Make your own free website on

Major Kinds of Plants

Nonvascular plants Nonvascular plants are simplest of all terrestrial types of plants. They have no way of transporting water internally. They don’t make any seeds or flowers. Since they don’t have the woody tissue needed to dwell on land, they reach heights of about 1-2 centimeters only. Mosses are simple rootlike plants that grow in spirals around a stalk. Rootlike threads called rhizoids are what hold them in place. Mosses live in damp environments, yet doesn’t require soil to grow. Mosses make use of the alternation of generations found in the life cycles of some plants to proliferate rapidly and still keep genetic diversity. Liverworts are simple rootless plants like mosses, but they have a flattened “leaf-like” body. The name “liverwort” comes from the idea that they look like livers. They are pioneer plants (don’t need soil) and grow in moist areas like moss.
Seedless Plants Seedless plants, also known as cryptogamia, have vascular systems that allow them to transport nutrients and water, but do not reproduce by seeds. Ferns are virtually leaf and root-free. It’s stems are branched off form lower stems. Horsetails are basically stems. They have rhizomes, which distribute adventitious roots. Each node of their leaves have non-photosynthetic scales. Their cell walls are made of silica, which means they are textured.
Gymnosperms Gymnosperms, or “naked seed plants,” have ovules that are exposed during fertilization. Conifers are specific gymnosperms that have conical reproductive structures. Examples of conifers include pines, firs, redwoods, and other large trees. Almost all conifers stay green all year round, meaning they are “evergreens.” The needle shaped leaves of conifers is well adapted towards dry and arid climates. The stomata are found in pits and a think cuticle covers the leaf to minimize water loss. Conifers are the largest and oldest living organisms on Earth.
Angiosperms Angiosperms, or flowering plants, form seeds in protective chambers called ovaries. They are classified into monocots (one seed leaf) and dicots (two seed leafs). Animals such as birds or the wind usually carry out the transfer of pollen to female sex organs. Water transfer in angiosperms is carried out through wide tubes called vessel elements. Fiber reinforces the xylem of angiosperms and therefore specializes in support. Fruits come from ripened flower ovaries. They function in protecting dormant seeds and are changed to help animals in seed dispersal.

Adaptations to land

Flowers The flower is the reproductive structure of angiosperms. The three-part carpel is the female reproductive system. It is made up of ovary, style, and stigma. The male reproductive structure is called the stamen and it’s made up of the anther and its stalk, called a filament. Petals and sepals are used to attract pollinators.
Pollination The prerequisite to fertilization in angiosperms is pollination, or placing pollen on the stigma of a carpel, female reproductive system, by birds, wind etc.. Anthers release the pollen grains, animals or the wind carries them, and they end up on the sticky stigmas at the tips of carpels.
Vascular tissue The vascular tissue system in plants is formed by the xylem and phloem acting as a transport system for water and other essential nutrients. The two kinds of xylem cells are tracheids and vessel members. Xylem cells are dead at functional maturity. There are holes, or perforations between cells for water to pass through. Phloem functions mainly in the transport of sugars and is made up of adjacent cells called sieve tube members. Phloem cells are still alive at functional maturity.
Seeds A seed is made up of an embryo, seed coat, and some form of storage material (endosperm or cotyledons). The seed embryo is made up of an epicotyl, which turns in to the shoot tip. Young leaves called plumules are attached to the epicotyls. Under the epicotyl is the hypocotyl. A sheath called the coleoptile protects the epicotyl.
Fruits Fruits hold the seeds of vascular plants and are made from the reproductive organs called flowers. They aid in dispersal of the seeds and come in different forms. There are two types of fruits, simple or compound. Simple fruits develop from one pistil, whereas a compound fruit develops from many plant ovaries.