The escape - The most volatile plant on the appearance of the plant. The main type of green plant escape is an overhead (air) assimilating escape, carrying normal green leaves on the axis. However, the assimilant shoots of unequal. They can be elongated and shortened (sockets), orthotropic and plagiotropic, annual and perennial (skeletal). Often, along with the main function of photosynthesis, these shoots have others: deposition of reserves and support function, vegetative reproduction, formation of flowers and inflorescences. It is very common to change the growth forms of the same escape associated with the change of functions, for example, a socket vegetative escape is replaced by an elongated flag of escape (radishes, cumin) or plagiotropic creeping escape bends up and gives an orthotropic rosette (luggage creeping).
Along with the internal factors regulating the change of different forms of shoots in one plant, there are external factors playing a huge role in the selection of specialized types of shoots in different plants adapting to various types of habitat. Sometimes escape or part of it specialize so deeply that they talk about its metamorphosis; This is most often associated with the full or almost complete loss of photosynthesis function and the acquisition or enhancement of other functions. This especially concerns the shoots living under the ground, ordinary for perennial plants. Under the ground, photosynthesis is impossible, since there is no access of light, and underground shoots act as organs of the permitting of an unfavorable period, stock and renewal bodies. Moreover, during the adaptive evolution, the leaves and stems are usually metamorphic, and sometimes kidneys.
Trunk and bitch trees . In deciduous trees, each one-year escape loses an assimilative function after the first growing season, in evergreens - in a few years. Some of the shoots in the system after the loss of leaves die out entirely, but most of them remain as the main skeletal axes performing a support, conductive and stocking functions for decades. It remains and modified, significantly thickening due to the activities of Cambia, stem parts of the shoots and some amount of kidneys that turn into sleeping.
Kaodex. . Perennial herbs and semi-shops with a well-developed rod root, which remained all his life, forms a kind of perennial part of shooting origin, called cakex. Together with the root, it serves as a place of deposit of spares and bears a lot of renewal kidneys, some of which can be sleeping. CaudEx is usually underground, rarely elevated and formed from the lower parts of shortened overhead escapes submersible in the soil. The border between the stem and the root in adult plants is usually unclear, so the caudax together with the root is sometimes called the stitching. Caudek plants are a lot among legumes (alfalfa, lupins), umbrella (female, furul), composite (dandelion, wormwood).
Rhizome. Rhizome, or rhizome, it is customary to call more or less durable underground escape, horizontal, oblique or vertical in the direction of growth, which performs stock depositing functions, and sometimes vegetative reproduction Perennial plants are usually not in adulthood the main root. Spare substances, mainly starch, are postponed in the axial (stem) part of the root, which is thickened and rich in parenchymal fabrics. Rhizome usually does not carry green leaves, but it has at least a young part, a well-pronounced metairer structure. The nodes are highlighted either by sheet scars and residues of dry leaves, or by alive scaped leaves, as well as the location of the sinus kidneys. According to these signs, rhizome is easy to distinguish from the root. As a rule, pressing roots are formed on the rhizome, located in nodes or in the interstitial ages or groups (urine). From the kidneys of the rhizome, its lateral branches and overhead shoots grow.
Running in the top of the top, the rhizome can gradually die and collapse in the older part. The young part of the rhizomes usually "moves" forward, carrying the renewal kidney into new points, or another distance from the previous above-ground shoots. Depending on the predominance of short or long intercose or on the intensity of increasing the rhizomes, the short and long rhizomes, short-cornese and long-lung plants are distinguished.
In general, the rhizome can be monopodies (worsion eyes) or sympences (boupe). The rhizomes are formed or initially under the ground (Lily of the Lily of the Lily, Blueberry), or first grow as overhead assimilating shoots, which are then immersed in the soil and turn into rhizome (median, hoofer, strawberries).
When the rhizomes are branched, forming several subsidiaries, it is formed by Kutin's overhead shoots, which actually belong to one individual, while they are related to underground "communications" - areas of rhizomic systems. If the binding parts are destroyed, then individual parts of the rhizomic systems are isolated and vegetative reproduction occurs. The combination of new individuals formed from one vegetative way is called clone. Rhizomes are characteristic mainly for grassy perennials, but there are shrubs (bearer), and shrubs (lingonberry, blueberries). The duration of the life of rhizomes ranges from two to three to several decades.
Underground collines and tubers. The short-lived thin underground shoots were called underground chains. The staff does not have an inventory function. Stokes, most often growing horizontally, serve mainly for vegetative reproduction of plants. Top kidneys of Counters often grow up, thicken and turn into tubers (potatoes). The tubers differ from the rhizomes of the shape (spherical, oval), more powerful thickening of the axis and the stronger reduction of the leaves. Tubers do not always develop on the columns. In some perennial plants, the hypocotyl and the basis of the main escape (cyclamen) are smashed and thicken and thicken. In all cases, the tuber is a storage body.
Overhead collines and mustache. Overhead collines are short-lived creeping shoots that serve to capture the territory and vegetative reproduction. If this escape carries green leaves and participates in photosynthesis, it is called the leaf (the belly creeping, the bounds). In the forest I. sad strawberry Overhead collines are higher specialized for the function of vegetative reproduction. They are deprived of developed green leaves, stems of their thin, fragile, with very long interstices. Such aboveground collisions are usually called mustache.
Bulb - It is underground, less often an overhead escape with a very short flatted axis - and scratched fleshy, juicy leaves, sparkling water and soluble nutrients, mainly sugar. From the top and basin kidneys, the bulbs grow overhead shoots, and appendant roots are formed on the bottom. Thus, the bulb is a typical organ of vegetative renewal and reproduction. The bulbs are most characteristic of plants from the family of lily (lilies, tulips, bows) and amarylline (amaryllis, daffodils, hyacinths close to it (Fig. 74).
As an organ of resumption and stock, the bulb is adapted, mainly to the climates of the Mediterranean type - with a soft and warm wet autumn, sufficiently soft winter and with a very hot dry summer. It serves not so much for prosperous overwhelming, how much to experience a tough summer drought. Parentine of water in parenchymal tissues of bulbous scales is ensured due to the production of these tissues of special mucous substances, swelling and firmly holding water. In most cases, bulbous plants behave like ephemeroids, i.e. Their overhead flower shoots live very long, appearing early in the spring, and to the beginning, summer, after fruiting, completely die away, "running out" from drought. Almost an underground bulb remain as a long-term organ for summer and winter. In our country, bulbous plants are most abundant in the steppes, semi-deserts and some deserts, as well as in highlands and broad forest. Many bulbous plants, mainly from South Africa, bred in rooms (crynums, amaryllis, etc.).
Clubnewukovitsa. Externally, these bodies resemble the bulbs, but they have scratched leaves are not puzzling, they are dry, film. Actually, the basic body is the stalking part of the clubnelukovitsa, it is thickened and parenchymalized. Clubneelukovitsa is rather a license tuber, not a bulb. Clubneelukovits are characteristic of plants such as gladiolus, saffron.
