All plants that exist on the planet are so numerous and diverse that scientists have repeatedly tried to systematize them. To this end, they divided the representatives of the flora into different species and groups. This kind of sorting is based on their main characteristics. In our article, a systematic classification of plants will be given. In addition, their main features and structural features will be indicated.
Classification of plants: examples and signs
First of all, it is worth saying that plants are organisms capable of autotrophic nutrition. They independently produce organic matter - carbohydrate glucose in the process of photosynthesis from carbon dioxide and water. This process occurs in chloroplasts - green plastids. But on one condition: if there is sunlight. The biological name for this action is photosynthesis. This is the main feature that characterizes the plant kingdom, the classification of which is based on the features of their structure within the framework of the evolutionary process. Herthe founder is Jean-Baptiste Lamarck, who introduced double (binary) species names. The classification of plants (table with examples) is given at the end of our article.
Inferior plants
The first and most primitive plants that arose in the process of evolution are algae. They are also called inferior. It is also a systematic classification of plants. Examples of this group: chlamydomonas, chlorella, spirogyra, kelp, sargassum, etc. Lower plants are united by the fact that their body is formed by individual cells that do not create tissues. It is called thallus or thallus. Algae also have no roots. The function of attachment to the substrate is performed by filamentous formations of the rhizoid. Visually, they resemble roots, but differ from them in the absence of tissues.
Higher plants
Now consider plant species, the classification of which is based on the complication of the structure. These are the so-called first land migrants. For life in this environment, developed mechanical and conductive tissues are necessary. The first land plants - rhinophytes - were small organisms. They were devoid of leaves and roots, but had some tissues: primarily mechanical and conductive, without which the life of plants on land is impossible. Their body consisted of aboveground and underground parts, however, instead of roots, there were rhizoids. Reproduction of rhinophytes occurred with the help of cells of asexual reproduction - spores. Paleontologists claim that the first higher land plants arose 400 million years ago.
Higher spore plants
The modern classification of plants, examples of which are given in the article, involves the complication of their structure due to adaptation to changing environmental conditions. Mosses, club mosses, horsetails and ferns are among the first terrestrial organisms. They reproduce with spores. In the life cycle of these plants, there is an alternation of generations: sexual and asexual, with the predominance of one of them.
Higher seed plants
This vast group of plants includes organisms that reproduce generatively with the help of a seed. It is more complex than disputes. The seed consists of an embryo surrounded by a reserve nutrient and a peel. It protects the future organism from adverse conditions during development. Thanks to this structure, the seed is more likely to develop and germinate, although certain conditions are needed for this: the presence of heat, a sufficient amount of solar energy and moisture. This group combines two divisions: holo - and angiosperms.
Gymnosperms
The characteristic features of this division is the absence of flowers and fruits. Seeds develop openly on the scales of cones, that is, naked. Therefore, the plants of this group received such a name. Most gymnosperms are represented by conifers. They are characterized by the apical growth of the shoot, the presence of special passages filled with resin and essential oils. The needle-like leaves of these plants are calledneedles. Their stomata are also filled with resin, which prevents excessive evaporation and unwanted moisture loss. Therefore, most conifers are evergreen. They do not shed their leaves with the onset of the cold season. Cones of all gymnosperms are not fruits, because they do not form flowers. This is a special modification of the shoot, which performs the function of generative reproduction.
Angiosperms
This is the largest group of plants that are the most complex. They currently dominate the planet. Their characteristic features are the presence of flowers and fruits. The angiosperms, in turn, are divided into two classes: mono- and dicotyledonous. Their main systematic feature is the corresponding number of cotyledons in the seed embryo. A brief classification of plants, examples and main features of the structure of the main systematic units are given in the table. It illustrates the complication in the structure of organisms in the process of evolution.
Plant classification: table with examples
All representatives of the flora can be systematized. Let's summarize all of the above with the table below:
|
Name systematic units |
Characteristic features |
Examples |
| Inferior plants | Lack of tissues and organs, aquatic habitat. Bodyrepresented by thallus and rhizoids | Ulva, ulotrix, fucus |
| Higher gymnosperms | The absence of flowers and fruits, the presence of resin passages in the wood, the leaves are needles | Spruce, pine, larch |
| Higher angiosperms | Presence of flower and fruit | Apple, eggplant, rose |
| Monocots | One cotyledon per seed embryo, fibrous root system, simple leaves, no cambium | Lily, garlic, rye |
| Dipartite | Two cotyledons in the seed germ, tap root system, simple and compound leaves, presence of cambium | Ash, grapes, sea buckthorn |
The existing classification of plant organisms greatly facilitates the process of their study, allows you to establish the characteristics and relationships between different groups.
