked glucose units called cellulose

Explanation:
Cellulose, formed by many glucose molecules joined together, makes up the bulk of the plant cell wall and gives it structural strength.

Question: Fruits and flower petals often display bright yellow, orange or red shades. Which cell structures are responsible for these colours?
A. Chromoplasts
B. Leucoplasts
C. Chloroplasts
D. Lysosomes
Show Answer & Explanation

Answer: (A) Chromoplasts

Explanation:
Pigments other than chlorophyll are held in chromoplasts, giving petals and fruits their vivid colours, which in turn attract pollinators and animals that disperse seeds.

Question: Potato tubers and taro corms store starch inside colourless plastids. What term describes these particular plastids?
A. Leucoplasts
B. Chromoplasts
C. Chloroplasts
D. Ribosomes
Show Answer & Explanation

Answer: (A) Leucoplasts

Explanation:
Since these plastids lack any pigment, they appear colourless and are called leucoplasts; they specialise in storing food such as starch, oils or proteins.

Question: In most animal tissues, cell division stops once dividing cells touch their neighbours on all sides. What is this regulatory phenomenon called?
A. Contact inhibition
B. Programmed cell death
C. Cellular respiration
D. Totipotency
Show Answer & Explanation

Answer: (A) Contact inhibition

Explanation:
Contact inhibition keeps normal cell division in check by halting further division once cells make contact with surrounding cells, preventing unchecked growth.

Question: Cancer cells behave abnormally compared to normal body cells. What specifically goes wrong in cancer cells that leads to tumour formation?
A. They lose the ability to stop dividing when in contact with neighbouring cells
B. They stop producing ATP entirely
C. They lose their cell membrane completely
D. They convert into prokaryotic cells
Show Answer & Explanation

Answer: (A) They lose the ability to stop dividing when in contact with neighbouring cells

Explanation:
• Normal cells respect contact inhibition and stop dividing once surrounded by neighbours
• Cancer cells ignore this signal and keep dividing without control
• This uncontrolled division results in the formation of tumours, which may spread to other tissues

Question: During the development of a human embryo, some cells between the developing fingers are deliberately eliminated so that the fingers separate instead of remaining webbed. Which process brings this about?
A. Programmed cell death
B. Mitosis
C. Contact inhibition
D. Osmosis
Show Answer & Explanation

Answer: (A) Programmed cell death

Explanation:
This controlled, genetically regulated elimination of specific cells is called programmed cell death, and the chapter gives finger separation during embryonic development as an example of its role.

Question: Scientists often grow cells outside a living organism in a nutrient-rich medium under carefully controlled temperature and sterile conditions. What is this technique called?
A. Cell culture
B. Cell theory
C. Cell division
D. Cell inclusion
Show Answer & Explanation

Answer: (A) Cell culture

Explanation:
This method, called cell culture, allows cells taken from an organism to grow and multiply outside the body, and it is widely used to study cell behaviour and to manufacture medicines and vaccines.

Question: DNA molecules inside chromosomes carry hereditary information, but only certain stretches of this DNA actually code for traits. What are these functional stretches called?
A. Genes
B. Nucleoids
C. Chromatins
D. Cristae
Show Answer & Explanation

Answer: (A) Genes

Explanation:
Not all of the DNA in a chromosome is functional in the same way — the specific segments that carry usable genetic instructions are known as genes.

Question: Human sperm cells carry a particular organelle whose enzymes help break down the outer covering of the egg during fertilisation. Which organelle is this?
A. Lysosome
B. Golgi apparatus
C. Mitochondrion
D. Ribosome
Show Answer & Explanation

Answer: (A) Lysosome

Explanation:
Lysosomes are packed with digestive enzymes, and in sperm cells these enzymes are put to a special use — dissolving the egg's outer layer so fertilisation can proceed.

Question: The inner membrane of a mitochondrion is folded into finger-like structures rather than remaining flat. What advantage does this folding provide?
A. It increases the surface area available for energy-releasing reactions
B. It allows the mitochondrion to store starch
C. It helps the organelle change its own DNA
D. It prevents ribosomes from attaching to it
Show Answer & Explanation

Answer: (A) It increases the surface area available for energy-releasing reactions

Explanation:
These folds, called cristae, expand the inner membrane's surface area, allowing more chemical reactions related to energy production to occur within the same small space.

Question: Cellular respiration inside mitochondria breaks down glucose and releases energy, which is then stored in a specific molecule used across the cell for various activities. What is this molecule called?
A. Adenosine Triphosphate (ATP)
B. Deoxyribonucleic acid (DNA)
C. Chlorophyll
D. Cellulose
Show Answer & Explanation

Answer: (A) Adenosine Triphosphate (ATP)

Explanation:
The chapter describes ATP as the cell's energy currency, meaning the energy captured during respiration is stored in ATP and then spent to power different cellular tasks.

Question: An Indian botanist known for developing important laboratory techniques to study plant chromosomes was honoured with the Padma Bhushan for his contributions. Who was this scientist?
A. Arun Kumar Sharma
B. J. Craig Venter
C. Camillo Golgi
D. Gottlieb Haberlandt
Show Answer & Explanation

Answer: (A) Arun Kumar Sharma

Explanation:
Arun Kumar Sharma, a botanist recognised for his research on plant taxonomy, evolution and chromosome study methods, received both the Shanti Swarup Bhatnagar award and the Padma Bhushan for his work.

Question: In male animals, including humans, meiosis takes place specifically in which organ to produce gametes?
A. Testes
B. Kidneys
C. Liver
D. Anthers
Show Answer & Explanation

Answer: (A) Testes

Explanation:
Meiosis in male animals occurs in the testes to form sperm, while the corresponding process in females occurs in the ovaries; anthers are where meiosis happens in plants, not animals.

Question: The formulation of the Cell Theory drew on findings from more than one scientist studying different groups of organisms. What was the overall significance of this combined work?
A. It established that all living things, from bacteria to humans, share the cell as their basic structural and functional unit
B. It proved that only plants are made of cells
C. It showed that animal cells lack a nucleus
D. It disproved that cells arise from pre-existing cells
Show Answer & Explanation

Answer: (A) It established that all living things, from bacteria to humans, share the cell as their basic structural and functional unit

Explanation:
By combining Schleiden's work on plants, Schwann's work on animals, and Virchow's idea that cells arise only from existing cells, the Cell Theory unified biology around the concept that the cell is the fundamental unit of life across all organisms.

Question: The fluid-mosaic model describes the cell membrane as 'fluid'. What does this term specifically indicate about the membrane?
A. The membrane is made entirely of water molecules
B. Lipid and protein molecules can move sideways, flip and rotate within the membrane
C. The membrane dissolves easily in water
D. The membrane constantly changes its total surface area
Show Answer & Explanation

Answer: (B) Lipid and protein molecules can move sideways, flip and rotate within the membrane

Explanation:
Fluidity refers to the movement of the lipid and protein molecules within the two layers of the membrane, not to any liquid composition. This mobility lets the membrane remain flexible while still forming a continuous barrier.

Question: What role does the cytoskeleton play inside a eukaryotic cell?
A. It stores starch and mineral crystals
B. It synthesises ribosomal subunits
C. It gives structural support, maintains shape, and assists in movement and internal transport
D. It produces ATP through cellular respiration
Show Answer & Explanation

Answer: (C) It gives structural support, maintains shape, and assists in movement and internal transport

Explanation:
The cytoskeleton is a network of fine fibres spread through the cytoplasm.
• It maintains the shape of the cell
• It provides mechanical support
• It helps in movement and moving materials inside the cell
It is visible as a distinct structure only under an electron microscope.

Question: Although the plant cell wall is rigid, it still allows water and dissolved minerals to pass through it. What benefit does this provide to the plant?
A. It prevents any water from entering root cells
B. It works with the selectively permeable cell membrane so that roots can absorb water and nutrients from soil
C. It allows the cell wall to change shape freely like the cell membrane
D. It stops osmosis from occurring in plant cells
Show Answer & Explanation

Answer: (B) It works with the selectively permeable cell membrane so that roots can absorb water and nutrients from soil

Explanation:
Rigidity and permeability are not contradictory here — the wall stays firm in shape while still letting water and minerals through. Combined with the selective permeability of the underlying membrane, this partnership is what allows roots to draw up water and nutrients from the soil.

Question: How is the genetic material arranged inside a typical bacterial cell?
A. As multiple chromosomes enclosed within a nuclear membrane
B. As a single circular DNA molecule associated with proteins, located in a region called the nucleoid
C. As linear DNA strands scattered freely without any associated proteins
D. As DNA packed inside a membrane-bound organelle called the nucleus
Show Answer & Explanation

Answer: (B) As a single circular DNA molecule associated with proteins, located in a region called the nucleoid

Explanation:
Bacteria are prokaryotes and therefore lack a membrane-bound nucleus. Instead, their single circular DNA molecule, bound with specific proteins, occupies an unenclosed region of the cytoplasm called the nucleoid.

Question: Among acellular infectious agents mentioned in the chapter, what structurally sets viruses apart from viroids?
A. Viruses have a protein coat around their genetic material, while viroids lack this coat
B. Viroids contain a protein coat but no genetic material at all
C. Viruses lack any genetic material whereas viroids are made only of protein
D. Viruses and viroids are identical in structure but differ only in size
Show Answer & Explanation

Answer: (A) Viruses have a protein coat around their genetic material, while viroids lack this coat

Explanation:
Both are far smaller than what a light microscope can reveal and lack true cells, but their construction differs: a virus wraps its genetic material in a protective protein coat, whereas a viroid is bare genetic material without any such covering.

Question: Based on how the chapter describes the organisation of the respiratory system, what is the correct order of biological organisation from the smallest to the largest level?
A. Organ system → organ → tissue → cell
B. Cell → tissue → organ → organ system
C. Tissue → cell → organ system → organ
D. Organ → tissue → organ system → cell
Show Answer & Explanation

Answer: (B) Cell → tissue → organ → organ system

Explanation:
Similar cells performing the same job group together to form a tissue; different tissues combine to build an organ, and several organs cooperating form an organ system — as seen when the nasal passage, trachea and lungs together make up the respiratory system.

