The necessity of this stored food can be shown by taking a number of well-started seedlings, removing part of the stored food (in cotyledon or endosperm) in some of them, removing it all in others, and leaving still others unharmed. If these seedlings are then placed so that the root can dip into water, by suspending them on a netting over a well-filled glass, their development can be watched.
Several seedlings must be used in each group, lest we draw conclusions from too few instances, or perhaps be misled in case some one seed were abnormal. The conditions of growth must be the same in each case, lest it appear that these varying conditions, and not the loss of stored food, produces the results.
After a few days it will be seen that the whole seeds grow well and rapidly; that those with part of their food removed start more slowly and soon cease growing; while those with all the stored food removed scarcely start at all. This is because of the fact that, until the seedling can develop roots and leaves, it depends solely on this store of food whose removal is shown to have so serious results.
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