Fruits and seeds of plants are consonant concepts. Both of these parts of plants serve the great function of reproducing a living organism.
Fruit -is the organ of a flowering plant, which consists of a seed surrounded by a pericarp. The fruit is a modified flower. It appears as a result of Navashin's double fertilization. One flower produces one fruit. Its main function is to create optimal conditions for the formation, protection and subsequent distribution of the semen contained in it. The study of one organ of angiosperms is the science of carpology.
The fruit is formed primarily from the walls of the ovary (cherry, peach, plum), but in some plants other parts of the flower are involved in the formation of this organ - the flower bed, the base of the stamens, sepals and petals (tomato, apple, strawberry). In any fruit, two parts are clearly expressed: the three-layer outer (it is the pericarp or pericarp) and the inner, which includes the embryo of the future plant and the endosperm with nutrients.
Fruits are divided into real, formed with the help of the ovary, and false - formed with the participation of other organs of the flower. Also, fruits can be simple (peach) and complex (raspberries, rose hips), depending on the number of pistils that took part in their formation. According to the state of the pericarp, the fruits are divided into dry (poppy, bean, hazelnuts, sunflower) and juicy (watermelon, pear, pomegranate). In addition, dry fruits can be boll-shaped, many-seeded, or nut-shaped, single-seeded. The juicy fruits are known as berries and drupes.
The plant pericarp contains a certain amount of vitamins, microelements, fats, which make these plant organs irreplaceable food products for animals and humans.
Seed is the formation of angiosperms and gymnosperms, which contains the embryo of the future plant and a certain supply of nutrients necessary for its development. From above, the seed is covered with a protective layer or skin. Seeds of gymnosperms and angiosperms differ morphologically.
Seeds of gymnosperms are multicellular. They consist of an embryo, endosperm, and are covered with a seed coat. The endosperm has a haploid set of chromosomes and develops from the female gametophyte on the surface of the seed scale.
The seeds of angiosperms are covered with a seed coat formed from the ovule. The bulk and volume of the semen is occupied by the endosperm, formed by the fusion of the central nucleus with one sperm. It has from 3 to 15 sets of chromosomes. Along with the endosperm, the perisperm is found in the seed of angiosperms. It is formed from nucellus. It is low in protein, high in starch and fat. The embryo uses this reserve by germinating. It contains a diploid set of chromosomes. The "pearl" of the seed, for the sake of which all this fuss with endospermia and perispermia was started, is the embryo, the "embryo" of the future plant.
An embryo is formed during the double fertilization of Navashin in the embryo sac, as a result of the fusion of one sperm with an egg. This produces a zygote, which later develops into an embryo. It is from the seed germ that the formation of the seed begins.
Seeds have the property of "germination", can be dormant, spread automatically, by wind, animals or water, like coconuts.
- Seeds are characteristic of angiosperms and gymnosperms, the fruit is a feature of angiosperms of flowering plants.
- Seeds are formed from the ovules or in the embryo sac, the fruits in most cases are formed from the walls of the ovary.
- The seed, in the case of angiosperms, is "hidden" in the middle of the fruit.
- A single seed can survive longer with retention of germination than a fruit.