A special role in the evolution of the organic world is played by flowering plants. The organs of flowering plants have reached a sufficiently high level of development, providing this group of organisms with a dominant position on the planet. Today they are found on almost every continent. For comparison, you can cite statistics that contains a section of the school botany course "Organs of flowering plants" (Grade 6). Namely: among all higher plants, 850 species are gymnosperms, and 250 thousand are flowering plants.
Organs and functions of a flowering plant
Angiosperms are plants that form a flower and fruit.
All plant organs can be combined into two groups. Vegetative shoots consist of a stem and a leaf, as well as the underground part - the root. Generative are flower, fruit, and seeds. They are possessed only by flowering plants. The organs of flowering plants, depending on the structural features, perform certain functions. All of them play an important role in the functioning of organisms, determining their viability and adaptation to living conditions.
The organs and functions of a flowering plant are interconnected. Consider the structure of each of them in more detail.
Root
In the biology textbook in the subject "Organs of flowering plants" (Grade 6), the definition of the concept of "root" is given. This is an underground organ that provides fixation in the soil, nutrition with minerals, water supply, upward current and vegetative propagation.
Different types of roots have flowering plants. The organs of flowering plants are diverse. Distinguish the main root, subordinate and lateral. They combine special structures. Their name is root systems.
Types of Root Systems
Systematics isolate the root and fibrous root systems. The first is formed by a single main root and lateral ones extending from it. It is characteristic of representatives of the class Dicotyledons.
The fibrous grows in a bunch immediately from the shoot. It is characteristic of all representatives of the monocotyledonous family. This, for example, Cereal, Lily and Onion. Each of the systems has several advantages. For example, plants with a long main root can easily extract moisture from great depths. A fibrous system provides a large suction area.
Escape and its modifications
A large variety of aerial parts are characterized precisely by flowering plants. The organs of flowering plants sometimes change depending on environmental conditions. This is the adaptive ability of escape.
Its axial part is called the stem. The areas on which the leaves develop are nodes, and the distances between them are internodes. The angle between the plate and the stem forms the bosom of the leaf.
The lateral parts of the stem are also very diverse. Leaves with one leaf blade are called simple, with several - complex. In different ways, they can be located on the plant. For example, the leaves of birch and sunflower - alternately in a spiral, and in lilac and maple - opposite each other. A whorl is a leaf arrangement in which the plates develop in an amount of three or more in one node.
All vegetative organs perform the functions of asexual reproduction, mineral nutrition, photosynthesis and transpiration.
Organs of seed reproduction of flowering plants
A special organ of a flowering plant, where cells of sexual reproduction are formed, is a flower. Its main parts are the pestle and stamen. In them, the formation of germ cells occurs. The result of their fusion is a seed. It consists of a germ formed by the spine, stalk, leaflet and kidney, and the membrane.
The process of fertilization in flowering plants is preceded by pollination - transfer of pollen from the stamen to the pistil. This happens with insects, humans or wind. Further, with the fusion of the female reproductive cell and one sperm, an embryo is formed. The second is connected to the central germ cell, forming an endosperm. This is a reserve nutrient that the germ uses to carry out the processes of growth and development.
A seed surrounded by shells is called a fruit. They are also diverse. According to the structure of the pericarp, dry and juicy are isolated, and according to the number of seeds - single and multi-seeded. With the help of fruits, plants are spread and settled. Man, in turn, uses them as a food product. He also controls the number of plants used for their own purposes.
Fancy plants
The organs of flowering plants are often impressive in their shape and size.
The representative of gymnosperms velvichia is amazingly visually reminiscent of a ball of snakes. That is how its long, broad leaves look, reaching a length of up to two meters. The plant grows in desert open landscapes, where strong wind flows tear along the leaves of Velvichia. This creates the effect of a snake nest. And the shoot of an amazing plant is underground.
Under the supporting roots of the ficus banyan tree, the number of which is about 4 thousand, 5,000 people can easily fit.
The modified leaves of sundew and pemphigus are very sticky, have specialized digestive glands or closing traps. The thing is that they are predator plants capable of assimilating animal proteins. They can feed on small insects, crustaceans, and fish fry.
The vegetative and generative organs of flowering plants have a complex structure, which determines the fulfillment of functions and ensures their predominance on Earth.