Succulent shoots . Juicy, fleshy, adapted for the accumulation of water can be not only underground shoots - bulbs, but also overhead shoots, usually in plants living in conditions of a long lack of moisture. Such plants are called succulents (lat. Succus - juice; succulents - juicy plants). At the same time, the leaves, or stems, sometimes even kidneys can be actually watering organs.
Leafy succulents are very characteristic of the Tolstanka family, for which it got its name (schuchi, Rhodiola, or the Golden root; Moldo, etc.). In addition, leafy succulents, like bulbous plants, are rich in the family of lily and amarylline and close to them (for example, agave) (Aloe, Agava, etc.). These are plants in South Africa desert, Central and South America. Their shoots retain the main function - participate in photosynthesis. But the leaves, except for green mesophyll, have many layers of water-based passage of the parenchyma.
One of the few examples of the kidney metamorphosis into a succulent organ - a Kochan formed in conventional cultural cabbage. Numerous Koch leaves are almost colorless, contain few chloroplasts, meatysters and accumulate a lot of water and soluble spare substances, mainly sugars. The emergence of such specialization is easily explained by the Mediterranean origin of the cabbage. Here, after a warm wet spring, a hot dry summer is coming, which is experiencing such a waterproof kidney (it is natural that in wild ancestral forms, it was not so hypertrophied as cultural varieties).
Sing succulents are most brightly represented and diverse in a purely American family of cactus, as well as characterized for many African Rochane, some lastone and mooring. Usually, a loss or metamorphosis of leaves is associated with the formation of a succulent stem; Juicy stalk performs both functions - both assimilation, and water-free. In most cacti stems column-like or spherical, the leaves are not formed at all or are represented by quickly falling scales; In the nodes there are metamorphic shortened side shoots with bunches of spines or hairs instead of leaves, the so-called "AREOLA". Surprisingly the convergent similarity of the succulent shoots of some African mochadox and American cacti, which can be distinguished only during flowering. On the example of cacti and other stem succulents, it is clearly seen that the metamorphosis affects not just stem or leaves, but the whole escape as a whole.
Spines. Cacti barbs have sheets. They express the reaction of the plant for lack of moisture and the tendency to reduce the evaporating surface of the plant. The secondary biological role of these spines can be in protecting plants from eating their animals, which, of course, contributes to the survival of spiny forms in the process of natural selection. Leaf spines are found in other, non-bankrupt plants (barberries).
In many plants, the spines do not have a sheet, but stewed origin, in the wild apple tree, wild pears, crazy in the spines metamphizes shortened shoots that have limited growth and ending with the edges. The view of the tough weighing spiny they acquire after the leaves of the leaves. A hawthorn barchs that are forming in the sneakers of the leaves and corresponding to the side shoots are absolutely belligerent from the very beginning. In Glootichia, powerful branched spines are formed on stems from sleeping kidney.
The formation of a barrier of any origin, as a rule, is the result of a lack of moisture, permanent or temporary. When growing prickly plants in an artificial wet atmosphere, they lose spines: instead of stem barns, normal fighter shoots grow (for example, in English).
Fillocladium and prettle. The adaptation to the lack of moisture is very often expressed in early loss, metamorphosis, the reduction of leaves losing the main function of photosynthesis. This is compensated by the fact that the role of the assimilant authority takes on the stem. Sometimes such an assimilant stem of a non-free escape remains externally unchanged, but can be metamphized in philloclady or quarters. This is flattened leaf-like stems go whole shoots. The most common example is a needle (ruscus). On the shoots of the needle, in sneakers of scratched leaves, flat sheet filocladium are developing, topographically suitable for a whole stubby run and having limited growth (like a sheet). On Fillocladia, in turn, scratched leaves and inflorescences are formed, which is never happening on normal leaves. The same phenomenon is typical of the types of large tropical genus Fillantus (Phyllanthus) from the family of the Rochetia. Georgic Iligitsa Zamparagus (Asparagus) is characterized by small, sometimes needle filoclades, sitting in the sneakers of the scratched leaf leaves of the main skeletal escape.
Flared green stems with rather rigid consistency are functionally replaced by the leaves, in general, help reduce evaporating surface. At the same time, as in other cases, it is metamphized not leaves or stems separately, but the whole escape, most often their system.
Layers, unlike philocladium, are called flattened stems that retain the ability to long-term growth. They meet, for example, the Australian Mulenbeck (Muhlenbeckia Platyclada) and the Colletia Mexican shrub.
Mustache. For many liable plants, the modifications of leaves or their parts are characterized, and sometimes whole shoots in the mustache, which have the ability to spin around the support (other plants, hedges, stones and other solid items). The stem is usually thin and weak, unable to retain the vertical position.
Many legumes with peristoid leaves in the mustache turns the upper part of the sheet (central vein and several leaves, for example, in peas, peas). In some types of ranks (Lathyrus), for example, by L. Aphaca, the entire sheet plate is turned into a branched mustache, and the photosynthetic function takes on large green strips. In other cases, strips are transformed into the mustache while maintaining a normal sheet plate (Sassaparil - Srnilax Excelsa). Excellence mustache can observe different species Grapes, passiflora and a number of other plants.
Metamorphosis -modifying the replacement of the shape and function change.
Spinysplants of hot dry habitats can be both storm and sheets. They perform two functions: reduce evaporating surface and protect with animals damage. Sticks of stem origin are developing at the top of the stem, in the sinuses of the leaves or are located on the stem node oppositely (hawthorn, pear, turn). If the parts of the sheet participate in the formation of the spin, then spiny teeth (thistle) are formed. Frequently, strips (White Acacia) or the entire sheet (Cactus, Barbaris) are modified in the barrier.
Fillocladium- Greek. phillon- leaf; klados.- The branch is a modified lateral shoots that take the form of a sheet plate and performing a photo seating function (a needle), in general, contribute to the decrease in the transparency surface. On the shoots of the needle, in the sneakers of scratched leaf leaves, leaf-shaped philoclands are developing, topographically suitable for a whole stubborn run and having limited growth. Shetoid filoclades are also characteristic of the types of tropical Fillantus. For asparagus, small sometimes needle filoclands sitting in the skeletal skeletal escape leaves are characterized in sinuses.
Tubers- It is a strong thickened fleshy underground or overhead shoots. The underground tubers leaves are reduced to small, early leaving scales, in the sinuses of which are kidneys, called eye (potato tubers). On the kidneys develop shoots. Overhead tubers are formed due to the strong growing of the stem and carry normal leaves (Kohlrab cabbage).
Bulbs -modified shortened underground (less often overhead) shoots. Underground bulbs - on Luke of the Republic, garlic, wild onions. The lower part of the bulb, its dense base, is a shortened modified stem, which is called the Don. Donets has a flat or cone shape. In its lower part, a large number is formed podep rootsAnd upward leaves (fleshy scales), sparkling water and nutrients are directed from it. External dry or film scales are modified leaves that perform a protective role, protect the fleshy leaves from drying out.
Rhizome- Underground modified escape, serving for vegetative reproduction and for product stock. Ends up rhizome kidney, not a root case. On the rhizas, the nodes are often noticeable, on which scales are formed - reduced leaves. In the sneakers of the scales there are kidneys, giving rise to the above-ground and underground shoots, and pressing roots are formed from the nodes.
Clubnellukovitsy -these are modified, shortened, thickened like a chalk trees, having a view of a bulb (gladiolus, crocus). In contrast to the bulbs in the clubnevice there are no juicy flakes, so nutrients are concentrated in the stem part. Roots are developing on the bottom thickened part - the dona, and in the upper part there is a central kidney, from which the flowers are formed with leaves. Something of the tuberukovica is covered with dry films - leaves, in the sinuses of which kidneys are located.
Mustache - Creeping stems with long interstices (strawberries, bounds). For many liable plants, the modifications of leaves or parts are characterized, and sometimes whole shoots in the mustache, which have the ability to spin around the support in the process of long-term top growth. The stem is usually thin and weak, unable to retain the vertical position. Many legumes with peristoid leaves in the mustache modifies the upper part of the sheet (Rahis and several leaves). Very characteristic alert of sheet origin are formed in pumpkin . A mustache of shooting origin can be observed in different types of grapes (wild and cultural, in passiflora and a number of other plants).
Life forms of plants
Life form, or biomorp - B.the small appearance of plants, which occurs in ontogenesis as a result of growing in certain environmental conditions and is adaptive.
Trees.they have a well-pronounced overhentable main trunk, growing vertically more intense other shoots and the plants remaining throughout the life of several dozen to several hundred and even thousands of years.
Shrub - The main barrel is absent or poorly expressed, the branching begins almost at the very earth itself, therefore several more or less thin stems are formed. As you die in the center of the bush of the main stem and the nearest subsidiaries appear new ones on the periphery. The duration of the life of the shrub reaches several hundred years, but each stem lives 10-40 years old (yellow acacia, lilac - up to 60 years old). The height of the shrubs does not exceed 4-6 m (barberries, caticker, Irga, rosehip, currants).
Shrubcharacterized by the same method of branching as shrubs, but they are more shorter and have a smaller life expectancy of skeletal axes - 5-10 years. Blueberry, Lingonberry, Blueberry, Cranberry, Heather, Khwoman.
Polukstarniki and semi-shopthey have shoots that in the lower part remain perennial and plug, and in the upper part - annual and in winter die or dry out. The life expectancy of their skeletal axes is 5 - 8 years old. They are characteristic of desert and semi-desert areas (wormwood, saltwood).
Herbate plantscharacterized by the fact that the stalks are not delayed and overhead parts are usually die away by the end of the growing season. Herbs are annual, twilight and perennial.
Plants pillows- squat forms in the form of dense pillows. Shoots carrying leaves, perennial; Soothes, bearing flowers, die away by winter. Pillies plants are characterized by the increase in the growth of all shoots. They are confined to the most unfavorable habitats with low temperatures Air and soil, with cold winds (tundra, highlands, deserts, rocks, screaming), where free access of light suppresses the growth of shoots.
Succulents- Forms having juicy leaves and stems that contain plenty of water (Coiding, Moldova).
Liana- Forms having a long stem (rustic or grassy), which in hold in a vertical position needs a support (hops, binds, lemongrass, grapes).
Types of bunching Zlatkov
Depending on the length of the underground part of the shoots and the directions of their growth distinguish between cornerstic, tightly - bush and rylocker cereals.
1. U. rhizablepodlatsy Vlagovy Slavs form underground long branching rhizomes, from which desalted above-ground shoots are departed, usually removed from each other (creeping powder ). Long - cornese, or sibling gravestive long rhizomes. This feature of long-lung cereals is used when attaching sands (types of colosnia). Shortocornias cereals, or bushes with short difficult-distant rhizomes (meadow, fragrant spikelers, hedgehog team, Timofeevka meadow, etc.). The kidney of the resumption of rhizable plants is laid with the preceding autumn and, as a rule, winter in the soil at different depths, and early in the spring of these plants appear above-ground shoots.
2. U. rykhlokokustov The cerealpodeside part of the invulsive shoots are short, from 2 to 10 cm, the ends of the shoots, bending to the surface of the soil, turn into overhead shoots, forming a loose turf. Ruffer Dernovina is a parent plant with apart from him at some distance side barren shoots (Timofeevka meadow ).
3. U. tight - bush ZlakovVTRIVENIVE RESUME, Therefore, a dense turf is formed, the side shoots grow vertically and tightly pressed to the stalk of the mother plant (fading) .
Sheet
Sheet- lateral organ of restricted growth, increasing its base. Functions of leaves:
1. Photosynthesis and transpiration;
2. gas exchange;
3. stocking;
The main parts of the sheet:
L. hasic record -the main part of the sheet is the main organ of photosynthesis.
Cherchok It serves to attach sheet to the stalk and for the best location of the leaves in relation to the light, contributes to the weakening of the shocks on the leaf plate of rain drops, hail, wind. Participates in the movement of leaves.
Vagina - The extended lower part of the sheet, which more or less covers the stem, protects the stubble kidneys and increases the strength of the stem when flexing (in cereals, of some umbrella).
Highlights - Paired lateral growths at the base of the sheet of different shapes . They protect a young leaf in the kidney.
Cheerful leaves With a camp.
Sitting leaves- In the absence of a stuff.
Simple leaveshave one sheet plate, solid or sometimes strongly dissected.
Complex leavesconsist of several sheet plates (leaflets), which are attached to Rakhisu (the total axis of the complex sheet) with their own sweets.
BUT- Simple sheet of apple tree: 1 - sheet plate; 2 - puffs; 3 - Highlights; B.- Sophisticated rowan sheet
Flower
Flower -shortened and limited to escape; The generative body of sexual reproduction.
Flower structure:
A, B.- Flower structure schemes: 1 - a color; 2- chashelistic;
3 -paste; 4 - stamens; 5 - Pestik
Bract -caring, in the sinuses of which flower is located.
Flooring -partstec under flower.
Coloros -part of the stem, carrier of inflorescence.
Sedentarythe flower does not have flowers (flowers in the heads of some clovers, in the baskets of aster).
Receptacle- The upper extended part of the flowerwalk serves to attach all the other parts of the flower.
Cup It consists of green free or accredited cupid.
Venchikcomplicated from free or threw painted in different colours Petals. Cup and winky supplies perianth, or cover, flower. The perianth protects the actual flower (stamens and pestles) from external adverse effects and attracts insect pollinators.
Simple perianth It is formed only by a cup (extinity, nettle, sorrel, male oak flowers, elm) or only a wedge (tulip, lily, valley, prolesta).
Double perianth Consists of a cup and a bunny (apple tree, gravel, pots, lilac).
Constracial (naked) flowers (Iva, ash, poplar) do not have a perianth.
Stamenit consists of a stitching thread and anther, rarely formed seating anthers without a stitching thread (magnolia) or anthers are underdeveloped. In anthers, pollen is formed, serving for pollination.
Pestleit is formed as a result of the capture of one or several rests. Each pestle is allocated marking, columns and a stall.
Ovary- This is the lower extended part of the pestle. Stigmapestley is adapted for pollen to capture and retain. Inside the wounds are formed summer(seeds).
Natrices -special glands excreasing Sakharist liquid - nectar.
Bloom - Opening the anthers and the functioning of the fishing of pestles.
Pollination -the transfer of pollen from the anthers of the stamens on the pistol stilts.
For self-population Pollen is transferred to the pistil stil within this flower or this individual. Self-pollination is considered as a phenomenon caused by unfavorable conditions of the medium, i.e. unfavorable to cross pollination; It fulfills the assurance role. Self-polling happens more often with brief life cycle, growing in unfavorable environmental conditions on dry and poor soils (shepherd bag, clover rough, clover is boring). This type of pollination allows them to restore the number of species.
Cross pollination - the main type of pollination of flowering plants. It is biologically more completely.
Biotic pollination:
Entomophily - pollination with insects. Insects attend flowers for collecting pollen, nectar, and sometimes in search of asylum, egg deposition, search partner. Flowers attract insects with their aroma. Aroma. essential oil Not always pleasant. The smell of rotting meat is publishing rafflesey flowers, stock, some kirkazones. Such a fragrance attracts flies as a place to deploy eggs.
Ornithophilia- pollination of birds is a phenomenon characteristic of the tropics. Birds (Hummingbirds, Naks, Flower) are pollinated by Eucalyptus, Cannes, Aloe, Acacia, some cacti, fuchsia. Flowers of these plants are odorless, but have a bright color, highlighting a lot of watery nectar.
Chipterophilia- pollination battle miceDistributed in the tropics of Asia and America. They are pollinated by such plants like banana, agawa, baobab. Flowers have greenish yellow, brown or purple color, which is better perceived by bats at night. In addition, these flowers have durable "landing platforms" - thick spacing, durable lateral sections of the branches, a sharp smell that simulates the smell of the volatile mice themselves.
Abiotic pollination:
Anemophilia- pollination with the help of wind. Winding plants bloom to the dissolution of the leaves (flashes, birch), their flowers without perisheries, odorless and coloring of petals (unspoken), but with large cereal stigs. Flowers are collected in inflorescences (earrings, brush, colosum). Stamens freely hanging.
Hydrophilia - transfer pollen with water or water surface. This pollination is characteristic of a few. water plants (Valisneria, Elodea, etc.). In Wallinia, pollination occurs on the surface of the water. A polished female flower then leaves again under the water.
Fertilization -this is the merger of two genital cells - Games (male and female), as a result of which a new cell is formed - the zygote from which the germ of the new organism develops.
Seed. Fetus
Fetus - This is an organ that develops after fertilization from Zagazi. Protects seeds and promotes their distribution.
After the process of fertilization of the seed (seed dip) turns into a seed.
Bean seed:
but -general form; b. -Relid; 1 -core; 2 - Sexod; 3 -bube; 4 - seed seam; 5 - kids; 6 - stalk; 7 - Semiyland
Seed- the reproduction body of all seed plants.
Peelseed is a modified chip cover. It protects seeds from drying, premature germination, possible mechanical damage.
Germsemen, as a rule, develops from a fertilized egg . The embryo consists of the root, converted to the seumavor, the ridiculous stem (sampled knee, or hypocotyl), cotyledons - the first leaves of the embryo and kids. Honeycomb consists of a cone of the rise and incar of the leaves.
Endosperm -fabric, basin nutrients necessary for the development of the embryo.
Taking acceleration of seed germination
1. Washing seeds in water at a temperature of 25 ... 30 0 s for 24 ... 48 hours, depending on the density of seed shells. They germinate in plates on garle, cotton, napkin, sticking water just above the level of seeds. Capacities with seeds are covered with film or glass. The swollen seeds are slightly dried and immediately sowed.
2. Stratification - Exposure of seeds for some time at low temperatures (0 ... 5 0 s) in a wet substrate (sand, peat, moss). In the fall, the seeds are mixed with sand 1: 3, the mixture is poured into the boxes. Stored at a temperature of +5 0 S. In the spring, the seeds are separated from the sand before sowing the seeds.
3. Scarification- Mechanical damage to the fat and rigid shells of seeds.
4. Seed treatment hot water 80 ... 85 0 С for 24 hours
5. Waste seeds in solutions chemical substances. Conducted to softening solid seed covers or growth stimulation.
Plant growth and development
Height- This is the process of neoplasm elements of the structure of the body, which is accompanied by an increase in mass and sizes.
Development -these are high-quality changes in the structure and functional activity of the plant and its parts in the development process.
Growth phases:
1. Embryonic phase -growth is carried out by dividing meristenity cells. Requires high costs nutrients and energy.
2. Phase stretching -cells are increased in size, they appear vacuoles, which are later merged into one large.
3. Phase Differentiation - The final formation of the cell is occurring, turning it into a specialized cell (conductive, mechanical, etc.) with the dominance of the respective structures or organelles.
4. Stationary phase- The number of cells and their biomass changes weakly.
5. Phase degradation- Cell death.
Ontogenesis – individual development The body since the formation of the zygote to death.
Stages of plant development
1. The embryonic period in seed plants lasts from the moment of formation of the embryo (seed) before the start of seed germination. In vegetatively breeding plants - from the moment of the formation of kidneys in the organs of vegetative reproduction and before their germination. Growth processes are in the hidden phase.
2. The juvenile period of the investment of the growth and development of vegetative bodies from the germination of seed or vegetative kidney to the emergence of the ability to form reproductive bodies. Plants increase in size, the growth processes prevail.
3. Maturity - a period from the appearance of the first primordants of reproductive organs before the formation of buds, bulbs. Growth processes are combined with the formation of flowers, vegetative organs of plants continue to grow.
4. Reproduction - fruiting, development of the fetus, seeds, tubers. The processes of formation of flowers, seeds, tubers, bulbs prevail.
5. Old age - from complete cessation of fruiting to natural die away. Growing rare (stitching pigs, gouring shoots).
Metamorphoses are hereditaryly fixed modifications of organs related to the change of their basic functions. Metamorphosis of vegetative plants organs is extremely varied.
Metamorphosis root
One of the most interesting phenomena in the root biology is its mutually beneficial cohabitation with mushrooms. Is this a phenomenon of a special name? Mikoriza (which literally means fungocorn) and extensive literature is devoted to him. Mycorridge is characteristic of the overwhelming majority of flower plants (probably at least 90%). By virtue of such a wide spread of mycornis, it is rather a rule than the exception, but following the established tradition, we consider it still as a radiation of the root.
On the other hand, many plants, such as orchid, especially leading saprophistic lifestyles, are so closely associated with mushrooms that they cannot even develop without a "infection" with a specific mycorrhisan mushroom.
Mikoriza is two different types.
