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Class 9 Science Chapter 3 Important Questions and Answers PDF
Important Questions and Answers for Class 9 Science Exploration Chapter 3 – Tissues in Action | 2026–27
ShareShareThese important questions for Class 9 Chapter 3 Science help students understand how tissues support plant growth, body movement and coordination. The Class 9 Chapter 3 Science important questions include experiments, tissue identification, comparisons and application-based answers from Tissues in Action.
Multiple Choice Questions on Plant and Animal Tissues
Q1. A student observes that onion roots continue growing in Jar A, but show very little further lengthwise growth after their tips are removed in Jar B. Which tissue is mainly responsible for the difference?
(a) Lateral meristem
(b) Apical meristem
(c) Sclerenchyma
(d) Phloem
Answer: (b) Apical meristem.
Explanation: Apical meristematic tissue is present near the tips of roots and shoots. Its actively dividing cells contribute to growth in length. Removing the root tip removes or damages this growing region, so elongation is greatly reduced.
Q2. A lawn is mowed regularly, but its grass grows again from regions near the stem bases. Which tissue makes this possible?
(a) Intercalary meristem
(b) Xylem vessel
(c) Cork tissue
(d) Sclerenchyma fibre
Answer: (a) Intercalary meristem.
Explanation: Intercalary meristems are growing regions found near nodes or the bases of internodes in plants such as grasses. They allow continued growth after the upper parts have been removed by grazing or mowing.
Q3. A flexible coriander leaf stalk bends without breaking, while a hard coconut husk resists bending. Which tissue pair best explains this difference?
(a) Phloem and xylem
(b) Collenchyma and sclerenchyma
(c) Epidermis and parenchyma
(d) Meristem and nervous tissue
Answer: (b) Collenchyma and sclerenchyma.
Explanation: Collenchyma provides flexible support because its living cells have unevenly thickened walls. Sclerenchyma provides rigidity through thick, lignified walls and is commonly found in hard plant structures.
Q4. A person twists the head gently from side to side to indicate 'no'. Which joint mainly allows this movement?
(a) Fixed joint
(b) Hinge joint
(c) Pivot joint
(d) Ball-and-socket joint
Answer: (c) Pivot joint.
Explanation: A pivot joint in the upper neck allows the head to rotate from side to side. Hinge joints mainly permit bending and straightening, while ball-and-socket joints allow movement in several directions.
Q5. Which structure connects a skeletal muscle to a bone and transmits the pulling force during movement?
(a) Ligament
(b) Tendon
(c) Cartilage
(d) Plasma
Answer: (b) Tendon.
Explanation: Tendons connect muscles to bones. When muscles contract, tendons transmit the force to the bones, moving joints. Ligaments connect bone to bone and provide joint stability.
Q6. Assertion–Reason:
Assertion (A): Xylem can transport water even though its main conducting cells are dead at maturity.
Reason (R): Xylem vessels and tracheids form continuous pathways through which water can move.
(a) Both A and R are true, and R correctly explains A.
(b) Both A and R are true, but R does not explain A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Answer: (a) Both A and R are true, and R correctly explains A.
Explanation: Mature xylem vessels and tracheids form conducting pathways. Water movement is supported by processes such as transpiration pull, cohesion and adhesion. The cells do not need to remain alive to function as water-conducting tubes.
Very Short Answer Questions on Tissue Functions
Q7. What is meant by the division of labour in multicellular organisms?
Answer: Division of labour means different groups of cells perform specialised functions. For example, muscle tissue moves, nervous tissue carries signals and blood transports materials. This makes the organism more efficient.
Q8. Which meristem increases the thickness or girth of a woody stem?
Answer: The lateral meristem, especially the vascular cambium, contributes to the increase in stem girth through the formation of new tissues.
Q9. Why are meristematic cells generally small and closely packed?
Answer: Meristematic cells divide actively. They typically have thin cell walls, dense cytoplasm, prominent nuclei and very little intercellular space, supporting rapid cell division and growth.
Q10. What is the function of companion cells in phloem?
Answer: Companion cells support sieve-tube elements and help regulate the loading and unloading of sugars during food transport.
Q11. Why is blood classified as connective tissue even though it is a liquid?
Answer: Blood transports gases, nutrients, hormones and other substances between different parts of the body. Its cells are suspended in a fluid matrix called plasma, making it a specialised connective tissue.
Short Answer Questions on Growth, Transport and Body Movement
Q12. A student records the following root-growth data in two jars. In Jar B, 1 cm of each onion root tip was removed after Day 3. Interpret the results and identify the growing tissue.
Answer:
The roots in Jar A continue growing because their apical meristems remain intact.
In Jar B, removing approximately 1 cm of the root tips reduces the recorded length from 2.6 cm to 1.6 cm.
The roots then show no further lengthwise growth in the given observations.
Conclusion: The apical meristem near the root tip is responsible for the production of new cells that contribute to root elongation.
Q13. A tree trunk shows alternating wide and narrow annual growth rings. What information can these rings provide, and why do they form?
Answer:
Annual growth rings are formed through the activity of the lateral meristem, particularly the vascular cambium.
The cambium produces new secondary tissues, increasing the girth of the tree.
In trees that form distinct annual rings, each ring often represents one growing season.
Wide rings may indicate comparatively favourable growing conditions.
Narrow rings may indicate limited growth because of factors such as drought or other stresses.
Counting rings can help estimate the age of the tree.
Important Point: Ring width is influenced by several factors, including water availability, temperature, competition and the species of tree.
Q14. Why does a cactus have a thick cuticle, while many submerged aquatic plants do not require a similarly thick protective layer?
Answer:
A cactus grows in dry conditions where conserving water is important.
Its thick, waxy cuticle reduces water loss from the plant surface.
A submerged aquatic plant remains surrounded by water, so protection against excessive evaporation is usually less important.
A thick cuticle may also make the exchange of substances with surrounding water more difficult.
Conclusion: The structure of protective tissues changes according to the environment in which a plant lives.
Q15. Explain why parenchyma, collenchyma and sclerenchyma are called simple permanent tissues. Compare their main functions.
Answer:
They are called simple permanent tissues because each consists mainly of one kind of specialised cell.
Examples:
Parenchyma can store food in plant tissues.
Collenchyma helps young stems and leaf stalks bend without breaking.
Sclerenchyma gives strength to coconut husks and hard seed coverings.
Q16. A plant absorbs sufficient water through its roots, but a blockage develops in the conducting tissues of its stem. How would damage to xylem differ from damage to phloem?
Answer:
Xylem and phloem are complex permanent tissues with different transport functions.
Xylem Damage:
Reduces the movement of water and minerals from roots towards leaves.
May cause wilting and reduced photosynthesis.
Can affect support and normal growth.
Phloem Damage:
Interrupts the transport of sugars from sources such as leaves to regions that need or store food.
May affect roots, growing shoots and developing fruits.
Can weaken the plant even when water absorption continues.
Conclusion: Healthy plants require both xylem and phloem because water transport and food transport are different but connected processes.
Q17. Why does the small intestine have an epithelial lining suited for absorption, while the outer skin has many protective layers?
Answer:
Tissues are adapted to perform their functions.
The small intestine contains epithelial cells specialised for absorbing nutrients.
Its lining has structures such as microvilli that increase the available surface area for absorption.
The outer skin contains multiple layers of epithelial cells that protect underlying tissues against friction, injury and microorganisms.
Comparison:
Conclusion: Different epithelial structures help body surfaces perform different tasks efficiently.
Q18. A child falls while playing and experiences pain near the knee. Explain the functions of bone, cartilage, ligaments and tendons at a movable joint.
Answer:
These structures work together to support movement and stability.
Bone: Provides rigid support and forms the framework of the joint.
Cartilage: Covers relevant joint surfaces, reducing friction and cushioning movement.
Ligament: Connects bone to bone and helps stabilise the joint.
Tendon: Connects muscle to bone and transmits force during movement.
A knee injury may involve one or several of these structures.
Conclusion: A joint works effectively because strong supporting structures and flexible connective tissues cooperate.
Q19. Compare skeletal, smooth and cardiac muscles using their structure, location and control.
Answer:
Explanation:
Skeletal muscles help us walk, write and lift objects.
Smooth muscles help move food through the digestive tract.
Cardiac muscles contract rhythmically to keep blood circulating.
Conclusion: All three produce movement, but their structures and control mechanisms suit different functions.
Long Answer and Application-Based Questions on Tissues in Action
Q20. Explain how three types of meristematic tissues support different patterns of plant growth. Include a suitable labelled diagram.
Answer:
Meristematic tissues contain cells that divide actively to produce new plant cells.
Different meristems occur in different regions of the plant.
1. Apical Meristem
Location: Near the tips of roots and shoots.
Function: Produces new cells that contribute to growth in length.
Example: The roots of a germinating onion bulb grow longer through activity in the root-tip region.
2. Lateral Meristem
Location: Along the sides of stems and roots, including the cambium in woody plants.
Function: Produces new cells that increase girth.
Example: A tree trunk becomes thicker as secondary tissues accumulate.
3. Intercalary Meristem
Location: Near nodes or the bases of internodes in certain plants, especially grasses.
Function: Allows elongation and regrowth even after upper portions have been removed.
Example: Grass regrows after mowing.
Comparison Table:
Importance of Meristematic Cells
These cells generally have dense cytoplasm, prominent nuclei and thin cell walls.
Their continuous division allows plants to grow throughout much of their lives.
Conclusion: Apical, lateral and intercalary meristems allow plants to grow in length, increase thickness and recover from cutting or grazing.
Q21. Describe how the three plant tissue systems work together in a sunflower stem.
Answer:
Plant tissues are organised into systems that perform protection, support, storage and transport.
1. Dermal Tissue System
The dermal system forms the outer covering.
The epidermis protects the plant from injury and microorganisms.
The cuticle helps reduce water loss.
Stomata in appropriate regions allow gas exchange and contribute to transpiration.
2. Ground Tissue System
The ground system occupies much of the plant body between the outer covering and vascular tissues.
It includes:
Parenchyma for storage and other metabolic functions.
Collenchyma for flexible support.
Sclerenchyma for strength and rigidity.
3. Vascular Tissue System
The vascular system contains xylem and phloem.
Xylem: Transports water and dissolved minerals from roots to other plant parts.
Phloem: Transports sugars and other organic substances from sources to regions where they are needed.
How They Work Together
A sunflower stem remains upright through supporting tissues.
Its epidermis protects it.
Xylem supplies water to leaves.
Phloem transports sugars produced through photosynthesis.
Conclusion: A plant survives because its protective, supporting and conducting tissues function as coordinated systems.
Q22. Explain how epithelial, connective, muscular and nervous tissues cooperate when a person touches a hot object and quickly withdraws the hand.
Answer:
A rapid response to heat requires coordination among several tissues.
Step 1: Sensory Detection
Sensory receptors in the skin detect the potentially harmful heat.
Step 2: Signal Transmission
Sensory neurons transmit nerve impulses towards the spinal cord.
Step 3: Processing
The nervous system processes the signal and can trigger a rapid withdrawal reflex.
Step 4: Motor Signal
Motor neurons send impulses to muscles responsible for moving the hand.
Step 5: Muscle Contraction
Skeletal muscles contract and pull on bones through tendons.
Step 6: Joint Movement
Bones move at the relevant joints, allowing the hand to move away.
7. Role of Protective and Connective Tissues
Epithelial tissue helps protect the body surface.
Connective tissues such as bone, tendons and ligaments support movement and stability.
Conclusion: A single action requires different tissues to work together. This demonstrates division of labour at the tissue and organ-system levels.
Q23. Study the illustrations of the shoulder, elbow, neck and skull. Identify the type of joint in each and explain why the range of movement differs.
Answer:
Different joints provide different combinations of movement and stability.
1. Shoulder – Ball-and-Socket Joint
A rounded bone end fits into a socket.
It allows movement in several directions, including rotation.
This makes reaching, lifting and circular arm movements possible.
2. Elbow – Hinge Joint
The joint mainly permits bending and straightening.
Its structure limits sideways movement and provides stability.
3. Upper Neck – Pivot Joint
The joint arrangement between the first two cervical vertebrae allows the head to turn from side to side.
This movement is used when shaking the head to indicate 'no'.
4. Skull – Fixed Joints
Most skull bones are connected through immovable joints called sutures.
They protect the brain by forming a strong and stable covering.
Comparison Table:
Conclusion: Joint structure determines the range of motion while balancing mobility and protection.
Q24. Explain how tissue culture and totipotency help scientists produce whole plants from small tissue samples. Include the contributions of Indian researchers.
Answer:
Plant tissue culture is a method of growing plant cells or tissues under controlled laboratory conditions.
The technique is based partly on the ability of some plant cells to regenerate a complete plant under suitable conditions.
This developmental potential is associated with totipotency.
1. Selecting Plant Tissue
A suitable sample, called an explant, is collected from a healthy plant.
2. Preparing a Sterile Medium
The tissue is placed on a nutrient medium containing suitable minerals, sugars and growth regulators.
3. Cell Division and Development
Under controlled conditions, cells may multiply and form new tissues.
Depending on the method, shoots, roots or embryos can develop.
4. Regeneration of a Plantlet
A small plant develops with its own shoot and root system.
5. Transfer to Soil
The young plant is gradually adjusted to external conditions and transferred to a suitable growing medium.
Applications
Multiplying selected crop varieties.
Producing large numbers of plants.
Supporting crop improvement.
Conserving valuable plant material.
Indian Scientific Contributions
Professors Sipra Guha Mukherjee and S. C. Maheshwari made important contributions to plant tissue culture.
Their work on anther culture demonstrated the development of plants from reproductive tissue under laboratory conditions.
This research helped advance plant breeding and agricultural biotechnology.
Conclusion: Tissue culture demonstrates how specialised scientific techniques can use the developmental potential of plant cells for agriculture and research.
Important Concepts, Diagrams and Preparation Tips for Class 9 Science Chapter 3
The Chapter 3 Science Class 9 important questions cover plant and animal tissues, their functions and how they work together. Along with these Science Chapter 3 Class 9 important questions, revise the following concepts using practical examples and labelled diagrams.
Preparation Tips: Practise tissue identification, compare structures and functions, interpret the onion-root experiment, and explain how muscles, bones and nerves coordinate movement. Use labelled diagrams and everyday examples to support your answers.
The Class 9 Science Chapter 3 Important Questions PDF, once available, can help students revise solved questions, experiments, diagrams and comparisons from Tissues in Action for the 2026–27 academic session.
Additional Study Materials for Class 9 Science Chapter 3 – Tissues in Action
CBSE Class 9 Science Chapter-wise Important Questions
These chapter-wise resources help students strengthen their understanding of concepts from the Exploration Science textbook for the 2026–27 academic session.
Other Important Related Links for CBSE Class 9 Science
FAQs on Important Questions and Answers for Class 9 Science Exploration Chapter 3 – Tissues in Action | 2026–27
1. Why do multicellular organisms need tissues instead of using every cell for every function?
Multicellular organisms perform many complex activities simultaneously. Different cells specialise in functions such as protection, movement, transport and communication. When similar cells work together as tissues, these functions can be performed more efficiently. This arrangement is called division of labour.
