Plants are one of the most numerous andvarious forms of the kingdoms of living nature. They give all living beings the opportunity to breathe clean air, producing oxygen in the process of photosynthesis. They provide people and many animals with food and useful substances, beautify our life and make it beautiful. Angiosperms are one of the most diverse parts of this remarkable kingdom. About them also we will talk further.
Angiosperms: classification
This department includes in its composition two huge in number class:
- monocots;
- dicotyledonous.
Each of them is valuable not only fornature in general, but also for people in particular. After all, it is only necessary to name at least a few representatives who have monocotyledonous and dicotyledonous plants in their composition, examples will immediately confirm their immense practical role in human life. So, they are:
- Rye, wheat, oats, rice, buckwheat;
- rose hips, potatoes, tomatoes, eggplant and other crops;
- a huge number of medicinal herbs.
In general, the diversity of angiosperms is calculatedhundreds of thousands (about 350,000). In this case, monocotyledonous, and dicotyledonous plants, examples of which can be brought for very long, have their own peculiarities in the structure, lifestyle, life processes. We will consider one of the classes - dicotyledons. We will understand what characteristics these plants possess, what they are related to and what their significance is.
Dandelion class families
The classification can be different. There are several options:
- the Takhtadzhyan system;
- the Rivila system;
- APG;
- Dahlgren and Thorn;
- Cronquist.
Each took as a basis certain features anddivided the entire class into orders, families, or subclasses. For ordinary people, a taxonomic unit, such as a family, is more familiar with the school bench. Therefore, we list the most common and numerous groups that make up the class under consideration.
- Moth, or Legumes. What plants do dicotyons refer to here? For example: pea seed, alfalfa, clover, peanut, ration, acacia, astragalus, chickpea, ceratonia and others.
- Rosaceous. Examples: dog rose, apple, pear, plum, strawberry, raspberry and others.
- Cruciferae, or Cabbage.A typical representative is cabbage. Dicotyledonous plant, an example of which can still be attributed to this family - radish. And also: mustard, rape, sverbiga, shepherd's bag. There are about 3 thousand species.
- Complex color - include in its composition a large number of weeds, medicinal, fodder and food plants. Representatives: chamomile, dandelion, aster, cornflower, sunflower and others.
- Nightshade.Dicotyledon, an example of which can be cited here, is tomato. And with it, and most of the important vegetable crops cultivated by man (potatoes, eggplant and others). To the same family belongs a very poisonous belladonna.
Less well-known for our country are such families as:
- Laurels;
- Fatty;
- Portulaca;
- Grape;
- Myrtovye;
- Pumpkin;
- Begonium;
- Nutty;
- Willow;
- Umbrella;
- Birch and others.
In fact, there are a lot of them, so it's hard to list everything. Let us now consider what common features all representatives of bipartite possess.
Features of the structure of dicotyledons
Like all higher plants, they have a stem,leaves, root, flower. If it is a question of wood forms, that is a trunk and branches. In general, the structure of a bipartite plant does not differ from that of others. However, there are some peculiarities that make it possible to classify these or other species precisely to this class.
These characteristics are theira distinctive feature is precisely from monocotyledons, because all the flowers are the same in basic parts, it is difficult to correctly correlate species by taxa, if you do not know the special features.
Main features
So, these are the following parameters:
- Venation of leaves in most cases mesh.
- The root system is pivotal, often perennial.
- Formula of the structure of the flower: H4L4T2 + 4P1. In general, the number of parts must be a multiple of either 4 or 5.
- Between the xylem and phloem is a layer of cambium, so many forms have a lignified stalk.
- The leaf blade is often severely dissected.
These signs of dicotyledonous plants do not say that all representatives are arranged only in this way, and not otherwise. As elsewhere, there are also exceptions, some combinations.
However, the most important feature is that the seedsDicotyledons have two cotyledons located opposite each other. On the example of peanuts or beans, this can be clearly seen with the naked eye. This characteristic is typical for all without exception of representatives of dicotyledons. It was for him that they got their name.
Dicotyledonous plants: examples, photos
We have already cited many examples of differentrepresentatives of this class. However, mainly stopped only on those species that grow in our country. Below you can see a photo of some foreign endemics, to which climatic conditions of Russia do not fit. This, for example:
- laurel;
- delonix royal;
- sundew;
- sarrachenia;
- non-pentes;
- teak;
- black and mahogany and others.
The photo shows that they all have beautifully and brightly colored coronets. In general, almost all dicots have spectacular flowers. However, there are exceptions among weeds.
Interesting Magnolia.Each species is a dicot plant. An example of the representative of this family is the magnolia star. Very beautiful and fragrant plant of the East. It is composed of unusual and romantic legends. Magnolias are a part of the culture of many southern countries.
Spicy plants
The dicotyledonous plants include representatives of the most fragrant, fragrant species - spicy. For example, such as:
- cinnamon tree;
- laurel;
- coriander;
- caraway;
- anise;
- dill;
- parsley;
- sweet pepper and others.
Of course, their role in the food industry is great.After all, in addition to the direct purpose of improving the taste of the prepared dishes and giving them a special flavor, they are also used as medicinal forms.
Umbrella
Class Dicotyledonous plants include in its compositiona family such as Umbrella, or Celery. Their main distinguishing feature is a characteristic inflorescence in the form of an umbrella. Small collected in flower bundles of pale, rarely bright color. However, what really distinguishes them is the smell. All representatives contain a large number of essential oils, tannins, alkaloids. Therefore, the fragrance of umbrella is spread far away in the area in the area where they grow.
Representatives are as follows:
- coriander;
- carrot;
- azhgon;
- celery;
- fennel;
- parsnip;
- milestone poisonous;
- hemlock;
- cowworm;
- the volostushka;
- astratsiya;
- feverweed;
- and other.
There are both poisonous and very useful plants for humans. Also many are decorative.
Rosaceous
The most popular representative is a dog rose orrose flower. This bipartite plant, an example of which is always cited, hardly speaks of the Rosaceae family. But, of course, not only it is part of this delicious taxon. Why delicious? Because this includes:
- raspberries;
- cherry;
- plum;
- quince;
- figs;
- Apple tree;
- irga;
- Rowan;
- apricot;
- cherries;
- almonds and other very appetizing representatives.
Besides taste qualities, they are also valuable owners of vitamins, useful macro- and microelements and various compounds.
There are also common herbaceous forms amongst the representatives: the vulgaris, nettle, hemp, gravel, and others.
Complex colors
This family includes herbaceous, rarelywoody plants-perennials. Representatives are so numerous that they are found almost all over the globe. There are complex colors in the tropics and in the Arctic. This is the most numerous and diverse group of all dicots.
Examples can lead hundreds. Let's name the most famous ones to make it clear which specific plants are talking about:
- aster;
- sunflower;
- dandelion;
- dahlia;
- chicory;
- marigold;
- chamomile;
- daisy;
- serpuha;
- ragweed and others.
The most interesting representatives are:
- spleen cartilage;
- brahilena merana.
They are interesting because they are very powerfultrees up to 20/40 meters high, respectively. Scalea has very fragrant yellow flowers, collected on tops of branches. A lot of such trees form whole forests in the Galapagos Islands.
Brachilena of the merana grows in South Africa and in Madagascar. Height up to 40 meters. Flowers are very large, collected in panicles on the tops of branches.
