科一科二 · 科一
From Secd to PUMPKIN
When sping winds warm the eath, a famer plantshundreds of pumpkin seeds.
Every pumpkin seed can become a baby pumpkin plant. Underground, covered with dark, moist soil, the baby plantsbegin to grow. As the plants get bigger, the seeds crack open. Stems sproutup. Roots dig down. Inside the roots are tubes. Water travelsup these tubes the way juice goes up a straw.
In less than two weeks from planting time, green shootspoke up through the earth. These shoots grow into tinyseedlings. Two leaves, called seedleaves, uncurl on each stem. Theyreach up toward the sun.
Sunlight gives these leaves energy to make food. Like us, plants need food to grow. But green plants do not eat foodas we do. Their leaves make it. To make food, plants need light, water, and air. Leavescatch the sunlight. Roots soak up rainwater. And little openings in the leaveslet air in. Using energy from the sun, the leaves mix the airwith water from the soil to make sugar. This feeds the plant.
Soon broad, prickly leaves with jagged edges unfold on the stems. The seed leaves dry up. Now the new leaves make food for the pumpkin plant.
