The fetus of angiosperms is formed from the ovary of the pistil

Juicy tomato, fragrant pear, dry acorn and exotic carambola - all this can be called one phrase - "the fruit of angiosperms". It is formed from a flower and is widely used by man in his life. How this plant organ is formed will be discussed in detail in our article.

Which plants are related to angiosperms

Angiosperms now occupy a dominant position on the planet. The department of this plant kingdom numbers more than 250 thousand species. They reached this level of distribution due to the progressive features of their structure. They are characterized by the presence of a generative organ of reproduction - a flower, double fertilization. Such plants multiply not only vegetatively, but also with the help of seeds. The fetus of angiosperms is formed from a flower.

Features of double fertilization in flowering plants

The main functional parts of the flower are the stamen, in which the male sex cells develop, and the pestle. In this part there are female gametes and the central germ cell. The process of fertilization in flowering plants is preceded by pollination. It consists in transferring the pollen from the anther of the stamen to the stigma of the pistil. This process occurs with the help of wind, water, insects or a person.

The fetus of angiosperms is formed from the lower extended part of the pistil, which is called the ovary. In the process of fertilization involved two sperm. Once at the stigma of the pistil, they can not move independently into the ovary of the pistil. This happens with the help of a germ tube. It gradually sprouts downward - from the stigma through the column to the ovary. And along with it, a pair of male gametes also descends. This structure of the flower can be compared with the elevator of a multi-storey building.

Having reached the ovary, one sperm connects to the egg, forming a seed germ. It contains all parts of the future plant. It is an embryonic root, a stem, a leaf and a kidney. And the second sperm merges with the central germ cell. As a result of their connection, endosperm is formed, which serves as a reserve nutrient. With the passage of time, a seed is formed inside the fruit. It consists of an embryo, a layer of endosperm and skin. The seed is a generative organ of flowering plants.

Fruit of Angiospermous Plants

One of the progressive features of flowering plants is that their seeds are under reliable protection. Since the fetus of angiosperms is formed from the pestle, its walls protect the developing seed from all unfavorable environmental conditions. This generative organ of plants consists of seeds and pericarp, which, in turn, is formed by three layers: external, middle and inner. Depending on the structure, dry and juicy fruits are distinguished. For example, the drupe of cherries and plums has an outer filmy, fleshy middle and ossified inner layer.

From what the fetus is formed in angiosperms

In the predominant majority of cases, the fetus of angiosperms develops from the walls of the pestle ovary. In this case, it is called the present. Examples of such structures are a drupe, a berry, a bean, a box, a seed. If additional parts of the flower take part in the formation of the fruit, it is false. It can be an overgrown flower, a calyx. False is the juicy multi-seed apple fruit, which is characteristic not only for the same-named representative of the family Rosaceae, but also for quince, mountain ash, dog rose, hawthorn, irgi. All the familiar black and red currants, elder, gooseberries, viburnum, dogwood have a similar structure.

Structure and classification of fruits

Since the fetus of angiosperms develops from parts of the flower, their structure is interrelated. This is easy to prove. For example, if the pestle in the flower is one, it produces as many simple fruits. In the case when numerous ovaries coalesce with each other, a complex generative organ is formed. This is what happens with raspberries. This fruit is the result of a growing number of drupes. And strawberries and strawberries have small nuts immersed in a juicy and fleshy base of the flower-box.

Fruits are grouped together in several ways. First of all, this is the number of seeds. The second - the features of the structure of the pericarp. The first sign distinguishes one- (drupe, seed) and multi-seed fruit (berry, capsule). On the second sign - juicy (Pomeranian, pumpkin) and dry (bean, walnut).

The importance of fruits in nature

Fruits are of great importance for spreading seeds and planting. Having a juicy and tasty protective shell, they are a favorite treat for many animals. Eating fruits, herbivores simultaneously spread the seeds, moving from place to place. The layers of the pericarp are a reliable protection of seeds from changes in environmental conditions, temperature fluctuations, lack of moisture and heat. A man has long been using fruits in food, artificially cultivating many kinds of fruit, berry, melons and fodder crops. Every year, plant breeders create new plant species with high yields.

Thus, the fetus of angiosperms is formed from the walls of the pestle, as well as other parts of the flower: the flower-root or carpels. In any case, the fruit is the result of flower development, double fertilization and performs the function of plant reproduction.