Fruits are a protective coating for plant seeds. They may be different in color, shape, size and taste, but they all have a similar structure. Fruits are vegetables, and fruits, and berries, and birch catkins, and nuts. It would seem that they are completely different, but they all have a lot in common.
Structure
Fruits are a set of substances that are designed to protect seeds from the environment and increase the chances of their germination. They are also designed to spread seeds as far as possible. This can happen with the help of wind, water, animals. Fruits consist of three parts: endocarp, mesocarp and exocarp. The first is the inner shell, it is located directly near the seeds (several or one). Mesocarpy is the middle shell, exocarpy is the external. These three structures combine into the pericarp, or pericarp. In most cases, exocarpy is represented by the skin (in fruits) or shell (in nuts). Endocarpy is most often the part of the fetus that is eaten by animals and humans. And mesocarpy can be seen, for example, in the form of a white shell between the pulp and skin of an orange. However, there are exceptions to these rules. In apples, for example, endocarp is presented in the form of transparent plates near the seeds, and the flesh is mesocarp.
The fruits are different
They are divided into several groups, depending on their appearance and some structural features. Fruits are nuts, cherries, and acorns - they all have a similar structure, but at the same time there are many differences.
Classification
The fruits of plants are divided into two large groups: dry and juicy. The second, unlike the first, have flesh. Dry are divided into multi-seeded (box-shaped) and single-seeded (nut-shaped), juicy - into bone-shaped and berry-shaped. Each of these groups combines different types of fruits. There are a lot of them. So, box-shaped include such fruits of plants as bean, pod, pod, pouch, leaflet, box. Nuts are represented by a kernel, lionfish, achene, nut and nut. Only juicy drupe belongs to the drupes. Berry fruits combine such fruits as a berry, pumpkin, apple. Let's look at each of them in more detail.
Dry box-shaped
The first representatives of this group are beans. This fruit is found in all plants of the legume family. It consists of one carpel, has two seams along which it can be opened. This is a one-nested fetus. Plants with beans: beans, peas, lupins, lentils, mimosa, clover, wisteria.
The next type is pods and pods. These are the fruits of the vegetables of the cruciferous family, to which cabbage, mustard, lettuce, turnip, horseradish and others belong. It differs from the previous one in that it is two-caved, has two carpels. The box is also a dry box-shaped fruit. It usually contains a very large number of small seeds. The following plants form such a fruit: poppy, henbane, cloves, dope. Its structure may have one or more carpels. According to the method of opening the boxes can also vary. For example, poppies have holes in poppies, whitewashed caps have lids, datura have sashes, cloves have cloves.
Dry nut fruits
The first among them should, of course, be the nut.
Its main difference is a woody outer shell. Such fruits are possessed by such plants as walnuts, pterocaria, Californian, black, Manchurian nuts. Hazel forms similar fruits - these are nuts, they are smaller and have a softer shell. Also, the achene belongs to this group. This fruit has a leathery pericarp, with which seeds are not spoiled. It is formed by many complex flowering plants, the most common and widely known of which is sunflower.
Also these are asters, daisies, marigolds, wormwood, dandelion, teasel and many others. Grain also belongs to this group of fruits. It is characteristic of plants of
the cereal family, which combines such crops as rye, wheat, millet, bluegrass, bamboo, feather grass and others. This type of fetus is characterized by a leathery pericarp, which grows together with endocarp.
The next species is lionfish. These are the fruits of maple tree, as well as ash. It has a pericarp with a leathery membranous pterygoid outgrowth, due to which the seeds can spread with the wind to a farther distance from the parent tree.
Juicy berry-like
First of all, apples belong to them. They are characterized by membranous chambers in which seeds are located, and the flesh is formed in the process of fusion of the tubule and ovary of the flower. No, such fruits are formed not only by the apple tree, but also all plants of the pink family: pear, mountain ash, hawthorn, quince and others. Also in this group are berries that have a fleshy, juicy pericarp. They are possessed by such plants: currants, blueberries, lingonberries, gooseberries, tomatoes, kiwi, eggplant, banana and others. Contrary to popular belief, cherries and raspberries are not berries, but drupe. False berries include strawberries and strawberries, as well as rose hips - these are collections of fruits - multi-noses.
In the first two, the real fruits (nuts) are outside this structure (white dots), and in the latter - inside. A collection of nuts are also birch catkins. Pumpkin also belongs to juicy berry-shaped. It has a juicy flesh, but a woody exocarp. This fruit has a pumpkin, watermelon (the fact that it is a berry is also a delusion),
melon, and cucumber.Skeleton-like
It is also a subgroup of juicy fruits. Its only representative is drupe. It is characterized by the fact that the seeds of fruits of this type are inside the seed, located under the pericarp, having a hard outer shell and intended for additional protection. Drupe can contain either one or several seeds. Examples of this type: plum, cherry, coconut, peach, apricot, viburnum. There are also complex fruits formed by several drupes. This is raspberry, blackberry.
What protects the pericarp?
Under these three shells is one or more seeds. Let's look at their structure. All flowering plants are divided into monocotyledonous and dicotyledonous - this depends on how many cotyledons have their seeds.
Seeds of monocotyledonous plants consist of a single cotyledon, bud, stem, root, of which, in fact, a new plant is formed, endosperm and seed peel, usually fused with pericarp. Fruits with this type of seed are, for example, pods and streams. It is also sometimes a box (in a tulip, lily), less often - a berry.
The seeds of dicotyledonous plants are distinguished by the presence of two cotyledons. Also, their structure differs from the previous ones in that their seed peel almost never grows together with the pericarp. These seeds can be found in fruits such as drupes, apples, beans, achenes, and others.
Methods of distribution of fruits and seeds
They can be distributed with the help of any “intermediary” or without it.
Thus, some plants throw their seeds out of opened fruits (most often beans). Also, the fruits can simply fall under the influence of gravity from their weight. But more often they are carried with the help of wind, animals or people, as well as water. For this, the fruits often have additional devices, for example, dandelion pappus (fluffs growing from the pericarp, with the help of which they spread with the wind).