Question: In the potato osmosis experiment, why is it important to cut both potato pieces to roughly the same size and record their weights before placing them in different liquids?
A. So that any change in weight afterwards can be fairly attributed to the liquid's effect rather than to differences in starting size
B. Because unequal pieces would float differently in the beakers
C. So that both pieces absorb stain evenly during observation
D. Because larger pieces cannot undergo osmosis at all
Show Answer & Explanation

Answer: (A) So that any change in weight afterwards can be fairly attributed to the liquid's effect rather than to differences in starting size

Explanation:
If the two pieces started out at very different sizes or weights, any swelling or shrinking observed afterward could simply reflect that initial mismatch rather than the effect of the solution. Keeping the starting conditions equal makes the comparison between the water and salt-solution results meaningful.

Question: Some plant cells store extra substances such as starch grains or crystals of calcium oxalate directly within their cytoplasm rather than inside a membrane-bound organelle. What does the chapter call these stored materials?
A. Cell inclusions
B. Chromatin fibres
C. Cytoskeletal filaments
D. Nucleoid material
Show Answer & Explanation

Answer: (A) Cell inclusions

Explanation:
The chapter notes that besides organelles, the cytoplasm of plant cells may hold starch or crystals of calcium oxalate and silica, and these deposits are referred to as cell inclusions rather than true organelles.

Question: Why are plant roots able to efficiently take up water and dissolved minerals from the surrounding soil?
A. Because the permeable cell wall lets substances through while the selectively permeable cell membrane regulates what enters the cell
B. Because root cells lack a cell membrane entirely, allowing free entry of all substances
C. Because mitochondria in root cells actively pump water inward using ATP
D. Because the rigid cell wall alone decides exactly which minerals may enter the cell
Show Answer & Explanation

Answer: (A) Because the permeable cell wall lets substances through while the selectively permeable cell membrane regulates what enters the cell

Explanation:
Root cells rely on two layers working together: the cell wall, though rigid, still permits water and some dissolved minerals to pass through it, while the cell membrane beneath it selectively controls which of these substances actually move into the cell. This combined permeability, described in the chapter, is what makes efficient water and mineral absorption possible.

Question: Based on the diagram showing how proteins are processed and released from a cell, which sequence correctly represents the pathway from synthesis to secretion?
A. Ribosome forms protein, protein enters rough endoplasmic reticulum, moves to Golgi apparatus, then leaves in a vesicle through the plasma membrane
B. Golgi apparatus forms protein, sends it to ribosome, then to the nucleus for release
C. Protein is made in the vacuole, passed to lysosome, and released through the cell wall
D. Smooth endoplasmic reticulum forms protein, sends it directly to the nucleus, then out through nuclear pores
Show Answer & Explanation

Answer: (A) Ribosome forms protein, protein enters rough endoplasmic reticulum, moves to Golgi apparatus, then leaves in a vesicle through the plasma membrane

Explanation:
• Ribosomes attached to the rough ER synthesise the protein
• The RER passes it along to the Golgi apparatus for modification, sorting and packaging
• The Golgi apparatus packs it into a vesicle, which then travels to and fuses with the plasma membrane for secretion outside the cell

Free study material for Science

Chapter 01 Exploration Entering The World Of Secondary Science Objective Questions & Solutions for Class 9 Science

Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science Objective Test Questions

Test your conceptual understanding of Chapter 01 Exploration Entering The World Of Secondary Science with these targeted multiple-choice questions. Designed in alignment with the latest CBSE curriculum for Class 9 Science, these problem sets build accuracy and prepare students for objective exams.

NCERT-Aligned Objective Questions and Solutions

Cross-reference your completed choices with comprehensive NCERT solutions for Class 9 Science to ensure absolute clarity across all sub-topics in this chapter.

Next Steps in Your Exam Preparation

Follow up your worksheet practice by attempting the interactive online Science MCQ test for this chapter to evaluate your execution speed. All platform resources are free to access.

FAQs

Where can I access latest CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02?

You can get most exhaustive CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02 for free on StudiesToday.com. These MCQs for Class 9 Science are updated for the 2026-27 academic session as per CBSE examination standards.

Are Assertion-Reasoning and Case-Study MCQs included in the Science Class 9 material?

Yes, our CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02 include the latest type of questions, such as Assertion-Reasoning and Case-based MCQs. 50% of the CBSE paper is now competency-based.

How do practicing Science MCQs help in scoring full marks in Class 9 exams?

By solving our CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02, Class 9 students can improve their accuracy and speed which is important as objective questions provide a chance to secure 100% marks in the Science.

Do you provide answers and explanations for CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02?

Yes, Science MCQs for Class 9 have answer key and brief explanations to help students understand logic behind the correct option as its important for 2026 competency-focused CBSE exams.

Can I practice these Science Class 9 MCQs online?

Yes, you can also access online interactive tests for CBSE Class 9 Science Chapter 01 Exploration Entering The World Of Secondary Science MCQs Set 02 on StudiesToday.com as they provide instant answers and score to help you track your progress in Science.