Lesson Plan - Get It!
Why do you think moss grows so close to the ground? Never thought about that? There's a lot about plants to think about!
Plants are all around us!
Welcome to our Plants series of lessons, where you will learn all about these amazing creations that you may take for granted!
They include tall trees growing in forests and the grass we find along sidewalks. Plants can live in lakes, ponds, and even the ocean! They come in all shapes and sizes, yet share a couple of common characteristics. All plants are considered photosynthetic autotrophs, meaning they obtain their cellular energy by converting sunlight into chemical energy.
Notice how the plant takes in sunlight, water, and carbon dioxide. Plants release glucose for energy and oxygen so that other organisms can breathe. Photosynthesis is a really important part of a plant's job!
All plants are considered to be multicellular eukaryotes. Remember that eukaryotes have a nucleus and membrane-bound organelles. (For more information on types of cells, see the Elephango lesson under Additional Resources in the right-hand sidebar.)
Plants are made up of many cells that contain nuclei and organelles. Organelles are the cellular structures that help cells function in the environment. Chloroplasts are the cell organelles responsible for carrying out photosynthesis. They contain green pigment, which is why plants are often green in color. Observe the image below — can you pick out the chloroplasts? They are the green structures near the top of the plant. They provide the energy for all the other organelles in the cell. Plant cells also have a cell wall, which is different from animal cells. Notice how the cell wall protects the cell and helps give it structure:
Did you know that not all plants are green? Some plants have a blue or red pigment in the cells that causes leaves to be different colors. Flowers are another plant structure that bloom for reproduction but do not carry out photosynthesis. Other plant structures, like the stem and branches, can carry out photosynthesis!
There are two types of plants: vascular and nonvascular.
- Vascular plants have specialized structures that help move water and food throughout the plant. These are called "xylem" and "phloem." The xylem moves water, while the phloem moves food and nutrients. These tissues are bundled together in most plants. If you cut a piece of celery, you can see the vascular bundles inside! Try placing the celery stalk in water with a little bit of food coloring. Check back on your experiment after a couple of hours; can you see color moving up the stalk? That is the vascular tissue moving the material into the plant for use!
- Nonvascular plants do not have special structures that help move nutrients and water, which is why they do not grow up from the ground like other plants. Mosses and liverworts are good examples of nonvascular plants.
In which group do you think you would find flowering plants? If guessed vascular, you guessed correctly! Vascular plants can be divided into three groups based on how the plant reproduces.
Nonvascular plants reproduce using spores, tiny reproductive structures that can grow into a new plant. Each of the browndots in the photo below is a spore. Spores are carried by wind, water, and animals to new locations, where they will produce new plants.
Vascular plants with flowers are called "angiosperms," and use special structures in the flower to reproduce. You will learn more about this in another lesson in this Plants series, found under Related Lessons in the right-hand sidebar.
Finally, some plants use seeds in cones to reproduce. These vascular plants are called "
gymnosperms." Cones hold seeds, but do not protect them like flowers in angiosperms. These plants can live in many climates all over the world because they are well-adapted.
There are so many types of plants on our planet. All plants produce their own food using sunlight and are producers for ecosystems. They are multicellular, and contain organelles called chloroplasts. Plants can be classified as vascular or nonvascular based on the presences of special tissues for moving water and nutrients. Vascular plants can be broken down based on how they reproduce.
- What kinds of plants do you have in your backyard?
- Why might scientists care about how plants are classified?
Discuss what you have learned with a parent or teacher before moving to the Got It? section of this lesson.