To the first type applies ektomicoriza (Outdoor Mikoriza). In this case, the gifs of the fungus will increasing the roots of the plant with a thick case (gifovy mantia) and penetrate, in addition, in interclausers (but not cell cages). Under the influence of hormones secreted by the mushroom, young roots are abundantly branched and the endings are thicken. Extracticorosis is characteristic of many temperate trees, including oak, birch, Yves, maples, coniferous rocks, Poplar and others. Extracticizes form almost exclusively basidiomycetes, less often ascomycetes.
Wider, almost universal distribution has endomicoriza (Inner Mikoriza). It can be observed, for example, apple tree, pears, strawberries, tomatoes, cereals, orchid and many other species. It is characteristic of most flowering plants. With endomicorism, the fungal case around the root is not formed, root hairs do not die, but the gifs penetrate much deeper in the root fabric and are introduced into the cord parenchyma cells. There are several different types Endomicrises, with some of them very different from each other.
The most specialized type of endomycorrzees can be observed in orchid. Orchid does not have a hymical mantle around the roots and myceliums is almost entirely inside the root. Gifs of the fungus in ceres of cortex form peculiar balls. These tangles are subsequently digested by the host plant. Mushrooms forming organic orchid mikuriza are able to decompose complex organic matter and supply roots with products of their decomposition. And this is of particular importance, with a saprophite power method. The mushroom component of endomicrod of this type is almost always represented by oomycetes.
The great importance of mycorrise has in tropical rainforests. Due to the strong washing regime (daily fallout), these forests are practically deprived of the soil (all nutrients from the soil are washed out). Before plants, the problem of nutrition is sharp. At the same time, fresh organics are a lot: fallen branches, leaves, fruits, seeds. But this organic is not available to higher plants, and they come into close contact with saprotrophic mushrooms. Thus, the main source of mineral substances under these conditions is not soil, but soil mushrooms. Minerals come to the root directly from the GIF mikoriznaya mushroomsThat is why the surface root system is characteristic of the rain forest plants. How effectively mycariza works, it can be judged at least for the fact that the tropical rain forests are the most productive communities on earth, the maximum possible biomass is developing here.
The cohabitation of roots of plants with nitrogen fixing bacteria is significantly less. True, the biological significance of this phenomenon is extremely high. In addition to all the well-known legumes, the root fools are marked with representatives of other families, for example, in some conifers, in a row, in a number of casuarine, crash, loches. Dwell on this wide famous phenomenon we will not.
Usually in the roots of any plants, a certain amount of spare nutrients is postponed, mainly carbohydrates: especially starch and sugar; Other species? Inulin. But in some cases the reserves function is hypertrophied and performs to the fore. At the same time the roots thicken, become meaty. Most often occurs the structure having the name rootpode. It is especially characteristic of two-year plants: beets, radish, trouser, tour, carrots, celery and many others. From the exotes you can call the stain sin, chicory. Roots have a complex morphological nature, because the root and stem in the formation of the root (more precisely, the satellite knee - hypocotyl) takes part. But in order to establish: which part of the root is represented by the root, and what stem? Special anatomical studies are needed.
Thickening in the form of root cones are found in plants with a basic root system, for example, by Georgin.
In many cases, the roots are adapted for vegetative reproduction. In a number of perennial plants from root appling kidneys, overhead shoots are developing. These shoots are called root offspring. Corneeotryst plants include: aspen, plum, cherry, lilac, bind, Badan, Osay. The latter are malicious and difficult to eradicate weeds. Small pieces of horses are cut in the soil processing easily and give rise to new plants.
In many lumping plants, for example, ivy, there are special apparent roots on the stem, penetrating the cracks and irregularities of the tree, rocks, or walls and firmly retaining plants.
There are even roots-hooks, like a crunch ficus.
A completely different function carry so-called contractile (shortening) or retracting roots. They are characteristic of many corpsy, bulbous and tuberukovic plants. A classic example of a plant with precipitated roots is crocus. The crocus, besides ordinary roots, develop longer contractile roots, which, with a reduction, pull the tuberukovitsa to the ground. At the same time, the contractile roots seem to fall out, become cross-wrinkled and on this basis are easily different from ordinary roots.
In special cases, the roots may be tanks for water supply. Many tropical epiphytic orchids (and epiphytes are plants that are used as a substrate for growing other plants) outdoor The crust, which is called Velen consists of empty large cells that can absorb water like a sponge. During the showers, these cells are filled with water, which is stored in them and as needed by the plant. By origin, Velamen is a multi-layer risodeterm.
Many tropical wood plants, mainly mangrove (for example, aviation) growing on freshwater tropical swamps, as well as in shallow water of oceanic coasts, are developing special ventilation or respiratory roots? Pneumatophores. They appear on underground side roots and grow vertically up, lifting over water or soil. It is noteworthy that negative geotropism is characterized for such roots.
The same mangrove plants form the roots of another type, which are called wetting. These are apparent roots - backups. They appear on the trunks and branches and grow down, they are embedded in the substrate and firmly hold the plant, for example, in soft ile. Such roots have a widespread plant of mangrove thickets - rizophora. But the most spectacular wandering roots at the Banyan Fikus ( Ficus Benghalensis). Numerous apparent roots of Banyan grow down, rooted and develop their own root system. Thanks to this, the Banyan tree grows into a whole grove. Such groves can occupy impressive areas.
No less interesting supporting wildflower roots, characteristic of large trees of tropical rain forest. For known reasons, rainforest trees have a surface root system, at the same time, the trunks of the trees of the first tier reach huge sizes. The roots of the usual structure can not whine a plant in the soil (which is also not), holding these giants during frequent storms and shower. Therefore, at the surface of the soil of the roots of such trees, special vertical grows are developing, like boards adjacent to the tree trunk.
First, the shell roots are rounded in cross section, but then a strong one-sided secondary growth occurs. In a tropical rainforest, the height of the shell roots often exceeds human growth.
No less peculiar root roots of our ordinary marsh plants - they have a "storey" structure. True, these roots do not have a special name.
Metamorphosis escape
Escape is the most volatile organ of the plant. It is characterized by such properties as:
- multifunctionality;
- behavior lability;
- plastic.
Already in the first approximation, the shoots are divided into two types: 1) vegetative and 2) generative.
There is a distinct change of the forms of growth and escape functions in the process of its biological development. For example:
- capture of a new area (whip or rhizome);
- enhanced nutrition (foster stage);
- formation of colors and fruits (generative stage).
Consider the main types of specialized and metamorphic fiction bodies.
Kaodex.
Develops in perennial herbs and shrubs with a well-developed rod root. Is it a kind of perennial organ of shooting origin? Usually weighing the lower sections of the shoots, turning into a rustic rod root.
CaudEx carries numerous renewal kidney. In addition, CaudEx usually serves as the place of deposits of spare nutrients.
As a rule, CaudEx is underground and rare enough? Overhead.
The shooting origin of the caudex can be installed on the sheet scars and the logical arrangement of the kidneys. From the rhizomes of cakex is distinguished by the method of dying. The gradual die away comes from the center to the periphery, while the organ is divided (cracks) longitudinally into separate sections - partitions. Accordingly, the membering process is called partitioning. As a result, a structure is formed, which is often called: a multi-core rhizome, styling rhizome, a multi-rod stem rod, a stitching. These names definitely reflect the appearance of the Cacex, create its image.
It should be noted that particulation is characteristic of old (syntile) plants.
Caudex is especially pronounced in semi-desert, desert and high-mountain plants. Some types of caudaceses achieve a huge size and weight, for example, among representatives of Panganos to 15 kg.
In systematic relations, couquet plants are a lot among legumes (alfalfa), umbrella (hip), complex (dandelion, wormwood).
Rhizome
Rhizome or rize (root-like)? This is a durable underground escape that performs the functions of vegetative renewal, reproduction and often depositing stocks. The rhizome usually does not carry green leaves, but it has a clear metaalog structure and it differs significantly from the root. The nodes are highlighted on sheet flakes, scars or sinus kidney.
As a rule, abundant apparent roots, located in nodes with urine or one, are formed on the rhizome.
A fatty as a distal part, rhizome gradually dies in the old one? proximal part.
Depending on the degree of development of interstitial rhizomes of the plant divide on:
- long-level;
- short-corneous;
- potted.
When rhizome is branched, it is formed by Kutin's overhead shoots, which actually belong to one individual. Such curtains are called clone.
So for many plants, a clonal form of growth is characteristic. There are two ways to form rhizomes.
Some plants initially all the escape above ground. It carries and scratched and green socket leaves. In the future, the leaves die away, and the stalking part is drawn into the soil, it is thickened due to the deposition of spares and turns into rhizome.
Thus, in the structure of escape you can distinguish between the two phases: overhead and underground. During ontogenesis, escape undergoes the actual transformation, metamorphosis literally. Such rhizomes are called submersible or epigeogenic - elevated. Such a picture is observed in the formation of rhizomes: cuffs, gravity, strawberries, medics and others.
In other plants, the rhizome begins the growth phase from the kidney underground. Such rhizomes of initially underground origin are called hypogogenic. Very many many years of herbs and shrubs are observed: Drubwear, Voroniye Eyes, Pourery, Veronica Long-Colutive and others.
In this case, the root of the thin and serve as more for vegetative reproduction.
Underground collines and tubers
Tubers Thickening underground escape like potatoes, Topinambur. Are fatty thickens begin to develop at the ends of underground stems? Strokes. Stokers are short-lived and usually destroyed during the growing season, they differ from the rhizomes.
In the tubers are predominantly parenchymal core cells. Conductive fabrics are very weak and noticeable on the border of the core and bark. Outside, the tuber is covered with a periderm with a thick layer of cork, helping to carry a long winter peace.
The leaves on the club fall very early, but they leave the scars, in the form of the so-called tuber's eyes. In each eye, there are 2-3 stubborn kidneys, of which only one germinates. Kidneys for favorable conditions Easily germinate, feeding the spares of the tuber and grow into an independent plant.
Thus, the third leading function of underground shoots? Vegetative renewal and reproduction.
Some species of plants form very peculiar leafy tubers (for example, a thin colostal core). These are modified leafy plates sitting on rhizomes stuffing. These leafy tubers have blades, cigarette residence and even mesophilma fabric, but are barefilly and are adapted to postpone the spare starch.
Clubneelukovitsa and Lukovitsy
Gladiolus clubdelukovitsa like appearance on the bulb. However, on the longitudinal cut, it can be seen that its stem is strongly developed and turned into a tuber containing spare substances. The bottom of the tuberukovitsa arise numerous appendage roots that form the urine system. Among them are both contractile (retractable) roots.
The bulb represents another kind of strongly shortened underground escape. In contrast, she has a relatively small stroke part? Dame. Numerous juicy leaves are attached to the Don and the names of bulbous scales are attached.
In a garden onion, for example, fleshy scales are covered with protective film-free dry scales, therefore the entire bulb of this type is called a film tunication or concentric. In lilies, the fleshy scales are tile, respectively, and the bulb is called tile.
Juicy scales of bulbs are only lower escape leaves. The upper green leaves are in the top of the Donets.
All bulbs are combined in two categories: with rhizomes and without rhizomes. The bulbs with rhizomes have the ability to multiply by folds: the rhizomes are growing from the dandy of the bulbs, which are lengthened horizontally in the soil and at some distance from the maternal bulb form a new bulb - folding. The bulb is rooted and after a few years it can bloom. This category includes some tulips and wild onions.
Bulbs without rhizomy are familiar to everyone because they serve as ordinary planting material in vegetable growing and flower growing.
In the sinuses of juicy leaves, child bulbs (kids or teeth) are laid, which are developing before flowering. Many bulukes develop, for example, garlic.
Water supply in parenchymal cells of juicy scales is ensured due to the development of special mucous membranes, strongly swelling in water and retaining water.
In most cases, bulbies behave like ephemeroids. Their overhead shoots exist very short time: they appear early in the spring and die already at the beginning of summer. Plants as if "run away from drought."
Succulents
Succulents call plants having juicy, fleshy leaves or stems, which serve as peculiar tanks for moisture pan. This moisture is very careful and economically spent throughout the arid period.
Succulents are divided into two large groups:
Stem succulents
Strong succulents - have fleshy stems, the leaves, as a rule, turned into spines (to reduce transpiration). As examples of stem succulents, you can call all the well-known American cacti and very similar African Mokhodi.
Leafy succulents
Leafy succulents - have thick, fleshy leaves. These include Tolstanka (Crassulaceae): Clamp, Golden Root; Lily, Amarillic, Agava, Aloe, Gasterei, Gavortia.
Other escape metamorphoses
A special interesting case of kidney metamorphosis in a succulent organ - Kochan is observed in conventional cultural cabbage. As you know, cabbage is a two-year-old plant. In the first year, the sockets appear, slightly succulent leaves, then the kidney increases sharply in size and turns into a kochan. For the second year after falling cabbage, as a typical twiser, gives an elongated color-based escape.
The plants have a wide variety of spikes and barns, which, moreover, have a different origin. For example, in cacti and barberries spines are modified leaves. Usually such spines are intended primarily to reduce transpiration, the protective function in most cases is secondary.
Other plants (hawthorn, wild apple tree) have spiky of shooting origin - These are modified shortened shoots. Often they begin to develop as normal fighter shoots, and then decorate and lose the leaves.
A further step in the underdevelopment of leaves and the transmission of their functions with green stems leads to the formation of such metamorphic organs as Fillocladium and Pondodia.
Fillocladium
Fillocladium (Greek. Phillon - leaf, kestros - branch) - these are flat sheet-like stems and even escapes. The most elegant example of plants with metamorphosis of this kind are the needlers (Ruscus). These plants grow in Crimea and in the Caucasus; Often they are bred and in room conditions. It is very interesting that the needle-shaped needlets and inflorescences, which never happens on normal leaves. In addition, Fillocladiums like the leaves have limited growth.
