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division and expansion in seedlings, and promote the development of fruits. Some of the most important functions of gibberellins are to stimulate the germination of seeds and the renewed growth of apical buds in the Spring after a period of dormancy.

4. Cytokinin
Cytokinins were discovered in a search for things that will stimulate plant cells to divide. One source of cytokinins is coconut milk, the liquid endosperm. This suggests that in addition to being a food storage system, the endosperm may also influence embryonic development by promoting cell division. Cytokinins are produced in the roots, are transported through the xylem and stimulate the growth of the shoot, especially the lateral buds.

5. Auxins39.6 Auxins are produced by the apical buds. They inhibit the growth of lateral buds but promote the growth of lateral roots. This helps to coordinate the growth of the roots with the branches overhead. Together with cytokinins, auxins control the overall shape of a plant, the interactions between the two control the extent of apical dominance.Apical dominance means that the presence of an apical bud

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Together with gibberellins, the auxins promote fruit development. One of the major effects of auxins is to stimulate the elongationof plant cells.

C. Function and transport of auxin
1. Polar transport39.4
Plants don't have blood, so how do the hormones get around? Cytokinins move from the roots up to the shoots in the xylem sap. Auxin moves in the opposite way, from the tip down the shoot. It doesn't use the phloem