Jun 8, 2018 · Pinophyta (pī´nŏf´ətə), division of the plant kingdom consisting of those organisms commonly called gymnosperms. The gymnosperms, a group that includes the pine, have stems, roots and leaves, and vascular, or conducting, tissue (xylem and phloem).

May 21, 2018 · Conifer Conifer (common name for phylum Pinophyta) is a type of tree that thrives in temperate and boreal climates. Characterized by seed-bearing cones, conifers typically have narrow, needle-like leaves covered with a waxy cuticle, and …

Polypodiophyta (pŏl´ēpō´dēŏf´ətə), division of the plant kingdom consisting of the plants commonly called ferns. The ferns are vascular plants with stems, roots, and leaves. The small and inconspicuous gametophyte and the large spore-producing fern plant are quite independent of each other. Source for information on Polypodiophyta: The Columbia Encyclopedia, 6th …

May 14, 2018 · Gymnosperm Gymnosperms are one of the two major groups of plants that produce seeds; the other is the angio-sperms. Gymnosperm literally means “ naked seed, ” which refers to the development of seeds exposed on a flat structure, that is, not within an ovary as in the angiosperms. Gymnosperms became common about 290 million years ago and although many of the earlier types are now extinct ...

May 18, 2018 · Evolution of Plants Plants, descended from aquatic green algal ancestors, first appeared on land more than 450 million years ago during or prior to the Ordovician period. This event preceded the colonization of land by four-footed animals (tetrapods), which occurred considerably later in the Devonian period (408 to 360 million years ago). Understanding the origin of plants is important because ...

Economic Importance of Plants Plants are extremely important in the lives of people throughout the world. People depend upon plants to satisfy such basic human needs as food, clothing, shelter, and health care. These needs are growing rapidly because of a growing world population, increasing incomes, and urbanization . Source for information on Economic Importance of Plants: Plant Sciences ...