What is in the flower seed. What is a seed made of?

.(Source: "Biological Encyclopedic Dictionary." Chief editor M. S. Gilyarov; Editorial board: A. A. Babaev, G. G. Vinberg, G. A. Zavarzin and others - 2nd ed., corrected . - M .: Sov. Encyclopedia, 1986.)

seed

.(Source: "Biology. Modern Illustrated Encyclopedia." Editor-in-Chief A.P. Gorkin; M.: Rosmen, 2006.)

Synonyms:

See what "SEED" is in other dictionaries:

Wed a substance containing an animal or vegetable germ. From the seed the tree, from the tree the fruit, from the fruit the seed. As is the seed, so is the tribe, and vice versa. Every seed brings its past. | Descendants, descending generation. Everyone, like a seed ... ... Dahl's Explanatory Dictionary

Seeds of cycads are large. Elliptical, oblong ovoid or spherical in shape, they are usually 3-4 cm long and 2-3 cm thick. But some species have either smaller or larger seeds. So, zamia seeds ... ... Biological Encyclopedia

SEED, genus. and dates. seed, seed, seed, pl. seeds, seeds, cf. 1. The reproductive organ of a plant, the grain from which a new plant develops. The seed develops from the ovule. The nucleus of the seed contains the embryo. The plant produced seeds. Selective ... ... Explanatory Dictionary of Ushakov

Grain, bone. Cm … Synonym dictionary

Modern Encyclopedia

In botany, the organ of reproduction, settling and experiencing adverse conditions in seed plants. It develops from the ovule, usually after fertilization. In the seed, the embryo, the peel (shell) and, in many plants, tissues with spare ... ... Big Encyclopedic Dictionary

Seed ... The initial part of compound words, introducing the meaning of the word: seed 1., 4. (cotyledons, ejaculation, ovule, etc.). Explanatory Dictionary of Efremova. T. F. Efremova. 2000... Modern explanatory dictionary of the Russian language Efremova

Seed- (botanical), the organ of reproduction and settlement in seed plants. It develops from the ovule, usually after fertilization. In angiosperms, the seed is enclosed in the fruit, in gymnosperms it is formed openly on the seed scales and ... ... Illustrated Encyclopedic Dictionary

SEED, part of flowering plants (angiosperms) containing the GEM and food reserves. It is formed in the OVARY by FERTILIZATION of the female GAMETE. Nutrients can be stored in a special tissue called ENDOSPERM, or ... ... Scientific and technical encyclopedic dictionary

SEED, me, pl. mena, myan, menam, cf. 1. Organ of reproduction in plants, grain. Hemp s. 2. pl. Grains intended for sowing. Garden seeds. Leave the plant to seed (to get seeds from it for sowing). 3. trans., what. ... ... Explanatory dictionary of Ozhegov

The seed is a plant reproductive organ that develops after fertilization from the ovule.

During the formation of a seed and a fetus, one of the sperm fuses with the egg, forming a diploid zygote. (fertilized egg). Subsequently, the zygote divides many times, and as a result, a multicellular embryo of the plant develops. The central cell, which has merged with the second sperm, also divides many times, but the second embryo does not appear. A special tissue is formed - the endosperm. The endosperm cells accumulate reserves of nutrients necessary for the development of the embryo. The integuments of the ovule grow and turn into a seed coat.

Thus, as a result of double fertilization, a seed is formed, which consists of an embryo, a storage tissue (endosperm) and a seed coat. From the wall of the ovary, the wall of the fruit, called the pericarp, is formed.

Seed types

1. with endosperm (seed consists of three parts: seed coat, endosperm and germ. Seed with endosperm is inherent in monocotyledons, but can also occur in dicotyledons - poppy, solanaceous, umbellate);

2. with endosperm and perisperm (usually a rare type of structure, when the seed contains an embryo, endosperm and perisperm. It is typical for lotus, nutmeg);

3. with perisperm (the endosperm is completely consumed for the formation of the embryo. Seeds of this type are characteristic of cloves);

1. without endosperm and perisperm (the embryo occupies the entire cavity of the embryo sac, and reserve nutrients accumulate in the cotyledons of the embryo. Together, the seed consists of two parts: the seed coat and the embryo. This structure of the seed is characteristic of legumes, pumpkin, rosaceous, walnut, beech, etc.)

Perisperm - Storage diploid tissue of the seed, in which nutrients are deposited. Arises from nucellus.

Endosperm - Large cell storage tissue, the main source of nutrition for the developing embryo. First, it actively transfers the substances coming from the mother's body to the embryo, and then serves as a reservoir for depositing nutrients.

Rice. seeds

16. Classification of fruits. infructescence .

The fruit is an organ of reproduction of angiosperms, formed from a single flower and serving for the formation, protection and distribution of the seeds enclosed in it. Many fruits are valuable foodstuffs, raw materials for the production of medicinal, coloring substances, etc.

Fruit classification

In most classifications, fruits are usually divided into real(formed from an overgrown ovary) and false(other bodies also take part in their formation).

Real fruits are divided into simple(formed from one pistil) and complex(arising from a polynomial apocarpous gynoecium).

Simple are divided according to the consistency of the pericarp into dry And juicy.

Among the dry distinguish single-seeded(for example, grain, nut) and polysperms. Multi-seeded fruits are divided into openable (bean, capsule, pouch, pod, etc.) and non-opening. Non-opening dry multi-seeded fruits are divided into articulated (articulated bean, articulated pod) and fractional (vislocarp, two-winged, etc.)

Among the juicy fruits are also distinguished multi-seeded ( pumpkin, apple, berry) and single-seeded(drupe).

Complex ones are called based on the names of simple fruits (multi-drupe, multi-nut, etc.).

Unlike the fruit (simple or complex), the infructescence is formed not from one flower, but from the whole inflorescence or its parts. In any case, in addition to flowers, the axis of the inflorescence takes part in the formation of the inflorescence. The infructescence is a product of modification (after fertilization) not only of flowers, but also of the axes of the inflorescence. In typical cases, the seed imitates the fetus and corresponds to it functionally. A classic example is the fruit of a pineapple.

17 ,Vegetative propagation of plants and its biological meaning Vegetative propagation of plants(from lat. vegetativas- vegetable) is the reproduction of plants with the help of vegetative organs (root, stem, leaf) or their parts. Vegetative propagation of plants is based on the phenomenon of regeneration. During this method of reproduction, all properties and hereditary qualities in the offspring are fully preserved.

There are natural and artificial vegetative reproduction. Natural reproduction occurs constantly in nature through the impossibility or difficulty of seed reproduction. It is based on the separation from the mother plant of viable vegetative organs or parts capable of restoring the whole plant from its part as a result of regeneration. The whole set of individuals obtained in this way is called clone. Clone(from the Greek. clon - sprout, branch) - a population of cells or individuals, which is formed as a result of asexual division from one cell or individual. Vegetative propagation of plants in nature carried out by:

Divisions (unicellular);

Root sprouts (cherry, apple, raspberry, blackberry, wild rose);

Corenebulbs (orchid, dahlias);

Layering (currant, gooseberry);

Mustache (strawberry, buttercup creeping);

Rootstocks (wheatgrass, reed);

Tubers (potatoes);

Bulbs (tulip, onion, garlic);

Brood buds on leaves (briofilum).

The biological significance of vegetative propagation: a) one of the adaptations for the formation of offspring where there are no favorable conditions for sexual reproduction; b) the genotype of the parental form is repeated in the descendants, which is important for preserving the traits of the variety; c) one of the ways to preserve valuable varietal characteristics and properties; d) in case of vegetative reproduction, the plant can be stored under the conditions of impossibility of seed reproduction; e) the preferred method of propagating ornamental plants; f) when grafted, resistance to external conditions increases in the graft. The disadvantages of vegetative propagation should also be noted: a) negative traits are transmitted b) diseases of the mother's body are transmitted.

18. Asexual reproduction, its role and forms Reproduction is a universal property of all living organisms, the ability to reproduce their own kind. With its help, species and life in general are preserved in time. The life of cells is much shorter than the life of the organism itself, therefore its existence is supported only by cell reproduction. There are two types of reproduction - asexual and sexual. During asexual reproduction, the main cellular mechanism that provides an increase in the number of cells is mitosis. The parent is one individual. The offspring is an exact genetic copy of the parent material. 1) The biological role of asexual reproduction Maintaining fitness enhances the importance of stabilizing natural selection; provides fast reproduction rates; used in practical selection. 2) Forms of asexual reproduction In unicellular organisms, the following forms of asexual reproduction are distinguished: division, endogony, schizogony and budding, sporulation. Division is typical for amoeba, ciliates, flagellates. First, the mitotic division of the nucleus occurs, then the cytoplasm is divided in half by an ever deeper constriction. In this case, daughter cells receive approximately the same amount of cytoplasm and organelles. Endogony (internal budding) is characteristic of Toxoplasma. With the formation of two daughter individuals, the mother gives only two descendants. But there may be internal multiple budding, leading to schizogony. It occurs in sporozoans (malarial plasmodium), etc. There is a multiple division of the nucleus without cytokinesis. From one cell, a lot of daughters are formed. Budding (in bacteria, yeast fungi, etc.). At the same time, a small tubercle containing a daughter nucleus (nucleoid) is initially formed on the mother cell. The kidney grows, reaches the size of the mother, and then separates from it. Sporulation (in higher spore plants: mosses, ferns, club mosses, horsetails, algae). The daughter organism develops from specialized cells - spores containing a haploid set of chromosomes. 3) Vegetative form of reproduction Characteristic of multicellular organisms. In this case, a new organism is formed from a group of cells that separate from the parent organism. Plants reproduce by tubers, rhizomes, bulbs, root tubers, root crops, root shoots, layering, cuttings, brood buds, leaves. In animals, vegetative reproduction occurs in the lowest organized forms. Ciliary worms are divided into two parts, and in each of them the missing organs are restored due to disordered cell division. Annelids can regenerate an entire organism from a single segment. This type of division underlies regeneration - restoration of lost tissues and body parts (in annelids, lizards, salamanders)

19 Sexual reproduction - associated with the fusion of specialized sex cells - gametes with the formation of a zygote. Gametes may be the same or different morphologically. Isogamy - fusion of identical gametes; heterogamy - the fusion of gametes of different sizes; oogamy - the fusion of a motile spermatozoon with a large immobile egg.

For some groups of plants, alternation of generations is characteristic, in which the sexual generation produces germ cells (gametophyte), and the non-sexual generation produces spores (sporophyte).

Fertilization - this is the union of the nuclei of male and female germ cells - gametes, leading to the formation of a zygote and the subsequent development of a new (daughter) organism from it.

Gamete is a reproductive cell with a single (or haploid) set of chromosomes involved in sexual reproduction. That is, in other words, the egg and sperm are gametes with a set of chromosomes of 23 each.

Zygote is the result of the fusion of two gametes. That is, a zygote is formed as a result of the fusion of a female egg and a male sperm. Subsequently, it develops into an individual (in our case, into a person) with the hereditary characteristics of both organisms of the parents.

isogamy

If the merging gametes do not morphologically differ from each other in size, structure and chromosome set, then they are called isogametes, or asexual gametes. Such gametes are motile, may carry flagella or be amoeboid. Isogamy is typical of many algae.

Definition of the term "seed" in botany

Although the seed is often described (including in authoritative sources) as the "organ of seed reproduction of plants" (less often - the "organ of sexual reproduction of plants"), the seed is not an organ in the usual sense of this term, since it combines the structures of two (in gymnosperms - three) different generations of the life cycle. The organs of sexual reproduction (genital organs, gametangia) in gymnosperms are represented by archegonia, and in flowering plants they are reduced. More justified is the definition of a seed as a "rudimentary plant" (it is given by many school textbooks of botany); this definition emphasizes that a new generation (sporophyte) of the plant will develop from the seed. At the same time, the remaining parts of the seed, except for the embryo, can be considered additional structures (organs) that ensure the development of the embryo.

Seed structure

The structure of gymnosperms

The seed develops on the surface of the seed scale. It is a multicellular structure that combines storage tissue - endosperm, embryo and a special protective cover (seed peel). Before fertilization, the central part of the ovule contains the nucellus, which is gradually replaced by the endosperm. The endosperm is haploid and is formed from the tissues of the female gametophyte.

Endosperm

Endosperm is the tissue contained within the seed, usually surrounding the embryo and supplying it with nutrients during development. In gymnosperms, the endosperm is the tissue of the female gametophyte. Often in the early stages of development, it has a syncytial structure, later cell walls form in it. Endosperm cells are initially haploid but may become polyploid. In flowering plants, the endosperm is usually formed during double fertilization as a result of the fusion of the central cell (central nucleus) of the embryo sac with one of the sperm. In many flowering cells, the endosperm is triploid. In a water lily, the endosperm is formed by the fusion of sperm with a haploid cell of the embryo sac, so that its nuclei are diploid. In many flower nuclei, the endosperm has a chromosome set of more than 3n (up to 15n).

Perisperm

Main article: Perisperm

The perisperm is similar in function to the endosperm, but has a diploid set of chromosomes, contains a small amount of proteins, mainly starch, and sometimes fats. It can play the role of the main storage tissue both independently and along with the endosperm.

germ

Resting state

Seed germination

Oxygen

Moisture

Stratification

Scarification

It is assumed that the seeds of some plants (for example, calvaria Sideroxylon grandiflorum) cannot germinate in nature without passing through the intestines of birds. So, the seeds of calvaria could be germinated only after they passed through the intestines of domestic turkeys or were treated with polishing paste.

Some seeds require both scarification and stratification. And sometimes (hawthorn) most of the seeds germinate after scarification and double stratification, that is, after two winter dormant periods.

Light

Seed spread

Self-spreading of seeds (autochory)

The seeds of many plants fall to the ground next to the mother plant after the fruit has opened. Sometimes, when the fruit is opened, the seeds are ejected with force, scattering over a certain distance. Self-scattering of seeds is typical for plants such as small-flowered touchy, common oxalis.

wind spread

The seeds of many plants are dispersed by the wind (anemochory). These are, for example, ordinary pine seeds, equipped with a wing, seeds of plants of the genera Poplar and Willow, covered with hairs (“poplar fluff”), small dusty orchid seeds.

Spread by water (hydrochory)

Fruits and seeds of not only aquatic, but also some terrestrial plants are distributed by water. Alder often grows along the banks of rivers; its fruits, falling into the water, do not sink. The current carries them away from the mother plants. The fruits of the coconut palm are carried from one island to another by sea currents.

Spread by animals

Distribution by animals is zoochory. Plant seeds can be dispersed by animals on the body (usually with fruits), by passage through the intestinal tract, and by dispersal with loss of seeds.

On the body, seeds and single-seeded fruits are usually carried by birds and mammals. So, mammals can carry on wool the fruitlets of gravilat, succession, agrimony and many other plants with hooks, hairs and trailers. Also sticky seeds of mistletoe, water lilies, etc. can spread on the body of birds and mammals.

Through the intestines of birds and mammals, after eating the fruits, they pass, without losing their germination, the seeds of plants such as warty euonymus, hawthorn, raspberries and many others.

While making stocks in pantries, squirrels, chipmunks, jays and nutcrackers lose part of the seeds or do not find part of the pantries, contributing to the spread of Siberian pine and oak seeds.

A particular mode of seed dispersal by animals is myrmecochory. Myrmecochory is the dispersal of seeds by ants. The seeds of some plants have nutritional appendages attractive to ants - elaiosomes. Myrmecochore plants of central Russia - fragrant violet, European hoof, hairy ozhika and many others; some of them are distributed exclusively by ants.

The role of seeds in nature and human life

Many organisms (from fungi and bacteria to birds and mammals) feed heavily, and sometimes exclusively, on seeds. Seeds form the basis of the food of such animals as some insects and their larvae (for example, reaper ants), granivorous birds, rodents (chipmunks, squirrels, hamsters, etc.).

