Video narration
What can the seed in a watermelon slice become? If that seed is viable, it can sprout: a root grows down, while a shoot pushes up and opens its first leaves. That tiny plant grows into a leafy vine, spreading across the ground, making flowers, and sending out new leaves as it lengthens. But here's the surprising part: not every flower becomes a watermelon. A female flower needs pollen from a male flower to reach it; successful fertilization lets the base of that flower begin growing into fruit. That transfer of pollen is called pollination. Behind the fading flower, a tiny watermelon starts to swell. As the vine continues to grow, the fruit grows larger and ripens on the plant. So what can that seed become? A vine with ripe watermelon fruit-but only after a female flower is pollinated and its tiny fruit grows.