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). When the seed germinates, 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. it 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. it underground germination type.
Seed- This is a reproductive organ, which in angiosperms is formed from the ovule, usually after double fertilization.
Seed structure. Initially, the seed is inside the fruit, which protects it until it germinates. Each seed consists of a seed coat, an embryo and storage tissues.
Testa develops from integuments (covers) of the ovule, so it is diploid (2n). It is multi-layered and is always present in the seed. The thickness and density of the seed coat is related to the characteristics of the pericarp, so it can be soft, leathery, membranous or hard (woody). The seed coat protects the embryo from mechanical damage, drying out and premature germination. In addition, it can promote seed germination.
germ is a plant in its infancy and consists of germinal root, stalk, cotyledons and buds. The embryo develops from a zygote formed as a result of the fusion of sperm with an egg (2n).
Storage tissues The seeds are endosperm and perisperm. Endosperm is formed as a result of double fertilization when the central nucleus of the embryo sac (2n) merges with the second sperm (1n). Therefore, the endosperm consists of triploid cells (3n). Perisperm is a derivative of nucellus and consists of cells with a diploid set of chromosomes.
Seed types. The classification of seeds is based on the location of reserve nutrients. Distinguish four types of seeds (Fig. 22):
Rice. 22. Types of seeds:
BUT- seeds with endosperm that surrounds the embryo (poppy);
B- seeds with endosperm adjacent to the embryo (wheat); AT- seeds with a small endosperm (surrounds the embryo) and powerful perisperm (pepper); G– seeds with perisperm (cockle);
D- seeds with reserve substances deposited in the cotyledons of the embryo (peas); 1 - seed coat; 2 - endosperm; 3 - spine; 4 - stalk; 5 - kidney; 6 - cotyledons; 7 - pericarp;
8 – perisperm
1) seeds with endosperm mainly characteristic of seeds of the class of monocots, as well as some dicots (nightshade, celery, poppy); reserve nutrients are localized in the endosperm;
2) seeds with perisperm characteristic of clove, haze, in which the endosperm is completely absorbed in the mature seed, while the perisperm remains and grows; the seed consists of the seed coat, embryo and perisperm;
3) seeds with endosperm and perisperm they have black pepper, a capsule, a water lily, in the seeds of which the endosperm is preserved and the perisperm develops; the seed consists of the seed coat, germ, endosperm and perisperm;
4) seeds without endosperm and without perisperm characteristic of legumes, pumpkin, aster; in the process of development, the embryo completely absorbs the endosperm, so the supply of nutrients is in the cotyledons of the embryo; in this case, the seed consists of the seed coat and the embryo.
Seed structure with endosperm. Such seeds are typical for plants of the class Monocotyledonous, for example, for bluegrass (cereals). In a grain of wheat (swollen seeds) there are ventral side(from the side of the groove) and the opposite - dorsal. On one of the poles of the seed, on the dorsal side, is germ. From the opposite pole there are hairs that hold the grain in the soil and contribute to the supply of water to the endosperm of the seed (Fig. 23).
Rice. 23. The structure of a grain of wheat
(longitudinal section):
1 - hairs; 2 - pericarp fused with the seed coat; 3 - aleurone layer;
4 - a layer of spare starch ( 3 –4 - endosperm); 5 - shield; 6 - epiblast; 7 - a bud with leaves; 8 - coleoptile; 9 - spine;
10 - coleorhiza (root sheath)
Outside, the grain is covered with a thin membranous layer, which is difficult to separate from the inside of the grain. This is a pericarp fused with the seed coat, since the caryopsis is a one-seeded fruit. The structure of the pericarp and seed coat is clearly seen when considering a micropreparation of a cross section of a caryopsis.
The size of the embryo is small compared to the size of the endosperm. This means that the reserve substances are in the endosperm. It consists of two layers: aleurone and reserve starch.
germ has the following parts:
– germinal root with root cap, coleoriza(root sheath);
– germinal stalk and kidney with a cone of growth;
– coleoptile(first germinal leaf) in the form of a colorless cap, with which it pierces the soil layers during germination;
– shield(modified cotyledon) - according to its location in the grain, it forms a partition between the embryo and the endosperm; under the action of enzymes, the shield converts the nutrients of the endosperm into an assimilated form and transfers them to the nutrition of the embryo;
– epiblast located on the opposite side of the shield and is the second reduced cotyledon.
The structure of the seed without endosperm and without perisperm. Such seeds are typical for legumes, pumpkin, aster. Let us consider this type of seed structure using the common bean as an example (seeds swollen in water) (Fig. 24).
Rice. 24. The structure of the common bean seed:
1 - embryonic root; 2 - micropyle; 3 - scar;
4 - seed suture; 5 - seed coat; 6 - kidney;
7 - germinal stalk; 8 – cotyledons
Outside, the seed is covered with a thick seed coat. It can be of different colors. On the inner concave side of the seed, there is a hilum, a micropyle, and a seed suture.
Scar- this is the place where the seed is attached to the seed stalk.
Micropyle- an opening through which water and gases enter the seed. The micropyle is located next to the scar, on the same line.
seed seam- this is a trace of the fusion of the ovule with the peduncle. It is located on the opposite side from the micropyle and also adjoins the scar.
Under the seed coat is embryo. The following parts are distinguished:
– two large cotyledons kidney-shaped; they are germ layers where nutrients are deposited;
– germinal root;
– germinal stalk;
– gemmule covered with germ layers.
The bean seed does not have an endosperm, since the reserve substances are in the cotyledons. It consists of the seed coat and the embryo.
Diverse in size and shape. For example, thousands of small orchid fruits weigh less than a gram, some palm fruits weigh up to 8-15 kg.
For a long time it can endure adverse conditions, be at rest. The embryo remains alive. The seed that can germinate is called viable . Favorable conditions (temperature, humidity, air) are necessary for seed germination. The seed breathes, therefore air (oxygen) access is necessary. During respiration, heat is released. Water enters the seed through the pollen inlet.
A seed consists of an embryo and a supply of nutrients covered seed coat . The surface can be smooth, rough, with spikes, ribs, etc. The seed coat protects the contents of the seed from damage and drying out. On the surface of the seed, one can see scar - a trace from the seed leg and pollen entry . The pollen entrance is preserved as a small hole in the peel.
Nutrients are usually found in the endosperm. The composition of the seed includes organic and inorganic compounds. In many plants, during the maturation of the seed and the formation of the embryo, the endosperm is completely used. Then reserve substances are deposited either in first germ layers or cotyledons (potatoes, beans, peas, pumpkin), in other parts of the seed (cockle).
The number of cotyledons in the seed determined the name of the classes of angiosperms (Monocotyledonous, Dicotyledonous). Seeds of dicotyledonous and monocotyledonous plants have a different structure.
A dicotyledonous seed has two cotyledons, between which the embryo is located. Cotyledons contain nutrients. The embryo consists of the germinal root, stem, bud and leaves. During germination, the cotyledons act as the first leaves.
The seed of monocots has a single cotyledon - shield . This is a thin film located between the endosperm and the embryo. The second cotyledon is reduced. The embryo occupies an insignificant part of the seed and has an embryonic root, stem, bud and leaves. When the seed germinates through the shield, the embryo absorbs nutrients from the endosperm.
In angiosperms, the seed loses its connection with the mother plant and germinates elsewhere. The distribution of fruits and seeds occurs under the influence of various external factors or independently.
Autochory
Autochory (from Greek. autos- myself, choreo- spread) is the ability of plants (lupine, geranium, violet, yellow acacia) to independently distribute fruits and seeds. "Mad Cucumber" when ripe, is capable of throwing seeds with force for many meters.
Anemochory
Anemochory (from Greek. anemos- wind, choreo- to spread) is the spread of fruits with the help of the wind (dandelion, thistle, birch, maple). To do this, the fruits have a number of different adaptations: winged outgrowths (parachutes, hairs, wing-shaped appendages, etc.), light seeds. This allows the wind to pick up the seed. Thus, the fruits do not get enough sleep all together, but gradually. This is a common method among plants.
Ornithochory
Ornithochory (from Greek. ornis- bird, choreo- spread) - the spread of seeds and fruits with the help of birds. Birds can eat fruits, but, having passed through the intestines, the seeds of most plants are not digested, the seed comes out with droppings; or simply move them over long distances and lose them. Some birds can hide fruits in hiding places, where the latter sometimes sprout.
Zoochory
Zoochory (from Greek. zoon- animal, choreo- to spread) is the distribution of fruits and seeds of plants with the help of animals. Animals eat fruits and hatch seeds with droppings, bury fruits in the ground or make caches that are forgotten or not used, carry tenacious fruits on covers.
hydrochoria
hydrochoria (from Greek. hydro- water, choreo- spread) - the distribution of fruits and seeds with the help of water. It is characteristic mainly for aquatic and marsh plants (sedge, water lilies, reeds, etc.).
Anthropochory
Anthropochory (from Greek. anthropos- human, choreo- to spread) is the spread of the seed and fruits by man. A person carries the fruits on clothes, transport, along with food, goods. Sometimes the fruits are thus transferred even to other continents. Often such plants (elodea, ragweed, cyclohena, etc.) multiply rapidly in new places, spread and cause great damage, are weeds that do not have natural enemies.
Importance of fruits and seeds
A person eats a lot of fruits or seeds, feeds domestic animals. From the fruits and seeds of some plants (sunflower, soybeans) a person receives oil. The seeds of oil plants contain from 25 to 80% oil.
Seeds and fruits are used in medicine (raspberry, blackberry, viburnum). Sometimes the fruits and seeds of plants (black henbane, dope, belladonna, etc.) contain poisonous substances. When used in humans, poisoning occurs. Therefore, when using fruits, especially unfamiliar ones, one must be careful. Narcotic substances are produced from the fruits of some plants (hemp, poppy). Most drugs are of plant origin.
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 at the same time. 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. e. 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)
Synopsis keywords: seed, dicots, monocots, seed coat, embryo, endosperm, seed structure, seed germination, fruit, fruit types, fruit functions, types of seed and fruit distribution.
Seed- the organ of seed reproduction and resettlement of plants. It is formed from ovule(ovules) in the ovary of plants. The seed, in most cases, consists of seed coat, embryo and nutrient supply (endosperm).
The main part of the seed is germ. It consists of a root, a stalk, a kidney and two or one cotyledons. This feature underlies the division of all flowering plants into two classes — Dicotyledonous and monocots .
Image from the textbook “Biology. Bacteria, fungi, plants Grade 6 "V.V. Pasechnik - M .: Bustard.
Testa it is formed from the integument of the ovule and performs protective functions; including protects the seed from drying out and, conversely, from premature saturation with moisture. On the seed peel, a scar can be distinguished - the place of attachment of the seed stalk. germ includes root, stalk, bud and one or two cotyledons - formations homologous to leaves. Dicots have two, monocots have one. When germinating above ground, the cotyledons are capable of photosynthesis, while underground they serve as a repository of nutrients. The main root is formed from the root, the main shoot of the plant is formed from the kidney.
| Endosperm- nutritional tissue that develops in the seed of plants ... Consists of triploid cells, in which the genomes of paternal and maternal individuals are combined. E. provides nutrition. substances developing embryo. In some plants, starch grains predominate in it, in others - deposits of oils, etc. In decomp. 85% of flowering plants have a degree of developed E. in mature seeds - almost all monocots, with the exception of most aquatic and marsh plants (family naiads, chastukhovy, etc.), as well as orchids and many others. dicots. However, some dicotyledons lack E. (in legumes, cucurbits, Compositae, cruciferous, as well as in oak, birch, maple, etc.), because at an early stage of development it is absorbed by the growing embryo. (Source: "Biological Encyclopedic Dictionary" - 2nd ed., - M .: Sov. Encyclopedia, 1986.) |
In mature seeds of conifers and most flowering plants endosperm well expressed. However, in representatives of some flowering families, the embryo grows in the seeds so much that it fills them entirely. There is nothing left of the endosperm or nothing at all (legumes, pumpkin, Compositae) or
preserved as a thin layer of cells (apple, almond). In the absence of endosperm, seed reserve substances are deposited in the cells of the embryo, more often in its cotyledons. The endosperm is formed as a result of the so-called and consists of triploid cells.
The seed is within fetus. For example, an apple is a fruit, and the seeds inside the apple are the seed; the watermelon is the fruit, and the bones inside are the seed; the plum is the fruit, and the pit inside is the seed.
The main nutrients in seeds are carbohydrates, mainly: starch (wheat, barley), proteins (beans, peas, beans), fats (sunflower, olive, flax). In addition to organic matter, seeds contain water and minerals.
Under unfavorable conditions, the seeds can stay in resting state . Its size is different for all plants.
seed germination
Seeds need to germinate water, heat and air. With enough water, the seed swells and the dense peel breaks. At a favorable temperature, the enzymes of the seed pass from an inactive state to an active one. Under their action, insoluble reserve substances are converted into soluble: starch into sugar, fats into glycerol and fatty acids, proteins into amino acids .
The influx of nutrients to the embryo brings it out of dormancy, and growth begins. Germinating seeds continuously take in oxygen and give off carbon dioxide, which releases heat. Store seeds in dry, well-ventilated areas. Air access to the seeds should be constant, although dry seeds breathe less intensively.
FETUS
Fetus- organ of angiosperms; is a flower modified after fertilization. Fruit functions: protection and distribution of seeds. The composition of the fruit includes the pistil and other parts of the flower: the overgrown receptacle, the fused bases of the sepals, petals and stamens. The overgrown walls of the ovary form the pericarp.
Fruit types:
- walnut, nut: dry, indehiscent with one seed, woody pericarp (oak, hazel);
- achene: leathery pericarp, does not grow together with the seed (sunflower);
- weevil: leathery pericarp, fused with the seed (rye, wheat, corn);
- leaflet: dry opening one-celled fruits with many seeds (peony);
- bean: seeds attached to the valves (beans, peas);
- pod- seeds are located on the partition (shepherd's purse, colza);
- box: capsule-shaped, with a lid (poppy, mallow);
- berry: juicy multi-seeded fruit, covered with skin (grapes, tomatoes);
- drupe: juicy, one-seeded fruit, with a three-layer pericarp (plum, cherry);
- compound drupe- a complex multi-stone fruit with a three-layer pericarp (raspberry, strawberry).
Types of fruits and features of their structure
| fruit name | Structural features | Examples |
| Zernovka | The leathery pericarp fuses with the seed | Grains: oats, rice, wheatgrass |
| Achene | The leathery pericarp does not grow together with the seed | Sunflower |
| Nut | woody pericarp | Oak, hazel |
| Lionfish | Achenes and nuts with pterygoid outgrowth | Maple, ash, birch |
| Bean | Fruit, opening with two valves, without septum | Peas, beans |
| Pod and pod | Fruit of two valves with a septum, seeds attached to the septum | Shepherd's purse, cabbage |
| box | Dry fruit opening with a lid or holes | Poppy, henbane, carnation |
| drupes | A fruit with juicy pulp and a lignified inner layer of the pericarp - a stone | Cherry, peach, almond |
| Berry | Multi-seeded fruit with flesh covered with thin skin | Currant, tomato |
| Apple | Seeds lie in membranous dry chambers | Quince, pear, apple tree |
| pumpkin | Seeds lie in the juicy pulp of the fruit, the outer layer of the pericarp is woody | Cucumber, watermelon, zucchini |
| Pomeranian | A multi-celled berry-like fruit, the exocornium of which is brightly colored and contains essential oils. | Orange, lemon, tangerine, grapefruit, lime |
Methods of dispersal of seeds and fruits:
- without the participation of foreign agents (seeds and fruits of large sizes);
- with the help of animals (juicy fruits, berries);
- with the help of the wind (fruits with wings and crests);
- with the help of water (dry fruits and seeds);
- with the help of man (all kinds of fruits and seeds).
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