Science
Plant hormones
पादप हार्मोन
In this Class 10 Science topic from the chapter Control and Coordination, students learn how plants coordinate growth and respond to their surroundings without a nervous system. The topic introduces plant hormones such as auxin, gibberellin, cytokinin, abscisic acid and ethylene, explaining their roles in cell growth, seed germination, flowering, dormancy, fruit ripening and leaf fall. Students also connect these chemical signals with responses such as phototropism and geotropism, building a clear understanding of plant regulation and movement.
Practice questions
Why can abscisic acid be called a stress hormone?MediumLevel 16If a plant receives light from one side, where can auxin mostly collect?MediumLevel 16Which plant hormone is associated with helping cell division?MediumLevel 17Which plant hormone is linked with growth inhibition and wilting of leaves?MediumLevel 17Which plant hormone helps in increasing stem length?MediumLevel 17If light falls on a plant stem from one side only then towards which side will the stem bend?MediumLevel 18What does positive geotropism in a plant root mean?EasyLevel 18Which plant structure can coil around a support after touching it?EasyLevel 18A plant stem is given light from one side and it bends towards the light. What is the correct reason for this bending?MediumLevel 16Why is phototropism in plants called a growth based response?MediumLevel 16If auxin distribution is artificially kept equal in a plant why may stem bending reduce even with one sided light?HardLevel 16Why is it suitable to understand abscisic acid as both a growth inhibitor and a stress hormone?HardLevel 16What conclusion about plant growth can be drawn by combining the functions of gibberellin and cytokinin?MediumLevel 16If stomata of a plant remain open during severe water shortage, which hormone may be deficient or ineffective?MediumLevel 16In which situation can hormonal control be considered more suitable than nervous control?MediumLevel 16Why can the same hormone have different effects in different parts of a plant?HardLevel 16A plant receives light from one side, but its shoot tip is covered. Why may bending of the stem decrease?MediumLevel 17Cells on the shaded side of a plant stem become more elongated. In which direction will the plant bend?MediumLevel 17High auxin concentration may inhibit growth in roots but promote growth in stems. What does this show?MediumLevel 17If the effect of cytokinin becomes very low, which plant function may be affected more?MediumLevel 17