2. Why do neurons have long extensions called axons?
Neurons have specialised extensions that help carry nerve impulses between different parts of the body. Axons carry signals away from the cell body towards other neurons, muscles or glands. This allows the nervous system to coordinate movement, sensation and responses to changes in the surroundings.
3. How can annual growth rings in a tree reveal information about earlier growing conditions?
Annual rings form as a result of secondary growth in many woody trees. Ring width can vary with environmental conditions. Wider rings may indicate favourable growth during a particular season, while narrow rings may reflect stress such as drought. Scientists examine ring patterns to study tree age and past environmental conditions.
4. Why does cartilage heal more slowly than many other body tissues?
Cartilage has a limited blood supply, and its cells receive nutrients mainly through diffusion. As a result, damaged cartilage generally repairs more slowly than tissues with a richer blood supply. This is why cartilage injuries may require more time to heal.
5. How are permanent tissues different from meristematic tissues in plants?
Meristematic tissues contain actively dividing cells responsible for plant growth. Permanent tissues generally contain cells that have differentiated to perform specialised tasks such as storage, transport, protection or support. Some permanent tissue cells can regain the ability to divide under particular conditions, but active division is not their usual function.
6. Why do plant roots have root hairs, and why do leaves have stomata?
Root hairs are extensions of epidermal cells that increase the surface area available for absorbing water and minerals from soil. Stomata are pores that allow gas exchange between leaves and the atmosphere. They also permit water vapour to leave during transpiration.
7. What makes xylem and phloem complex permanent tissues?
Xylem and phloem each contain several types of cells working together. Xylem includes vessels, tracheids, fibres and parenchyma. Phloem includes sieve-tube elements, companion cells, fibres and parenchyma. Their combined organisation allows efficient transport and support.
8. Why do blood and bone both belong to connective tissue despite looking completely different?
Both support the body's organisation by connecting or supporting other parts. Blood contains cells suspended in a fluid matrix and transports substances. Bone contains cells within a hard, mineral-rich matrix and provides support and protection. Their different matrices explain their very different physical properties.
9. Why are platelets important when someone gets a small cut?
Platelets help initiate the blood-clotting process when a blood vessel is damaged. They gather at the injury site and work with clotting factors to form a clot. This helps reduce blood loss and supports the beginning of tissue repair.
10. Why are skeletal muscles voluntary while smooth and cardiac muscles are involuntary?
Skeletal muscles are generally controlled through conscious motor actions such as walking or writing. Smooth muscles in organs and cardiac muscles in the heart operate mainly through automatic control systems. Cardiac muscle also has specialised cells that help generate rhythmic contractions.
11. Why can a ligament injury make a joint unstable even when the bones are not broken?
Ligaments connect bones to other bones and help limit excessive joint movement. When a ligament is overstretched or torn, it may no longer stabilise the joint effectively. This can cause pain, swelling and abnormal movement even without a bone fracture.
12. How can yoga, exercise and proper posture support the musculoskeletal system?
Appropriate physical activity helps maintain muscle strength, joint mobility and balance. Good posture reduces unnecessary strain on the muscles and supporting structures. Yoga may support flexibility, body awareness and controlled movement when practised safely. Proper nutrition and adequate recovery are also important for musculoskeletal health.
13. What is totipotency, and why is it useful in plant tissue culture?
Totipotency is the developmental potential of a cell to give rise to a complete organism under suitable conditions. Certain plant cells can be encouraged to regenerate whole plants using controlled culture techniques. This makes tissue culture valuable for plant propagation, crop improvement and scientific research.
14. Where can students find Science Class 9 Chapter 3 important questions with answers for 2026–27?
Students can practise solved MCQs, experiments and diagram-based questions on Vedantu. The questions cover plant and animal tissues, muscles, joints and tissue culture. Students can also use the Class 9 Chapter 3 important questions Science material for revision and practice related topics before exams.
