Chapter 22, Problem 38A

Summary Introduction

To write: Seeds soaked in gibberellins will germinate faster than seeds not soaked in gibberellins.

Introduction: The roots heading down in plants, the branches rising upward, the trees lowering their leaves and the leaves of certain plants catching an insect are due to plant responses to their environment.

Explanation of Solution

The hormone community called gibberellins induces elongation of the cells, promotes cell division and affects seed growth. Gibberellins are transmitted to vascular tissue. Dwarf plants also lack either genes for the synthesis of gibberellins, or genes for protein receptors of gibberellins. Once treated with gibberellins, plants that lack the gibberellins genes but have receptors for gibberellins grow taller. Applying gibberellins to a plant will contribute to height gain.

Conclusion

Thus, the seed soaked in gibberellins will germinate faster than seeds not soaked in gibberellins because gibberellins affect the growth of the seed.