Since the beginning of agriculture in most regions of the world, the basis of the human diet has also been seeds, primarily of cultivated cereals (wheat, rice, corn, etc.). The main nutrient with which humanity receives the most calories is starch, found in cereal seeds. An important source of proteins for humanity are also the seeds of leguminous plants - soybeans, beans, etc. Seeds are the main source of vegetable oils, which are extracted from sunflower seeds, rapeseed, corn, flax and many other oilseeds.

Literature

• Melikyan A. P., Nikolaeva M. G., Komar G. A. Seed // Plant life: in 6 vols. / Ed. A. L. Takhtadzhyan. - M .: Education, 1980. - V. 5. Part 1. Flowering plants. Dicotyledons: magnoliids, ranunculids, hamamelidids, caryophyllids. - S. 84-91.
• Danovich K. N., Sobolev A. M., Zhdanova L. P., Illi I. E., Nikolaeva M. G., Askochenskaya N. A., Obrucheva N. V., Khavkin E. E. Physiology of seeds / Academy of Sciences of the USSR; Scientific council on problems of physiology and biochemistry of plants; Order of the Red Banner of Labor Institute of Plant Physiology. K. A. Timiryazev; Rep. ed. b. n. A. A. Prokofiev. - M .: Nauka, 1982. - 318 p.

Notes

Links

	seed in Wiktionary
	Seed at Wikimedia Commons

• plant seed- article from the Great Soviet Encyclopedia
• Seed Science Research is an international journal dedicated to the study of seeds. (Retrieved January 29, 2011)

The seeds of flowering plants are diverse in shape and size: they can reach several tens of centimeters (palms) and be almost indistinguishable (orchids, broomrape).

In shape - spherical, elongated-spherical, cylindrical. Thanks to this shape, minimal contact of the seed surface with the environment is ensured. This allows the seeds to more easily tolerate adverse conditions.

The structure of the seed

Outside, the seed is covered with a seed coat. The seed surface is usually smooth, but may be rough, with spines, ribs, hairs, papillae, and other outgrowths of the seed coat. All these formations seed dispersal adaptation.

On the surface of the seeds, a scar and pollen inlet are visible. Scar- a trace from the seed stalk, with the help of which the seed was attached to the wall of the ovary, pollen entry stored as a small hole in the seed coat.

Under the skin is the main part of the seed - embryo. Many plants have specialized storage tissue in their seeds - endosperm. In those seeds where there is no endosperm, nutrients are deposited in the cotyledons of the embryo.

The structure of the seeds of monocots and dicots is not the same. A typical dicotyledonous plant is beans, a monocotyledonous plant is rye.

The main difference in the structure of the seeds of monocots and dicots is the presence of two cotyledons in the embryo in dicots and one in monocots.

Their functions are different: in the seeds of dicotyledonous cotyledons contain nutrients, they are thick, fleshy (beans).

In monocots, the only cotyledon is the scutellum - a thin plate located between the embryo and the endosperm of the seed and tightly adjacent to the endosperm (rye). During seed germination, the cells of the shield absorb nutrients from the endosperm and supply them to the embryo. The second cotyledon is reduced or absent.

seed germination conditions

Seeds of flowering plants can endure unfavorable conditions for a long time, preserving the embryo. Seeds with a living embryo can germinate and give rise to a new plant, they are called viable. Seeds with a dead embryo become dissimilar they cannot grow.

For seed germination, a set of favorable conditions is necessary: ​​the presence of a certain temperature, water, and air access.

Temperature. The range of temperature fluctuations at which seeds can germinate depends on their geographical origin. For "northerners" need a lower temperature than for people from southern countries. So, wheat seeds germinate at temperatures from 0° to +1°C, and corn - at + 12°C. This must be taken into account when setting the timing of sowing.

The second condition for seed germination is presence of water. Only well-moistened seeds can germinate. The need for water to swell the seeds depends on the composition of the nutrients. The largest amount of water is absorbed by seeds rich in proteins (peas, beans), the smallest - rich in fats (sunflower).

