To allow kids to experience the life cycle of plants up close, use this section with the 'Watch Seeds Sprout' science project.
Most plants start their life as some sort of seed. A seed has all of the information it needs to grow into a plant, but before it can grow, it needs certain conditions to be right. Until it is in the right conditions, the seed is dormant - it's kind of like it is asleep. When the seed has everything that it needs to live (sunlight, air, water, and nutrients from soil), it will 'wake up' and sprout, or germinate. The sprouted seed will soon grow a stem above the ground. Below the ground, it will grow roots. Soon small green leaves will grow out from the stem. At the top of the stem, a flower bud might begin to form (if it is a flowering plant). Eventually the flower bud will open up, or bloom, into a flower. New seeds will grow inside of the flower. The plant uses these seeds to produce new plants. If the plant is a type that produces fruit, such as an apple tree, the flower will slowly turn into a fruit that is still connected to the stem (or a branch) of the plant. The fruit gets nutrients and everything it needs from the roots, stem, and leaves of the plant it is growing on. Now the plant's new seeds are inside of that fruit. Eventually those new seeds will fall to the ground or be planted by a human and grow into new plants! The original plant may die right away after it completes its life cycle, or it may live for several more years.
Flower petals are a very important part of flowers. Besides smelling good, they also have a special job to do. They protect the parts of the flower that make seeds from weather and any harm that could be caused by animals or insects trying to eat them. The petals slowly open up as the flower blooms. Once they have opened, the petals have another job to do - they attract insects to come and drink the nectar inside the flowers.
In order for the seeds of flowers to be able to make more plants, they have to be pollinated. Most kinds of flowers rely on insects or other things in nature to do the pollinating for them. A bee is a common insect that pollinates flowers when it flies from flower to flower drinking nectar from deep inside the flower. As it rubs against the parts of the flower that contain pollen, some of the pollen usually sticks to the bee's body. Then the bee flies off to another flower to get more nectar. Most flowers have a long tube in their middle, with a sticky spot on the top called a stigma. When the bee gets to a new flower, some of the pollen will probably fall onto the flower's stigma and stick to it. Then the pollen slides down the tube to a place where it will help form a seed, or maybe many seeds!
Some other insects that help pollinate plants are ants, beetles, and butterflies. They are all attracted to the flowers for their nectar, but they end up carrying pollen from flower to flower in the same way that bees do.
In the first experiment, you learned that plants need certain conditions in order to grow. Do you remember what they are? Sunlight, water, and good soil with nutrients. Plants also need air. How does a plant use these things to grow? All green plants use a special process called photosynthesis to make food that they use to grow. Photosynthesis happens in the plant's leaves. How does it happen? Well, the plant's leaves soak up energy from sunlight. The leaves also gather a gas called carbon dioxide from the air. Inside the leaves, a very complex chemical reaction, called photosynthesis, happens between the energy from the sunlight, water from the soil, and the carbon dioxide from the air! Sugars that the plant can eat are created in the reaction. Oxygen is also released by the plant during photosynthesis, which is great for humans and other animals, since oxygen is the main gas that we breathe! Extra food that the plant doesn't use right away is stored in the leaves for later.
Read our newsletter about Chemistry to learn more about carbon dioxide, oxygen, and chemical reactions.
Germinate- when a seed begins to grow. Until it germinates, it is dormant, or asleep.
Dormant - something that is alive, but is temporarily not growing or having any physical activity.
Pollination - when pollen is transferred from one flower to another to form a seed.
Photosynthesis - a process that happens in the leaves of plants where sunlight, water, and carbon dioxide are converted into food and oxygen.
For gardening tips and other project ideas to try with your kids this season, check out these sites: