1. The correct answer is (ii) hinge joint. Hinge joints permit movement mainly in one plane, allowing bending and straightening actions. The knee and ankle joints work like door hinges, providing controlled movement and stability. These joints help in activities such as walking, running, jumping and maRead more

    The correct answer is (ii) hinge joint. Hinge joints permit movement mainly in one plane, allowing bending and straightening actions. The knee and ankle joints work like door hinges, providing controlled movement and stability. These joints help in activities such as walking, running, jumping and maintaining posture while limiting unnecessary sideways movements that could cause injury.

     

    For more NCERT Solutions of Class 9 Science Exploration Chapter 3 Tissues in Action Question Answer (2026-27)

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  2. A.(iii) Epithelium supports gas exchange, but lungs have thin simple epithelium, not multiple tall layers. B. (i) Cardiac muscles resist fatigue because of many mitochondria and rich blood supply. C. (iv) Tendons connect muscles to bones, not bones to bones. D. (iii) Hinge joints move mainly in oneRead more

    A.(iii) Epithelium supports gas exchange, but lungs have thin simple epithelium, not multiple tall layers.
    B. (i) Cardiac muscles resist fatigue because of many mitochondria and rich blood supply.
    C. (iv) Tendons connect muscles to bones, not bones to bones.
    D. (iii) Hinge joints move mainly in one plane, but they do not allow sliding in all directions like ball and socket joints.

     

    For more NCERT Solutions of Class 9 Science Exploration Chapter 3 Tissues in Action Question Answer (2026-27)

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  3. The incorrect match is (ii) SER — Lipid and cellulose synthesis. Smooth endoplasmic reticulum synthesises lipids but does not produce cellulose. Ribosomes correctly perform protein synthesis and lysosomes digest foreign substances and wastes. Therefore, option (ii) is incorrect, while the other pairRead more

    The incorrect match is (ii) SER — Lipid and cellulose synthesis. Smooth endoplasmic reticulum synthesises lipids but does not produce cellulose. Ribosomes correctly perform protein synthesis and lysosomes digest foreign substances and wastes. Therefore, option (ii) is incorrect, while the other pairs are correctly matched with their functions.

     

    For more NCERT Solutions of Class 9 Science Exploration Chapter 2 Cell: The Building Block of Life (2026-27)

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  4. (i) The hypothesis is that osmosis causes water movement in cells. (ii) Use equal-sized carrots, measure initial and final weight and repeat trials for accuracy. (iii) In plain water, carrot cells gain water and become stiff due to turgor pressure. In salt solution, water leaves cells, causing themRead more

    (i) The hypothesis is that osmosis causes water movement in cells.
    (ii) Use equal-sized carrots, measure initial and final weight and repeat trials for accuracy.
    (iii) In plain water, carrot cells gain water and become stiff due to turgor pressure. In salt solution, water leaves cells, causing them to shrink and become soft and limp.

     

    For more NCERT Solutions of Class 9 Science Exploration Chapter 2 Cell: The Building Block of Life (2026-27)

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  5. The correct answer is (ii) Mitochondria and Nucleus. Both these organelles contain their own DNA. The nucleus stores most genetic information, while mitochondria have their own small circular DNA. Ribosomes, Golgi bodies and lysosomes do not contain DNA. Therefore, option (ii) correctly identifies oRead more

    The correct answer is (ii) Mitochondria and Nucleus. Both these organelles contain their own DNA. The nucleus stores most genetic information, while mitochondria have their own small circular DNA. Ribosomes, Golgi bodies and lysosomes do not contain DNA. Therefore, option (ii) correctly identifies organelles that possess genetic material.

     

    For more NCERT Solutions of Class 9 Science Exploration Chapter 2 Cell: The Building Block of Life (2026-27)

    https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-2/

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