Saltar la navegación

7.3.5. Metaphytes

Kingdom Plantae or Metaphyta or Vegetal

The plant or plant kingdom (Plantae) or Metaphytes, groups eukaryoticmulticellular living beings, whose cells are surrounded by a cell wall of cellulose, without locomotor capacity, and autotrophsThat is, they make their own organic matter from inorganic substances such as carbon dioxide, water, and mineral salts.

The plant kingdom is made up of about 26,000 different species. Most of them live in the terrestrial environment, although the most primitive plants, such as mosses and ferns, still need water to reproduce. The cells of the most evolved plants form true tissues and organs, which has allowed them to colonize all environments.

Plants reproduce by sexual reproduction. In their reproductive cycle, plants alternate a phase of life in which they multiply by means of sporessporophyte, with another, that of gametophyte, in which they produce gametes that will unite to give rise to a new sporophyte. In addition, in many cases they can also have asexual reproduction, forming complete individuals from a fragment of the adult plant, giving rise to an individual identical to the parent.

Classification of plants

To classify the plants we must take into account some criteria:

  • Depending on the existence of the circulatory vessels, we can have:
    • Vascular plants: with conductive tissues.
    • Non-vascular plants: without conductive tissues.
  • According to the presence/absence of rootsstems and leaves.
    • Bryophytes: no roots, no stems, no leaves.
    • Cormophytes: with roots, stems and leaves
  • According to the presence/absence of flowers.
    • Cryptogams: without flowers, such as mosses and ferns.
    • Phanerogams: with flowers, like the rest of the phanerogams.
  • According to the presence/absence of fruits.
    • Gymnosperms: no fruit or ovary, so the ovules are naked on their bracts.
    • Angiosperms: with fruits, ovary and seeds enclosed in it.
  • According to the number of cotyledons, leaves that come out of the seed when germinating. So in angiosperms we can see seeds germinate: