Kingdom of Plants began to evolve more than 500 million years ago. At that time the planet was very different from the one we know today; in fact, it was so different that we would not have been able to survive, as it was common for asteroids and comets to hit Earth on a daily basis.
So much so that the first plant life originated in the seas. First they were cells that gave shape to increasingly complex organisms: like mosses. Later the first plants would appear that would come out of the surface, and later the terrestrial ones would do it.
What is the Plantae kingdom?
In its broadest sense, the Plantae kingdom is that of all living beings whose functions include photosynthesis; that is, transform the energy of the sun and oxygen into sugars, which are their food. But apart from the plants themselves, algae are also included in this kingdom. In fact, no plant would exist today if it weren’t for algae. They are your direct ancestor; the first to colonize the planet.
Now, it is also important to say that, unlike animals, there is no living being of the kingdom Plantae that is capable of walking. Wherever it sprouts, it is normal for it to stay there forever. Another very different thing is the ability to climb, something that species such as the Parthenocissus tricuspidata (virgin vine), or the clematis vitalba (clematis).
Classification of the kingdom Plantae
There are an estimated 323.674 species of organisms that belong to this great kingdom, distributed as follows:
Plants without flower
- rhodophyta: they are red algae, aquatic organisms that appeared in the Mesoproterozoic (about 1600 million years ago). They are capable of photosynthesis, since they have chlorophyll. There are about 7000 varieties.
Examples: Laurencia, chondrus crispus.
- Chlorophyta: green algae inhabit both fresh and salt water. There are some that even form lichens. There are an estimated 4242.
Examples: Pediastrum, Ulva.
- Bryophyta: They are mosses, very primitive terrestrial plants that inhabit shady and humid areas. They have leaves and stem, but no roots, if not rhizoids thanks to which they absorb water and nutrients from the soil. There are about 24 thousand.
- pteridophyta: ferns and the like. They are plants that live near humid areas, often sheltered from the sun, and that produce spores on the leaves. There are about 12 thousand varieties. Examples: Blechnum humps, Asplenium’s nest.
- gymnosperms: Gymnosperms (conifers, Ginkgo), are those that do not have flowers or fruits themselves, and that also depend on the wind for pollination. There are about 1052. Learn More.
- Angiosperms: are the flowering plants and those with true fruits. Despite being the most modern, they are also the most numerous with 280.000 species. Learn More.
How are plants classified in the kingdom Plantae?
If we focus only on plants, leaving out algae and mosses, they are divided into gymnosperms, which are those that do not have showy flowers; and angiosperms that do.
It is a series of vascular plants that produce seeds, but these are “naked”; that is, they are not formed from a closed ovary and therefore have nothing to protect them. The flower is actually a branch that produces fertile leaves, also called sporophylls. As the seed is exposed, these plants do not have proper fruits.
They appeared during the Mesozoic Era, more than 250 million years ago, and they haven’t changed much since then. This includes cycads, conifers, gnetids (such as Welwitschia mirabilis) and a tree, the Ginkgo biloba.
It is estimated that there are 15 botanical families, with about 80 botanical genera and about 820 species, some of which are the following:
- araucaria auracana: it is an endemic conifer of the Argentine Patagonia. It reaches 50 meters in height, and has a straight, cylindrical trunk. The branches sprout from several meters above the ground, and acicular leaves that end in a point emerge from them. See file.
- Cycas rolled: it is a plant that grows in Asia, specifically in the East. It has a false trunk from which a crown of pinnate and leathery leaves sprouts every year. From the center, the inflorescence arises, which can be female or male. The first is round and compact, and the other is long and narrow. See file.
- Pine tree: it is the stone pine, native to the Mediterranean region. It develops a tall trunk of 50 meters or more, with an irregular crown formed by acicular leaves. See file.
Angiosperms are the plants that do have flowers and that also protect their seeds. They appeared during the Cretaceous, about 145 million years ago, and continue to evolve today. They establish relationships with other animals, making them their pollinators, and therefore the ones that are most successful when it comes to producing fruit with seeds.
They are the most successful. Not only have they managed to conquer much of the world, but they are also the ones we use the most when we design gardens. The enormous variety of angiosperms that exist – it is estimated that there are some 257 thousand different species – makes this possible. In addition, two types of angiosperms can be differentiated:
- Monocotyledonous: are those whose seed only has a single cotyledon. This means that when germinating only a single primitive leaf will sprout, which will have parallel veins. Its roots are adventitious, and it produces flowers with three or a multiple of three petals. Examples: herbs, including palm trees.
- Dicot: they are plants that have two cotyledons in the seeds, which when germinating have two leaves. Also, the veins of the leaves have a reticular distribution.
- Phoenix dactylifera: is the date palm. Native to southwest Asia, it develops one, or usually several trunks up to 30 meters high, crowned by bluish-green pinnate leaves. See file.
- tulip: The tulip is a bulbous plant that blooms in spring and remains dormant the rest of the year. It is originally from India, although the Netherlands is one of the main producers. See file.
- wisteria sinensis: Wisteria is a deciduous climbing shrub endemic to China. It can reach 30 meters in height, and has bright green pinnate leaves. Its clusters of flowers appear in spring, and are lilac. See file.
What is the importance of the kingdom Plantae?
Plants, algae and mosses are very important for other living beings, for these reasons:
- They are the main source of oxygen: phytoplankton, which is made up of algae, produces 50% of all the oxygen on the planet.
- They absorb carbon dioxide: by photosynthesis, they absorb CO2, thereby helping to improve air quality.
- They play an important role in various ecological cycles: like nitrogen for example. There are many plants, such as legumes, that fix nitrogen to the soil. Thanks to this other species can grow.
- They have many uses for animals including humans: trees for example are a very good refuge during the summer, since their leaves protect from the sun; many are suitable for consumption, such as lettuce, rice or orange trees. Some of the wood is used, or to get some health benefit.
What did you think of this topic? If you need more information, click here to find out the types of plant species there are: