Examples of vascular plants include trees, shrubs, flowering plants in general, ferns and the so-called clubmosses or ground pines. Non-vascular plants are represented by plants such as mosses and liverworts. There are fairly dramatic differences between the two groups, and middle school students can learn about their differences by studying a variety of characteristics.
The key comparison between vascular and non-vascular plants is based on the vascular tissue itself. Vascular plants, like ferns and flowering plants, possess conducting vascular tissue of two basic types. One type, botanists -- scientists who study plants -- call xylem, and it consists of cells that conduct water and nutrients from one cell to another throughout the plant.
The other type of conducting tissue is called phloem. Rather than just water, the phloem carries a fluid or sap rich in sugar that the plant has manufactured through photosynthesis. Non-vascular plants -- although they, too, need water and nourishment from photosynthesis -- do not have these specialised conducting tissues. They must rely upon a simpler, more passive means of absorption and nutrient transport.
Roots & Rhizomes
Vascular plants have roots, rhizomes or both. Roots are typically, but not always, subterranean plant parts. They function to both anchor the plant in place and to absorb nutrients and water from the soil. Some vascular plants, like clubmosses and horsetails that are related to ferns, have rhizomes. Rhizomes are underground stems. They grow horizontally through the soil and serve to anchor the plant, and they enable the plant to spread and sprout in new locations.
Non-vascular plants have neither roots nor rhizomes. They have rather unspecialised masses of cells that grow and serve to hold the plant in place. Many non-vascular plants, like mosses and liverworts for example, rely on the entire plant body for absorbing water.
Vascular plants have true stems while non-vascular plants do not. The stems can range in size from a few inches for a plant like a clubmoss to more than 370 feet for the giant redwood. The vascular plant stem features both types of vascular tissue -- the xylem and phloem. Even in the giant redwood trees, the vascular tissue transports water and nutrients throughout the entire plant. Non-vascular plants do not have true stems with vascular tissue, and therefore their upward growth is extremely limited.
The leaf is a familiar plant structure. What we might consider a more or less typical leaf, the maple leaf, is one example. In ferns, the entire above-ground portion of each individual fern is essentially a leaf. Even a clubmoss, like the so-called ground pine, has tiny leaves distributed over most of the plant's stem and branches. Although non-vascular plants like mosses may have simple leaves, they are not like the leaves of higher plants since they lack vascular tissue.
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