In a previous lesson, you learned that plants are multicellular, which means they are made up of more than one cell. This feature allows plants to have specialized cells that perform certain functions.
You also learned that plants have organs, which are groups of specialized structures that perform certain functions. Roots, stems, leaves, and flowers are plant organs. Roots absorb water and nutrients from the soil. Stems transport water and nutrients and hold up the leaves so that they can receive the maximum amount of sunlight to photosynthesize. Flowers are reproductive structures, although not all plants have flowers.
View this slideshow to review some of the general characteristics of plants.
Vascular and NonvascularPlants are divided into two main categories: vascular plants and nonvascular plants. Vascular tissue is made up of specialized cells that transport nutrients such as water, minerals, and glucose. Nonvascular plants do not have vascular tissue. Nonvascular plants must grow in moist or wet areas. They cannot grow more than four inches high since they do not have the internal structural support to grow taller.
Seed Plants and Seedless PlantsThe main difference among vascular plants is their reproductive structure. The categories of vascular plants are named for this main difference. The vascular plants include the seedless plants and the seed plants. Seedless plants use spores instead of seeds as their means of reproduction.
Gymnosperms and AngiospermsThe seed plants are the gymnosperms and angiosperms. Gymnosperms are vascular plants whose reproductive structures are cones. Angiosperms are vascular plants whose reproductive structures are flowers.
Monocots and DicotsThe angiosperms (or flowering plants) are divided into two big groups called monocots and dicots. A main difference between monocots and dicots is that monocots have vascular tissue in bundles scattered through their stems, while dicots have vascular tissue arranged in rings, like the rings in a tree trunk.
Look at the two images. The image on the left is labeled monocot and shows vascular tissue that is distributed evenly throughout the stem. The image on the right is labeled dicot and shows vascular tissue that is arranged in rings. Notice the xylem and phloem in both images. Vascular plants absorb water from the soil with their roots. The water is then carried up to the leaves through vascular tissue composed of xylem and phloem. |
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Question 1
What is the function of vascular tissue in plants?
Question 2
How does the vascular tissue of a monocot differ from that of a dicot?
