The embryo in a seed contains everything that the seed needs to grow. The seed will not start to germinate until conditions are right. This usually means that the seed must be warm and moist. The embryo starts to grow, using its stored food supply, and soon bursts the seed coat. Usually the root emerges first, growing downwards in search of water, and the shoot follows. The first leaves to emerge are often fleshy organs that are part of the food store, and the leaves that appear later do not resemble them.
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