Layout
Builtries are called flattened stems, which, unlike philocladium, retained the ability to long-term growth. This is quite rare modifications and meet, for example, from Australian Mulenbeki.
In many lubing plants (Peas, ranks, pumpkins, etc.) there is a modification of leaves in the mustache, which have the ability to spin around the support. The stem of such plants is usually thin and weak, unable to save a vertical position.
Sling plants (Strawberries, Kostyolnik, etc.) form a special type of shoots serving for vegetative reproduction, such as the screens and collines. They are referred to as elevated-creeping plants.
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Rhizomes have a sympathous or monopodial branch, like overhead shoots. During the branching of the rhizomes, subsidiary rhizomes are formed, which leads to the formation of Kurtin's elevated shoots. If individual parts of the rhizomes are destroyed, the curtains are separated, which is observed with vegetative reproduction. The combination of new individuals formed from one vegetative way is called a clone. The formation of rhizomes is characterized by perennial herbaceous plants (many representatives of the families of cereals and dies), but sometimes occasionally found in shrubs (bearing) and some shrubs (lingonberry, blueberry).
Overhead escape metamorphoses include overhead collines ╫ ╫ ╫ ╫ ╫ Some plants have young shoots begin to grow horizontally over the surface of the soil as the screens. After some time, the top kidney of such a shoot is bent up and gives a socket that is then rooted. At the same time, the screens are destroyed, and the subsidiaries begin to be independent existence. The function of the weapon is to seize the area and the resettlement of new individuals, i.e. They perform the function of vegetative reproduction. Pleets ╫ These are overhead collines having green leaves and participating in the process of photosynthesis. They are found in many plants (Kostyannik, Zelenchuk, Labor, etc.). Some plants (strawberries, partially bounds) do not have green leaves, stems are thin with long interstices. They got the name of the mustache. The top kidneys of the mustache are rooted, after which the mustache is usually destroyed.
Other metamorphoses of overhead shoots include spines of sheets (cactus, barbaris) and stem (wild apple tree, wild pear, hawthorn, etc.) of origin. The formation of barbles is associated with the adaptation of plants to the lack of moisture. In addition, some plants of dry habitats are conclusted, forming the so-called phillocladium (for example, the needle) and quarters (for example, a college). On the shoots of the needle, in the sneakers of the scratched leaves are formed flat sheet filoclades, corresponding to a whole stubborn run and having limited growth. Quantity, unlike philocladium, ╫ are flattened stems with a long-term growth. Soothes, and sometimes leaves, can turn into the mustache, which in the process of long-term top growth are able to spin around the support.
SHEET
Sheet ╫ is a sidebar of escape, usually a flat form with limited growth and performing photosynthesis, breathing (gas exchange) and evaporation of water (transpiration). Sometimes water accumulates in the sheet and spare nutrients are deposited. It can play a reference and protective function, to be an organ of vegetative reproduction, perform the role of animal traps in carnivorous plants, etc.
The leaves in the flowering plants are formed from the meristem of the cone increasing escape. The rigging of the leaves occurs at some distance from the tip of the escape, forming on the surface of the protrusions in the form of tubercles and rollers. As they grove, they acquire a flat shape and cultivative (that is, with pronounced spinal and abdominal sides) the structure, in contrast to more or less cylindrical and radial-symmetric axial organs ╫ stem and root.
The top and lower sides of the sheet differ sharply under the conditions in which they are (especially in relation to the light regime), and as a result of this, ╫ on the anatomical structure, the structure of conductive beams, downsion and other features associated with the functional differences of the parties. The top side of the sheet is called the inner (or abdominal), the lower ╫ ╫ outer (or the dorsal).
The leaves have limited growth, since the cells insert measurement, due to which the sheet grows, quickly lose the ability to divide. Having achieved certain sizes, the sheet until the end of the life remains unchanged.
The leaves are located on the stem in a certain order reflecting the symmetry in the escape structure. Three types of leaf placement are distinguished: the next (spiral), opposite and mutter. With the next list, the leaves are placed on the stem on the spiral, and one sheet leaves each stem node. The location of the leaves on each node is pairwise, one against the other, is called the opposite, three sheets and more ╫ mutual. Typically, the leaves are placed on the plant so as to ensure the smallest mutual shadens. This phenomenon received the name of the sheet mosaic.
List morphology. The typical sheet consists of a sheet plate, a petiole, bases and horses. If the base of the sheet is expanding, covering the stem, the vagina is formed, in the formation of which can take part and pets. The sheet connected to the stem of the stuff is called cherry, and the base plate connected to it is sedent. In vaginal leaves, the base covers the above-sufficient intercourse in whole or in part, on a larger or less. In "Some species of plants (representatives of the families of legumes, rose colored, etc.) at the base of the sheet there are paired lateral growths ╫ Hightails protecting it in the early stages of development. Dimensions and form of attachments are different. They can exist through the entire life of the sheet or fall after Deploying sheet on escape.
Forms of a sheet plate are diverse. They are determined by the ratio of its length and width and position of the widest part. The plates are rounded, oval, oblong, ovoid, inversely, wide, broad-shaped, reverse, wide, linear. In the outline, form, consistency release leaves of scaly, needle, bristy, sword-shaped, braid, thyroid, and others. In the morphological description of the leaves, the peculiarities of the base, the tops and edges of the plate are taken into account. The base of the sheet can be a wedge-shaped, rounded, heart-shaped, non-uniform, cut, narrowed, sweat and speck-shaped. The top of the sheet is stupid, sharp, pointed, pointed, laid. The edge of the sheet has cutouts of different depths. If they do not enter the deeper 1/4 of the width of the semi-plastic, the sheet is called solid, and the edge of it is rugged. The edge can be a wavy, laid, gallant, gear, palpal, dual, and other leaves, which are cut-offs of the edges of a deeper 1/4 of the semi-plastic, are called dismembered. The dismemberment can be treasured, palpat and pile. If cutouts are not deeper than 1/2 width of the semi-plastic, the leaves are considered blade, if 1/2 of the width of the semi-plastic, but do not reach the medium vein, ╫ separately; If they reach the middle vein or the base of the plate ╫ dissected.
The protruding parts in the bladed leaves are called blades, in separate ╫ shares, in the dissected by ╫ segments. Peristoral leaves with narrow parallel segments are called grains; Leaves peristoid or peristrastic, with triangular shares or segments that have an extended base, ╫ in the strings, peristoid, with large ultimate stakes and smaller side shares ╫ library.
Leaves are simple and complex. A simple sheet has a stiff and one plate and disappears entirely. If the sheet consists of several sheet plates, each of which has a small stiff (called a cutter), it is considered complex. In a complex sheet, leaf plates usually fall independently from another. The leaves can be tricious, and finishing and peristoids. If the common petiole is branched, multi-stroke leaves are formed: twiceperistributing, three pieces, etc.