Water, penetrating through the seminal inlet (pollen inlet) and through the seed coat, brings the seed out of dormancy. In it, first of all, breathing increases sharply and enzymes are activated. Under the influence of enzymes, reserve nutrients are converted into a mobile, easily digestible form. Fats and starches are converted into organic acids and sugars, while proteins are converted into amino acids.

seed breath

For active respiration of swelling seeds, oxygen access is necessary. During respiration, heat is released. In raw seeds, respiration is more active than in dry ones. If raw seeds are folded in a thick layer, they quickly warm up, their embryos die. Therefore, only dry seeds are stored for storage and stored in well-ventilated areas. For sowing, larger and full-fledged seeds should be selected without admixture of weed seeds.

Seeds are cleaned and sorted on sorting and grain cleaning machines. Before sowing, the quality of seeds is checked: germination, viability, moisture, infestation with pests and diseases.

When sowing, it is necessary to take into account the depth of seed embedding in the soil. Small seeds should be sown at a depth of 1-2 cm (onions, carrots, dill), large seeds - at 4-5 cm (beans, pumpkin). The depth of seed placement also depends on the type of soil. In sandy soils, they sow a little deeper, and in clay soils, they are sown smaller. In the presence of a complex of favorable conditions, germinating seeds begin to germinate and give rise to new plants. Young plants that develop from the embryo of a seed are called seedlings.

In the seeds of any plant, germination begins with the elongation of the germinal root and its exit through the pollen entrance. At the time of germination, the embryo feeds heterotrophically, using the nutrient reserves contained in the seed.

In some plants, during germination, the cotyledons are carried above the soil surface and become the first assimilation leaves. This elevated sprouting type (pumpkin, maple). In others, the cotyledons remain underground and are the source of nutrition for the seedling (pea). Autotrophic nutrition begins after the appearance of shoots with green leaves above the ground. This underground germination type.

Definition of the term "seed" in botany

Although the seed is often described (including in authoritative sources) as the "organ of seed reproduction of plants" (less often - the "organ of sexual reproduction of plants"), the seed is not an organ in the usual sense of this term, since it combines the structures of two (in gymnosperms - three) different generations of the life cycle. The organs of sexual reproduction (genital organs, gametangia) in gymnosperms are represented by archegonia, and in flowering plants they are reduced. More justified is the definition of a seed as a "rudimentary plant" (it is given by many school textbooks of botany); this definition emphasizes that a new generation (sporophyte) of the plant will develop from the seed. At the same time, the remaining parts of the seed, except for the embryo, can be considered additional structures (organs) that ensure the development of the embryo.

Seed structure

The structure of gymnosperms

The seed develops on the surface of the seed scale. It is a multicellular structure that combines storage tissue - endosperm, embryo and a special protective cover (seed peel). Before fertilization, the central part of the ovule contains the nucellus, which is gradually replaced by the endosperm. The endosperm is haploid and is formed from the tissues of the female gametophyte.

Endosperm

Endosperm is the tissue contained within the seed, usually surrounding the embryo and supplying it with nutrients during development. In gymnosperms, the endosperm is the tissue of the female gametophyte. Often in the early stages of development, it has a syncytial structure, later cell walls form in it. Endosperm cells are initially haploid but may become polyploid. In flowering plants, the endosperm is usually formed during double fertilization as a result of the fusion of the central cell (central nucleus) of the embryo sac with one of the sperm. In many flowering cells, the endosperm is triploid. In a water lily, the endosperm is formed by the fusion of sperm with a haploid cell of the embryo sac, so that its nuclei are diploid. In many flower nuclei, the endosperm has a chromosome set of more than 3n (up to 15n).

Perisperm

Main article: Perisperm

The perisperm is similar in function to the endosperm, but has a diploid set of chromosomes, contains a small amount of proteins, mainly starch, and sometimes fats. It can play the role of the main storage tissue both independently and along with the endosperm.

germ

Resting state

Seed germination

Oxygen

Moisture

Stratification

Scarification

It is assumed that the seeds of some plants (for example, calvaria Sideroxylon grandiflorum) cannot germinate in nature without passing through the intestines of birds. So, the seeds of calvaria could be germinated only after they passed through the intestines of domestic turkeys or were treated with polishing paste.

Some seeds require both scarification and stratification. And sometimes (hawthorn) most of the seeds germinate after scarification and double stratification, that is, after two winter dormant periods.

Light

Seed spread

Self-spreading of seeds (autochory)

The seeds of many plants fall to the ground next to the mother plant after the fruit has opened. Sometimes, when the fruit is opened, the seeds are ejected with force, scattering over a certain distance. Self-scattering of seeds is typical for plants such as small-flowered touchy, common oxalis.

wind spread

The seeds of many plants are dispersed by the wind (anemochory). These are, for example, ordinary pine seeds, equipped with a wing, seeds of plants of the genera Poplar and Willow, covered with hairs (“poplar fluff”), small dusty orchid seeds.

Spread by water (hydrochory)

Fruits and seeds of not only aquatic, but also some terrestrial plants are distributed by water. Alder often grows along the banks of rivers; its fruits, falling into the water, do not sink. The current carries them away from the mother plants. The fruits of the coconut palm are carried from one island to another by sea currents.

Spread by animals

Distribution by animals is zoochory. Plant seeds can be dispersed by animals on the body (usually with fruits), by passage through the intestinal tract, and by dispersal with loss of seeds.

On the body, seeds and single-seeded fruits are usually carried by birds and mammals. So, mammals can carry on wool the fruitlets of gravilat, succession, agrimony and many other plants with hooks, hairs and trailers. Also sticky seeds of mistletoe, water lilies, etc. can spread on the body of birds and mammals.

Through the intestines of birds and mammals, after eating the fruits, they pass, without losing their germination, the seeds of plants such as warty euonymus, hawthorn, raspberries and many others.

While making stocks in pantries, squirrels, chipmunks, jays and nutcrackers lose part of the seeds or do not find part of the pantries, contributing to the spread of Siberian pine and oak seeds.

A particular mode of seed dispersal by animals is myrmecochory. Myrmecochory is the dispersal of seeds by ants. The seeds of some plants have nutritional appendages attractive to ants - elaiosomes. Myrmecochore plants of central Russia - fragrant violet, European hoof, hairy ozhika and many others; some of them are distributed exclusively by ants.

The role of seeds in nature and human life

Many organisms (from fungi and bacteria to birds and mammals) feed heavily, and sometimes exclusively, on seeds. Seeds form the basis of the food of such animals as some insects and their larvae (for example, reaper ants), granivorous birds, rodents (chipmunks, squirrels, hamsters, etc.).

Since the beginning of agriculture in most regions of the world, the basis of the human diet has also been seeds, primarily of cultivated cereals (wheat, rice, corn, etc.). The main nutrient with which humanity receives the most calories is starch, found in cereal seeds. An important source of proteins for humanity are also the seeds of leguminous plants - soybeans, beans, etc. Seeds are the main source of vegetable oils, which are extracted from sunflower seeds, rapeseed, corn, flax and many other oilseeds.

Literature

• Melikyan A. P., Nikolaeva M. G., Komar G. A. Seed // Plant life: in 6 vols. / Ed. A. L. Takhtadzhyan. - M .: Education, 1980. - V. 5. Part 1. Flowering plants. Dicotyledons: magnoliids, ranunculids, hamamelidids, caryophyllids. - S. 84-91.
• Danovich K. N., Sobolev A. M., Zhdanova L. P., Illi I. E., Nikolaeva M. G., Askochenskaya N. A., Obrucheva N. V., Khavkin E. E. Physiology of seeds / Academy of Sciences of the USSR; Scientific council on problems of physiology and biochemistry of plants; Order of the Red Banner of Labor Institute of Plant Physiology. K. A. Timiryazev; Rep. ed. b. n. A. A. Prokofiev. - M .: Nauka, 1982. - 318 p.

Notes

Links

	seed in Wiktionary
	Seed at Wikimedia Commons

• plant seed- article from the Great Soviet Encyclopedia
• Seed Science Research is an international journal dedicated to the study of seeds. (Retrieved January 29, 2011)