20 Traveling Seeds-Low

TRAVELING SEEDS FOCUS Question How does the structure of seeds help plants survive?

Seeds What do corn kernels, peas, and dandelion puffs all have in common? They are all seeds! A seed is the part of a plant that can grow into a new plant. Each seed has a strong outer shell called the seed coat Inside the seed is a tiny plant, or embryo (EM-bree-oh). The embryo grows into a new plant. The seed also contains food for the tiny plant. This food gives the growing plant energy until it can make its own food. Before they can grow, seeds need to find the perfect place. Seeds can grow only in places with water, air, light, and space. Animals move by using their legs, wings, or flippers. How do seeds find the perfect place to grow? The way a seed moves depends on its size, shape, and the habitat where it grows.

Gravity Many seeds move by falling to the ground. Gravity causes them to move. Think about an apple. The fruit gets heavy and falls off the tree. The fruit may roll a little, but it stays close to the tree. Inside the fruit are the seeds. The fruit may rot and release seeds. Softer fruits may break open when they fall. Eventually, the seeds get buried in the soil. There they can sprout into new plants.

Wind Some seeds move farther away from their parents. This way, new plants do not have to compete with their parents for water, sunlight, and space. The wind can blow seeds far away. Seeds that move by wind have special parts to help them lift up and blow away. For example, dandelion seeds are very small and light, with a puff of fluff on top. This makes it easy for them to fly in the wind. Think About It Why do you think a dandelion produces so many seeds?

If you have ever watched an old Western movie, you probably saw tumbleweeds rolling down a dusty street. Tumbleweeds are dried-up plants that still have seeds. As the tumbleweeds roll, seeds break off and land in new places. Tumbleweeds can spread their seeds very far. Maple seeds also move in the wind. These seeds are sometimes called whirlybirds or helicopter seeds. They have thin wings that help them spin and fly in the wind. Math Moment Winged seeds can travel 200 miles. in the wind, while dandelion seeds can travel 500 miles How much farther can the dandelion seeds travel?

Animals Have you ever seen a bird with a berry or a squirrel with a nut? If so, you know another way that seeds move. Animals carry them. Animals carry seeds to new places. Insects move seeds only short distances, but birds can carry seeds far away. Ants that move seeds use them for food. They eat the seed coat and leave the embryo to grow. Some animals, such as squirrels and birds, bury seeds in the ground to eat later. This keeps them from being eaten by other animals. Most of the seeds do get eaten, but some of the seeds grow into new plants. Wowser! Scientists found 32,000-year-old seeds in an old animal burrow. Amazingly, the scientists were still able to grow the seeds!