Twelfth Grade, Plant Biology Science Experiments (Page 5)

What Color Are the Leaves Really Turning?

Science Fair Project Idea

Scientific Method

Everyone loves the beautiful colors of fall, but where do they come from and how does the change in colors happen? In this project, you will uncover the hidden colors of fall by separating plant pigments with paper chromatography. What colors will you see? Read more

Are Soil Microorganisms Important for Plant Health?

Science Fair Project Idea

Scientific Method

Soil may look like a bunch of dirt, but good quality soil is actually a complex mixture of dirt, nutrients, microorganisms, insects and worms. What type of benefit do these microorganisms offer a growing plant? You can test this by baking soil in the oven to sterilize and kill the microorganisms. Do plants grown in sterile soil do better than plants in unsterilized soil? What about adding worms to one plant, but not to the other. Will the plant with worms grow better? Some insects are bad… Read more

Can Water Plants Be Used to Determine Water Quality?

Science Fair Project Idea

Scientific Method

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

Cryopreservation: Freezing Plant Tissues

Science Fair Project Idea

Scientific Method

Cryopreservation—storing seeds in ultra-cold liquid nitrogen—is one method for maintaining plant genetic stocks in seed banks. Can seeds withstand a really deep freeze and still germinate? Read more

Do Different Tree Species Grow at the Same Rate?

Science Fair Project Idea

Scientific Method

Trees grow more during the early spring than they do the rest of the year. Because of this period of dormancy, or lack of growth, each year of growth is marked by a line called a tree ring. You can count the number of rings in the cross section of a tree trunk to show how old the tree is. You can also count the number of rings in a stem to see the age of a stem or branch. One way to measure the rate of growth of a tree is to count the number of rings per inch. Trees with high numbers of… Read more

Earthworm Castings — The Ideal Proportion in Soil for Young Garden Plants

Science Fair Project Idea

Scientific Method

Everybody knows that worms are good for the soil, but not everybody knows why. Here's a project that investigates just one of the ways earthworms improve the earth. Would earthworm castings (or earthworm manure) help your plants prosper and flourish? If so, how much should you use? Read more

Experiment with Factors that Affect Roundup® Weed Killer

Science Fair Project Idea

Scientific Method

Farmers are constantly battling various types of weeds that compete with the crops they are trying to grow. One of the tools they use to combat unwanted plants is a chemical called glyphosate. Glyphosate is the active ingredient in Roundup, a widely used weed killer. In this plant biology science fair project, you will explore the factors that affect the activity of glyphosate. Read more

Fruit Ripening

Science Fair Project Idea

Scientific Method

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

Fungi Spores

Science Fair Project Idea

Scientific Method

Mushrooms are not plants, but are fungi. Fungi include mushrooms, molds, and lichen. They do not produce seeds to reproduce like some plants. Fungi produce spores, like more primitive plants do. The spores of a mushroom are contained in the tiny folds around the stem underneath the mushroom cap. Different species of mushrooms have different types of spores, with different colors and different patterns of folds. You can make mushroom prints by removing the stem from a mushroom and placing the… Read more

Harmful or Helpful? The Effects of Hydrogen Peroxide on the Roots of Plant Cuttings & on Seed Germination

Science Fair Project Idea

Scientific Method

Hydrogen peroxide (often used as a disinfectant) has also been approved for use in pesticides. This science fair project investigates whether hydrogen peroxide has any effects on seed germination or on roots of plant cuttings. Read more

Twelfth Grade, Plant Biology Science Experiments (63 results)

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