Fourth Grade, Plant Biology Science Projects (16 results)

Plants provide us with so much — oxygen to breath, food to eat, materials to make clothing and paper, and beautiful flowers and leaves to admire! How can plants be so diverse and survive in so many kinds of climates? How do they know how to grow towards the sun? Why do some plants not have seeds? Explore the amazing and beautiful world of plants.

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Science Fair Project Idea
To be able to live on Mars, humans need breathable air, clean water, and nutritious food. Spacesuits can provide oxygen to breathe, ice on Mars can be a source of water, but how could we get nutritious food? Today's astronauts bring food with them. But a manned trip to Mars would require food that was either successfully grown in space or on Mars, as taking the extra weight of food for such a long time—it takes 6–9 months one way—is just too costly. In this project, you will… Read more
Science Fair Project Idea
What do plants need to grow? Most of us would answer that they need light, air, water, and soil. But by using a process called hydroponics, you can grow plants without soil! How does it work? Try this project and see for yourself! Read more
Science Fair Project Idea
You might not know it, but plants are able to sense their environment and actually respond appropriately. One of the key parameters that every plant must respond to is the direction of gravity: stems go up (opposite to the pull of gravity) and roots go down (in the same direction as the force of gravity). In this project, you will construct simple devices that hold several germinating seeds, which allow you to watch how growing rootlets respond as you rotate the devices, effectively altering… Read more
Science Fair Project Idea
Plants need nitrogen to grow healthy stems and leaves. Although nitrogen is the most abundant element in the air we breathe, that form of nitrogen cannot be used by plants. Nitrogen contained in fertilizer, on the other hand, is readily taken up by plants. In this experiment, you will compare plants grown without nitrogen fertilizer to plants grown with nitrogen fertilizer. Read more
Science Fair Project Idea
Up, up, and away! If you have ever made a wish and blown the fluff of a dandelion, you have witnessed how some plants are adapted to spreading their seeds using the wind. The tiny, furry parachute allows the seeds to be picked up by the wind and to be carried far away from their parent plant. In this experiment, you will make models of seeds and fruit to investigate dispersal by wind and to evaluate the relationship between the structure of the seed and its ability to be dispersed by the… Read more
Science Fair Project Idea
We all know that plants need sunlight and water to grow big and tall. But did you know that inside seeds are baby plants, and that the fragile baby plant inside the seed needs to be protected? If you've ever had a sunburn, you also know that the sun gives off harmful radiation and heat. How much radiation and heat can a seed handle? Find out using some radish seeds, an oven, and your microwave! Read more
Science Fair Project Idea
Fruit is a strategy some plants use to attract animals to disperse seeds. The animals eat the fruit and disperse the seeds through the digestive system. To attract animals, fruit needs to ripen and develop an odor that acts as an attractant. How much more successful are ripe fruits at attracting animals? Try setting out an over and under ripe piece of fruit, and compare how many many insects are attracted to each fruit. How does ripening occur? You can do an experiment using a very ripe… Read more
Science Fair Project Idea
Like humans, plants can be negatively affected by overcrowding. Unlike humans, plants cannot get up and move to a new environment or explore how to utilize new resources. This experiment will explore the effects of crowding (population density) on the growth and health of plants. Read more
Science Fair Project Idea
Some plants grow only in water-logged environments. These plants are usually native to wetlands and are important for the sustainability of aquatic ecosystems. Wetland ecosystems are very fragile and susceptible to the toxic dumping of sewage and fertilizer run-off from neighboring farm land. One very common aquatic plant called duckweed inhabits many wetland marshes. Duckweed grows by asexual reproduction and floats at the surface of the water with tiny roots extending into the water below.… Read more
Science Fair Project Idea
Have you ever gone camping, looked up at the stars, and found the Big Dipper? Two stars in the dipper part of this constellation point to Polaris, the north star, which people have used for thousands of years to help them find their way. In this plant biology science fair project, you'll investigate whether plants, like moss, can help you find your way, too. Read more
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