In the leaf plate there is a strongly branched system of conductive beams, called residents; The combination of them determines the housing of the sheet. The housing is open and closed. With the opening of the alkali, the alkali ends next to the edges of the sheet plate, without connecting each other. By the nature of the branching of residents, such a housing is called dichotomous or fan. With the housing of the alkali, the alkali is repeatedly connected to each other and form a network ╫ Mesh housing. Mesh jiluations are called a pile, when side, more subtle, multiply branched veins depart from the average vein to the parties. With a palpal of housing, at the base of the sheet plate, more or less identical veins are diverged. Double plants are characteristic of mesh housing, monocotyledonic plants ╫ Parallel and arbital dwelling, when the veins of approximately the same power coming out of the base of the plate are merged together in its top.
Depending on the specifics of the plant growing conditions, their leaves can be modified, acquiring adaptive, adaptation features of the outer and internal structure ╫ metamorphosis. The most common modifications of the sheet ╫ spines, mustaches and philodia, and it can be metamorphosis of a whole sheet or its parts. Filodia, for example, ╫ is a sheet metamorphosis, which does not develop leaf plates, and the photosynthesis function performs the growing bleached petoo. Filodia ╫ adaptation to the lack of moisture in hot conditions and are found, for example, in many Australian acacia. Sticks of sheet origin (for example, cacti) are also a device for a lack of moisture. A mustache (for example, legumes) help climbing plants to cling to various supports. Many interesting biological adaptations develop leaves of predatory, or carnivorous, plants.
Anatomy sheet. Due to the basic functions (photosynthesis ╫ see the section "Photosynthesis" on p. 482, gas exchange, transpiration) Two types of fabrics are well developed in the sheet: the assimilation, in which photosynthesis processes are processed, and covers, regulating water evaporation and gas exchange. The sheet also has fabrics carrying out other functions: conductive tissues (water supply functions with dissolved elements of mineral nutrition and outflow of assimilation products) and mechanical tissues that give the sheet strength.
The location of the tissues in the sheet, the degree of their development, the features of the cells are greatly varied depending on the habitat conditions of the plants.
Usually, the sheet from the top and bottom side is covered with single-layer epidermum (epidermis). Under the upper epidermum is a column (panelous) mesophyll (parenchyma), consisting of one or more cell layers. These elongated cells are very tight, they contain many chloroplasts. Photosynthesis mainly occurs in the mesophyll column. Under it is a sponge mesophyll (spongy parenchyma) formed by cells of the wrong shape, between which there is a system of large interclausers filled with air. Interclausers play an important role in gas exchange and transpiration. In the cells of the spongy parenchyma, it contains significantly less chloroplasts than in the column. In some cells of the spongy mesophyll, there are dubber oxalate calcium and large mechanical support cells ╫ scleises. The sponge mesophyll is littered with the lower epidermis with the dusts (Fig. 1.3). From how widely the hydrian is discovered, gas exchange is dependent: the exchange of oxygen, CO2 and other gases, as well as aqueous pairs (transpiration) between the inside of the sheet and the surrounding sheet of air.
Fig.1.3. Hydice and cells adjacent to it in the Thamus Serpylum sheet (Thymus serpyllum). A ╫ Plan view, b ╫ in the context: 1 ╫ Front courtyard; 2 ╫ Central gap of Stute; 3 ╫ journal; 4 ╫ respiratory cavity; 5 ╫ Cuticulasposobia for Students universities RSU oil ... scientists biologists, doctors ... Reino / N. syndrome Gusev, D.M., Professor, Head ... Metals, incoming in ... 144 p. 2. Kamenskaya E.N. Psychology...
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Stroke succulents are distributed in the same ways of the family, lastone, mooring. Here we are observing the converged properties of evolution - in the same environmental conditions different plants Similar to the structure.
Metamorphosis of the kidney into a succulent organ occurs during the formation of Kachan (for example, the cabbage). First, the rosette slightly succulent leaves is formed, the kidney begins to grow hard. There are few chloroplasts in the leaves (they are greenish). After overcoming the top kidney gives a color-point escape. The appearance of succulence is explained by the Mediterranean origin.
Various sheet modifications and stem
Spinys- the leaves, its parts can be modified, the whole escape in general. The leaf origin of the spines have cacti, barbaris; from helm - in white acacia; From the cutter - at the astroker; From the edge of the leaf plate - at the coin, bodian, thistle, from the stem - a wild apple tree, a pear, coarse, lemon. The camel spines leaves of shooting origin - this proves that leaves and flowers can form on them. Spines can branch up (glyhardiya), can be curved.
Spikes- have smaller sizes. Than the rollers and the flatgua triangular shape. The formation of spines and spikes is the result of a permanent or temporary deficit of moisture.
Often the stem is compacted and turns into sheet-like organs - phillocladium, quartods, philodia.
Filocladia- Lovers or whole shoots. At the edges of Filacladodia, flowers may develop (at the healic, epiphillium, asparagus). They are difficult to distinguish the leaf and stem.
Layout - Flavored stems, long growing long. At Kokclusa Balfura Mesoladno or sickle are curved. They arise flowers and fruits.
Filodia- Flapped sheets of sheet metal sheets. They have a xeromorphic structure, are oriented with an edge to the Sun (Australian Acacia, Brazilian Aclicity). In ontogenesis, leaf plates are reduced, and the cutters turn into the philodia, which photosynthesize.
Mustache - Long retain the top growth. In the mustache can turn the upper part of the peristrid leaves (peas). At the ranks, the entire sheet plate turns into a mustache, and the assimilation function is performed. A mustache mustache are characteristic of pumpkin. Some plants in the mustache are simply modified. Warning of religious origin is characteristic of grapes and embers. The mustache can be simple (at the cucumber), complex branches (two-part - on the watermelon, plotted - at the pumpkin).
Cutting devices
Peculiar insectivorous plants. In the family of Rosyanka 4 kinds and more than 100 species. In the European region of 4 species.
Rosyanka Krugl-Oil - Fine plant peat swamps. Rounded leaves are assembled into the root spout. Top part And the edges of the sheet are seated with tentacles with a reddish glazed head. In the center of the sheet they are short, along the edges are longer. The head of the hairs surround the droplets thick, sticky. Tighted mucus. Insects attracted by glitter droplets fall onto the sheet and stick. Sheet hair is bent and collapse with mucus, which contains digestive enzymes (digest a few days).
Aldrand bubble - It dwells in the lakes and styrices of our republic. Cutting leaves consist of two semicircular, spoon-shaped halves, coated with bristles and hairs, perceiving irritation. When you touch with small water animals, the sheets of the sheet quickly fold along the medium alkaline. The leaves digest once, and then die and replace them with new ones.
Venus flytrap - Endemic of the coastal part of North Carolina. Leaves are raised above the ground, collected by a rosette around a blond. The stuff is flat and wide, the sheet plate is two rounded flaps lying at an angle to each other, equipped with spreading long, strong teeth. On the upper half of the sash - three sensitive hairs. The inner surface is assured with reddish glands containing digestive enzymes and formic acid.