Plants are organisms that grow and reproduce their own kind. The need for, air, soil, water, light, and space to grow.
Plants need soil. Water and minerals are taken from the soil through roots. Soil also provides support for the plant and an anchor for the roots to grow in. Decaying plants and animals leave behind minerals in the soil that are essential for future plant growth.
Plants need sunlight in order to grow properly. They use light energy to change the materials - carbon dioxide and water into food substances (sugars). This process of food productions is called photosynthesis. Only in light can a green plant make food.
Plants most also have clean air. Green plants take in carbon dioxide from air and use it during photosynthesis to make food. Dirty, smoggy air blocks sunlight that plants must have.
Plants need water. Water is essential to all life on earth. No known organism can exist without water. Plants use water to carry moisture and nutrients from the roots to he leaves and food from the leaves back down to the roots.
Plants must also have space in order to grow. Plants are found everywhere - deserts, mountains, arctic regions, forests, jungles, oceans, and even in cracks of sidewalks of busy cities. If the space is small, the plants will be small and stunted. Big plants need big spaces for their roots and branches.
What do Plants Need to Grow?
- Topic Area
Biological Science: Plants--What do plants need to grow?
- Introductory Statement
Students will understand that in order to grow healthy plants, soil, water, light and air must be provided.
- Math Skills
- Recording data
Milk cartons--from school lunches
Bean, radish or corn seeds
Potting soil mixture
- Key Question
What do plants need to grow?
- Background Information
Plants require sunlight, water, soil and air in order to grow and be healthy, Energy received from the sun is used to convert carbon dioxide and water into food. When plants do not receive the things they need to live and grow, they will either die or be stunted in their growth.
- Management Suggestions
- Save the 1/2 pint milk cartons from the students' lunches, rinse them out and cut the tops off.
- Use fast growing seeds such as radish, corn, or bean seeds.
- Gather enough 1/2 pint milk cartons from the cafeteria for the class.
- Cut the top off the milk carton.
- Fill the carton with a soil mixture.
- Choose seeds that sprout fast, such as radish, bean, or corn.
- Plant the seeds in the milk cartons. Dampen the soil.
- After the seedlings sprout, divide them into four different groups.
- Subject them to different growing conditions.
- Condition #1-- Plant has soil, water, and air but does not have light. Put these plants under a box or in the closet.
- Condition #2-- Plant has soil, light, and water but no air. Seal these plants in a large clear plastic bag.
- Condition #3-- Plant has soil, light, and air but no water. Do not water these plants.
- Condition #4 --This is the control group. The plants have soil, air, light and water.
- When the seedlings come through the soil, measure each week how much the plants have grown in each environmental condition.
- Record each on a separate graph.
- After several weeks compare the graphs. Are there differences in rate of growth of the different plants in the separate condition?
- Discuss with the students what each plant needs in order to grow. (soil, air, light, and water)
- Have the students explain what the plants look like in each of the conditions and what need was lacking in each one.
- Have the students decorate the sides of the milk cartons with paper, roving, yarn, etc. and use them as pots for their plants.
What do Plants Need to Grow?
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