Features of flowers in monocotyledonous and dicotyledonous plants. Dicotyledonous class - dycotyledonae, or magnoliopsida: description

Plants are one of the most numerous and diverse kingdoms of living nature. They give all living beings the ability to breathe clean air, producing oxygen through the process of photosynthesis. They provide people and many animals with food and nutrients, decorate our lives and make it beautiful. One of the most diverse departments of this wonderful kingdom is We will talk about them further.

Angiosperms: classification

This department includes two huge classes:

monocots;
dicotyledons.

Each of them is valuable not only for nature in general, but also for people in particular. After all, one only has to name at least a few representatives that include monocots and examples will immediately confirm their enormous practical role in human life. So, these include:

rye, wheat, oats, rice, buckwheat;
rose hips, potatoes, tomatoes, eggplants and other crops;
a huge number of medicinal herbs.

In general, the diversity of angiosperms amounts to hundreds of thousands (about 350,000). At the same time, both monocots and dicotyledonous plants, examples of which can be given for a very long time, have their own characteristics in structure, lifestyle, and life processes. We will consider one of the classes - dicotyledons. Let's figure out what characteristics these plants have, what applies to them and what their significance is.

Families of the class Dicotyledonous plants

Classification may vary. There are several options:

Takhtadzhyan system;
Rivila system;
Dahlgren and Thorne;
Cronquist.

Each took certain characteristics as a basis and divided the entire class into orders, families or subclasses. For ordinary people, such a taxonomic unit as a family is more familiar from school. Therefore, we list these most common and numerous groups that are part of the class under consideration.

Papillonaceae, or Legumes. What dicotyledonous plants are included here? For example: clover peas, peanuts, china, acacia, astragalus, chickpeas, ceratonia and others.
Rosaceae. Examples: rose hips, apple trees, pears, plums, strawberries, raspberries and others.
Cruciferous or Brassicas. A typical representative is cabbage. an example of which can also be included in this family is radish. And also: mustard, rapeseed, sverbiga. There are about 3 thousand species in total.
Compositae - include in their composition a large number of weeds, medicinal, fodder and food plants. Representatives: chamomile, dandelion, aster, cornflower, sunflower and others.
Solanaceae. A dicotyledonous plant, an example of which can be given here, is the tomato. And with it most of the important vegetable crops cultivated by humans (potatoes, eggplants and others). The very poisonous belladonna also belongs to the same family.

Less known for our country are such families as:

Laurels;
Crassulaceae;
Purslanaceae;
Grape;
Myrtaceae;
Pumpkin;
Begoniaceae;
Nut;
Willows;
Umbrella;
Birch and others.

In fact, there are quite a lot of them, so it’s difficult to list them all. Let us now consider what common features Possessed by all representatives of dicotyledons.

Features of the structure of dicotyledons

Like all higher plants, they have a stem, leaves, roots, and flowers. If we are talking about tree forms, then there is a trunk and branches. In general, the structure of a dicotyledonous plant is no different from that of others. However, there are also some peculiarities that allow one or another species to be classified specifically in this class.

These characteristic data are their distinctive feature namely from monocots, since all flowering plants are similar in their main parts, it is difficult to correctly correlate species by taxon if you do not know the special characteristics.

Main features

So, these are following parameters:

in most cases mesh.
The root system is taproot, most often perennial.
Flower structure formula: H 4 L 4 T 2+4 P 1. In general, the number of parts must be a multiple of either 4 or 5.
Between the xylem and phloem there is a layer of cambium, so many forms have a woody stem.
The leaf blade is often heavily dissected.

These signs of dicotyledonous plants do not at all indicate that all representatives are arranged in one way and not another. As elsewhere, there are exceptions and some combinations here too.

However, the most important feature is that the seeds of dicotyledonous plants have two cotyledons located opposite each other. Using peanuts or beans as an example, this can be clearly seen with the naked eye. This sign is characteristic of all representatives of dicotyledons without exception. It is for this that they got their name.

Dicotyledonous plants: examples, photos

We have already given many examples of different representatives of this class. However, they mainly focused only on those species that grow in our country. Below you can see photos of some foreign endemics for which the climatic conditions of Russia are not at all suitable. This is for example:

laurel;
delonix regal;
sundew;
sarracenia;
nepenthes;
ebony and mahogany and others.

The photo shows that they all have beautifully and brightly colored corollas. In general, almost all dicotyledons have showy flowers. However, there are exceptions among weeds.

Magnoliaceae are interesting. Each species is a dicotyledonous plant. An example of a representative of this family is star magnolia. Very beautiful and aromatic plant East. Unusual and romantic legends are made about him. Magnolias are part of the culture of many southern countries.

Spicy plants

Dicotyledonous plants also include representatives of the most fragrant, aromatic species - spicy. For example, such as:

cinnamon tree;
laurel;
coriander;
caraway;
anise;
dill;
parsley;
allspice and others.

Of course, their role in Food Industry great. Indeed, in addition to their direct purpose - improving the taste of prepared dishes and giving them a special aroma, they are also used as medicinal forms.

Umbrella

The class Dicotyledonous plants includes such a family as Umbelliferae or Celeryaceae. Their main hallmark- characteristic umbrella-shaped inflorescence. Small flowers collected in bunches of pale, rarely bright color. However, what really makes them stand out is the smell. All representatives contain a large amount essential oils, tannins, alkaloids. Therefore, the aroma of Umbrellas spreads far around in the area where they grow.

The representatives are as follows:

coriander;
carrot;
azhgon;
celery;
fennel;
parsnip;
hemlock;
hogweed;
Volodushka;
astrantia;
feverweed;
snitch and others.

There are both poisonous and very beneficial plants for humans. Many are also decorative.

Rosaceae

The most popular representative is rosehip or rose. This is a dicotyledonous plant, the example of which is always cited as soon as it is discussed. But, of course, it is not the only part of this tasty taxon. Why delicious? Because this is what includes:

raspberries;
cherry;
plum;
quince;
figs;
Apple tree;
irga;
Rowan;
apricot;
cherries;
almonds and other very appetizing representatives.

In addition to taste, they are also valuable holders of vitamins, beneficial macro- and microelements and various compounds.

Among the representatives there are also ordinary herbaceous forms: common cinquefoil, nettle, hemp, gravilate and others.

Compositae

This family includes herbaceous, rarely woody, perennial plants. There are so many representatives that they are found almost all over the globe. Asteraceae are found in both the tropics and the Arctic. This is the largest and most diverse group of all dicotyledons.

There are hundreds of examples that can be given. Let's name the most famous ones so that it becomes clear what specific plants we are talking about:

aster;
sunflower;
dandelion;
dahlia;
chicory;
marigold;
chamomile;
daisy;
serpukha;
ambrosia and others.

The most interesting representatives are:

Scalesia petiolate;
Brachylena merana.

They are interesting because they are very powerful trees up to 20/40 meters high, respectively. Scalesia has very fragrant yellow flowers collected at the tops of the branches. Many such trees form entire forests on the Galapagos Islands.

Brachylena merana is native to South Africa and Madagascar. Up to 40 meters high. The flowers are very large, collected in panicles at the tops of the branches.

Monocots and dicotyledons are two classes of Plants, the comparison of which is very often raised in the process of monitoring the study of a school biology course or in assignments for the Unified State Examination.

Monocots- This is a class of Angiosperms in which the seed embryo consists of one cotyledon. Examples of such plants are wheat, lily, tulip, sedge, palm.
Dicotyledonous plants- This is one of the classes of Angiosperms in which the seed embryo consists of two cotyledons. Characteristic representatives classes are sunflower, oak, coffee, birch, laurel, grapes, potatoes and buckwheat.

Comparison of monocots and dicotyledons

What is the difference between monocots and dicots? Monocots are considered the first angiosperms. Traces of representatives of all the main families of this class have been found in rocks of the Cretaceous period, that is, 110 million years ago. In parallel with monocotyledonous plants, traces of the presence of dicotyledonous plants were noticed on Earth. Therefore, in the world of botany, the debate about which particular class became the ancestor of the other has still not subsided.
Main characteristic feature All monocotyledons are characterized by the presence of one cotyledon in the embryo of the plant. This cotyledon is a highly modified leaf. The main characteristic of all dicotyledonous plants is the presence of two cotyledons in the seed embryo. They are located opposite. Embryogenesis of a dicotyledonous plant is associated not with the leaf, but with the root and shoot.
A monocot flower in most cases has three petals, three carpels, six stamens and six perianths. That is, the number of all elements of a flower is a multiple of three. The number of structural elements of a dicotyledonous plant is four or five.
The stem of a monocot plant is in most cases not branched: it is soft and does not have a cambium. If you cut such a stem in half, you will see that the conducting bundles in it are located chaotically and unsystematically. The stem of a dicotyledonous plant is often thickened or woody due to the presence of educational tissue - cambium. The vascular bundles in such a stem are arranged in a ring shape.
The leaves of monocots are often attached directly to the stem - without cuttings, stipules or other excesses. They are easily recognized by their parallel or arcuate venation. The leaves of dicotyledonous plants have reticulate venation because they are formed after germination of the organism from the shoot of the apical system.
The root system of monocots is always fibrous; the embryonic root in it quickly atrophies, giving the palm to the adventitious roots in providing the body with water and minerals. The root system of a dicotyledonous plant develops according to the taproot type - one main root and a number of lateral roots.

TheDifference.ru determined that the difference between monocotyledonous plants and dicotyledonous plants is as follows:

The embryo of a monocotyledonous plant has one cotyledon, and the embryo of a dicotyledonous plant has two cotyledons.
The number of structural elements in the flower of a monocot plant is a multiple of three, in a dicotyledonous plant it is a multiple of four and five.
The stem of a monocotyledonous plant is soft, while that of a dicotyledonous plant is hard, often woody. In the first version, the conducting bundles are located chaotically, in the second - in a ring-shaped manner.
The leaves of a monocot plant cover and are connected to the stem. In a dicotyledon, the leaves are attached by a petiole. The leaves of the first have parallel veins, while the leaves of the second have reticulate veins.
Monocots have a fibrous root system, while dicotyledons have a tap root system.

According to A.L. Takhtadzhyan (1987), the class Dicotyledones includes 8 subclasses, consisting of 429 families, approximately 10,000 genera and at least 190,000 species.

Morphological features

Structure seed dicotyledons: a - shell, b - endosperm, c - cotyledons(part of the embryo), d - embryo

Dicotyledons are characterized by the presence of embryo two lateral opposite cotyledons(hence the name). In dicotyledons, unlike monocots, the vascular bundles on the transverse section of the stem (trunk) are arranged in a ring shape, and between wood (xylem) And bast (phloem) there is a special educational tissue - cambium, providing secondary thickening; leaves, usually with reticulate venation: number of parts flower (sepals, stamens And carpels) is usually a multiple of 4 or 5. That is, the flower has 4 or 5 members. The embryonic root most often turns into the main one root, capable of long-term existence; The leaf blade is often dissected, its edges notched or jagged. Among dicotyledons, there are representatives with atypical characteristics, and sometimes with individual characteristics that are more characteristic of monocotyledons.

Dicotyledons as a group of flowering plants

Dicotyledons are distinguished by a variety of vegetative and reproductive organs, which makes it very difficult to clarify the true relationships between orders And families. The ancestors of dicotyledons, as well as the time and place of their origin, are not yet clear. The most common hypothesis is that the so-called. polycarpous(orders Magnoliaceae, Ranunculaceae etc.) - the most ancient original group in the evolution of angiosperms.

Meaning for humans

Dicotyledons occupy an important place in human economic activity. These include food And forage plants (potato, buckwheat, soybeans, beet, melons and many more etc.); fruit And berry culture ( grape, citrus, Apple tree, currant and etc.); oilseeds (sunflower, peanut, tung and etc.); most types trees (oak, birch, Linden and etc.); tea, coffee, cocoa and hundreds of important medicinal plants, spicy And aromatic plants (laurel, cinnamon tree and etc.); tobacco; the most important fibrous plants ( cotton, linen, hemp, jute and etc.); plants that produce rubber, gums And resins; many tanning, dyeing, essential oils and ornamental plants.

The department Angiosperms is divided into two classes: Dicotyledons and Monocots. Representatives of these classes differ primarily in the structure of the seed: the seed embryo of dicotyledons has two cotyledons, and that of monocotyledons has one (hence the name of the classes). Other differences between them are presented in table. 9.1.

However, among mono- and dicotyledons there are plants whose individual characteristics do not coincide with those listed in the table. 9.1. Thus, in the crow's eye (class Monocots) the leaf venation is pinnate, and in the plantain (class Dicotyledons) it is arcuate and has a fibrous root system. In this regard, it is possible to judge whether a plant belongs to a particular class only by a combination of characteristics.

Table 9.1. Distinctive characteristics of mono- and dicotyledonous plants.

Sign	Monocots	Dicotyledons
Root system	Fibrous, main root dies early	Taproot, well developed main root
	Herbaceous, incapable of secondary thickening, branches rarely. Vascular bundles without cambium, scattered throughout the stem	Herbaceous or woody, capable of secondary thickening, branching. Conducting bundles with a cambium are located in one large mass in the center of the stem or have the appearance of a ring
	Simple, entire, usually without petiole and stipules, often with a sheath, parallel or arcuate venation. The leaves are arranged in two rows	Simple or compound, the edges are entire, dissected or serrated, often with a petiole, stipules, reticulate or palmate venation. The arrangement of leaves is alternate, opposite
	Three-membered, less often two or four-membered	Five-, less often four-membered
Pollination	Most plants are wind pollinated	Most plants are pollinated by insects

Table 9.2 . The main characters of some families of mono- and dicotyledonous plants.

Family	Flower formula	Fetus	Inflorescence	Examples
Cruciferous or Brassicas (more than 3.2 thousand species)	H 4 L 4 T 2+4* P 1	Pod or pod	Brush, less commonly scute or panicle	Cabbage, rutabaga, radish, radish, turnip, horseradish, turnip, shepherd's grass bag, wild radish, field lily
Rosaceae (about 3 thousand species)	H 5 L 5 T P * H 5 L 5 T P 1	Assembled nut Assembled drupe Drupe Apple	Single flowers Brush Umbrella Brush Single flowers Umbrella or shield	Rosehip, strawberry Raspberry, blackberry Cherry Bird cherry Plum, peach, apricot Apple, pear, quince, rowan
Legumes, or Butterflies (about 12 thousand species)	\|H (5) L (5) T (9)+1 P 1		Head Brush	Clover Lupine, alfalfa, peas, beans, soybeans. peanuts, sweet clover
Solanaceae (about 2.9 thousand species)	H (5)* L( 5) T 5 P 1	Berry Box	Raceme or curl Raceme Single flowers	Nightshade, tomato, potato Tobacco, henbane Datura
Compositae, or Asteraceae (more than 20 thousand species)	H 0 L 5 T (5)* P 1 The calyx has become hairy or is missing.		Basket: all flowers are tubular; all flowers are reed; flowers are tubular in the center; funnel-shaped flowers are at the edges; flowers are tubular in the center; false-ligulate flowers are at the edges	Thistle Dandelion, chicory Cornflower Sunflower
Cereals, or Poagrass (more than 10 thousand species)	\|O (2)+2 T 3 P 1	Caryopsis	Complex ear panicle cob	Wheat, rye, barley Bluegrass, bentgrass, oats, male inflorescence of corn Corn

Conventions (for drawing up a flower formula): * - the flower is correct; | - the flower is wrong; O - simple perianth, consisting of only sepals or only petals; () - fusion of flower parts; * - uncertain big number flower parts; Ch - sepals; L - petals; T - stamens; P - pistils.

This principle is used when grouping all living organisms into genera, families, orders and other taxonomic categories.

The classes Dicotyledons and Monocots are divided into families. Plants of each family have common characteristics. In flowering plants, the main characteristics are the structure of the flower and fruit, the type of inflorescence, as well as the features of the external and internal structure of the vegetative organs.

Class Dicotyledons includes 418 families, about 10 thousand genera and over 190 thousand species, which is approximately 3/4 of the species of flowering plants. This class includes the most important fruits and berries (apple, pear, cherry, grapes, citrus fruits), fodder (turnips, rutabaga, clover, alfalfa), spinning (flax, cotton, hemp), oilseeds (sunflower, castor bean), and ornamental (roses, chrysanthemums, asters, dahlias), etc. They all belong to the same or different families and differ in a set of characteristics (Table 9.2).

Class Monocots forms about 122 families, over 3 thousand genera and about 63 thousand species. Monocots provide humans with bread. These include cereals (wheat, rice, rye, barley, corn, millet, etc.), some ovoids (onions, garlic, asparagus), and ornamental plants (lilies, tulips, hyacinths, asparagus, orchids).

The bulk of many hayfields and pastures in the conditions of Belarus and Russia are wild cereals - timothy, foxtail, bentgrass, bluegrass, etc.

International scientific name

Magnoliaceae Juss., (1789)

Synonyms

Liriodendraceae F.A.Barkley

Type genus

Magnolia - Magnolia

Subfamilies and genera

See text

Systematics on Wikispecies

Images on Wikimedia Commons

Magnoliaceae (lat. Magnoliaceae) - family flowering plants out of order Magnoliaceae (Magnoliales).

Distribution and ecology

Currently, magnolias are predominantly subtropical plants. A particularly large variety of species of this family is observed in Eastern And South-East Asia, as well as in the southeast North America, V Central America and on the islands Caribbean Sea. The greatest concentration of magnolia species grows in the east Himalayas, in South-West China and in Indochina. In the Southern Hemisphere, only a few species are known, occurring in Brazil and on Malay Archipelago. Among the species that come far to the north, it is worth mentioning magnolia obovate (Magnolia obovata), which can be found on Kuril island Kunashir And Japanese island Hokkaido.

Information on paleogeography

Magnoliaceae belong to the ancient flowering plants; V chalk And tertiary periods they were widespread until the modern Arctic.

Magnolia capelliii Heer And Magnolia regalis Heer- in chalk deposits Sakhalin;

Magnolia inglefieldii Heer- in the Lower Tertiary or Upper Cretaceous deposits of the basin Obi and in Urals;

Magnolia nordenskioldii Heer? - in lower tertiary deposits of Sakhalin;

Magnolia Dianae Unger And Magnolia primigenia Unger- V Oligocene sediment in the pool Volga And Don;

Magnolia paivlensis Krassn.- V Paleocene sediments of the lower Don;

Liriodendron procaccinii Unger- V Sarmatian sediments of the Black Sea region;

Liriodendron tulipiferum L.- in tertiary deposits in the Altai region.

Botanical description

Evergreens or deciduous trees, shrubs or, less commonly, vines.

Leaf arrangement next thing. Leaves simple, petiolate, pinnate, entire or lobed, usually with large deciduous stipules, bordering kidney. When the stipules fall off, they leave a scar around the node.

Flowers solitary, bisexual or rarely unisexual, radially symmetrical, large in most species (for example, magnolia macrofolia (Magnolia macrophylla) flower diameter 32-46 cm) and bright, located at the top of the branch or less often in sinus sheet). A flower usually has three sepals and six or more petals. The male part of the flower consists of many spirally arranged stamens. Stamens free or with fused filaments, usually with large microsporangium and usually a short, barely visible thread. Gynoecium(female part of the flower) apocarpous (separate), consists of many spirally arranged simple pestles. Each pistil has a top ovary with one camera and one or more ovule around the edges. All parts of the flower are clearly separated and extend from the oblong receptacle.

Flower formula: .

Fetus complex, consisting of numerous, 1-2-seeded or more, single-locular fruitlets located on an elongated or capitate dry or juicy receptacle. Seeds with a leathery or ossified shell, or with a shell that is hard on the inside and juicy on the outside; endosperm fleshy, oily; embryo small, located at the edge of the endosperm.

Magnolia Liliaceae


From left to right: Leaves ( Michelia alba ). Flower ( Watson's Magnolia). Inner part of the flower ( Magnolia naked). Green fruit ( Magnolia sprengeri ). Ripe fruit and seeds ( Magnolia cylindrica ).

Meaning and Application

Widely known as ornamental plants, often with large beautiful leaves and flowers.

Some types due to valuable wood and powerful growth are successfully used in forestry.

The bark, leaves, fruits and other parts of plants of certain species are used in folk medicine, cooking And perfumes.

Subclass Ranunculidae

It unites 3 orders and 13 families, among which the most widely known and important families are the Barberry, Ranunculaceae, Poppy, and Peony families. As an example, we give the characteristics of the type family Buttercups.

Ranunculaceae family

In the flora of the globe, there are just over 2000 species of buttercups belonging to 66 genera. In the flora of Russia, this family is represented by 516 species from 35 genera.

Buttercups are very diverse. These are mainly perennial herbaceous plants with simple palmate or pinnately dissected leaves; less often they are subshrubs and shrubs, sometimes they are lianas. Annuals are also few in number. Leaves are alternate, without stipules.

Ranunculaceae flowers are striking in their diversity of structure, but all types of structure can be arranged in a continuous series of gradual changes, and this lack of morphological hiatus speaks of the integrity of the family as a taxon. Flowers solitary or in cymose inflorescences. The receptacle may be convex, elongated or poorly defined.

The parts of the flower can be arranged in a spiral, i.e. flowers are acyclic (for example, in the swimsuit - Trollius); Some parts of the flower can be arranged in a circle (usually sepals and petals or tepals), while others (usually the androecium and gynoecium) can be arranged in a spiral, i.e. flowers hemicyclic; less often, all parts of the flower are arranged in circles (catchment - Aquilegia), i.e. flowers are cyclical.

The perianth can be simple (usually corolla-shaped) or double, consisting of elements that are not fused together, actinomorphic or zygomorphic.

Ranunculaceae are characterized by a large and indefinite number of stamens arranged in a spiral; few representatives have a fixed number of stamens arranged in several circles (catchment).

The gynoecium is mostly apocarpous, arranged in a spiral and consisting of an indefinitely large number of carpels; much less often there is only one carpel.

Ovary superior. The ovules are numerous, less often there are one or two. Fruits are mainly leaflets or nuts, rarely berries or capsules. The structure of the gynoecium and fruits underlies the classification of the family. Based on these characteristics, two subfamilies are fairly well distinguished: the subfamily Helleboroideae, which includes plants with an actinomorphic or zygomorphic perianth and having a leaflet fruit (rarely a berry or capsule), and the subfamily Anemoneaceae (Anemonoideae), which includes species with nut-type fruits.

Mostly buttercups are insect-pollinated plants, but occasionally wind-pollinated ones are also found, for example, cornflower (Thalictrum), crowberry (Actaea). According to the nature of the distribution of fruits, among buttercups there are anemochores, zoochores (in particular, myrmecochores) and hydrochores.

In general, the family is characterized by the presence of alkaloids and glucosides. This makes many representatives poisonous. Among the ranunculaceae there are medicinal plants(adonis - Adonis vernalis), ornamental plants(larkspur - Delphinium, wrestler - Aconitum, columbine - Aquilegia). Many species are honey plants.

Buttercup

Dream grass

Lumbago

Ranunculus anemone

ADONIS SPRING

Buttercup caustic

Anemone oak forest

Japanese anemone

Peonies

European swimsuit

Asian swimsuit, frying

Delphinium

Subclass Dilleniidae

One of the largest subclasses, including 31 orders and 95 families. Of the families widespread in our country, we should note the cruciferous, violet, pumpkin, willow, heather, primrose, mallow, etc. As an example, consider the Cruciferous family.

Family Cruciferae (Brassicaceae (Cruciferae))

The Cruciferous family covers approximately 3,200 species belonging to 380 genera in the flora of the globe. In Russia, the diversity of cruciferous plants is quite large and amounts to 466 species from 96 genera.

In general, the range of the family covers almost the entire globe (Cosmopolitan family), but in distribution it clearly gravitates to the temperate and cold regions of the Northern Hemisphere. The greatest species and genus diversity is concentrated in the Mediterranean and Iranian-Turanian regions (Foreign Asia), which allows us to speak of them as regions of formation and formation of this family.

Cruciferous plants are mainly herbaceous plants, among which there are perennials, biennials, and annuals. There are significantly fewer subshrubs, and there are only a few species of shrubs. Among cruciferous plants, monocarpic plants are widely represented, i.e. species that bloom and bear fruit only once in their life and die off after the seeds ripen. Cruciferous plants are one of the few families in which biennials are quite widely represented, i.e. species that in the first year develop only a vegetative rosette in the above-ground sphere, which then overwinters; a peduncle with flowers and then with fruits develops in the second year of life; After fruiting the plant dies. Another touch to the biological “face” of the family is the ability of a number of species to develop in the most extreme habitats. Some representatives of the genus Krupka (Draba) are found on the most extreme land outposts of the islands of the Arctic Ocean. In the highlands, cruciferous plants reach an altitude of 5700 m above sea level. An optional biological feature of many cruciferous plants is the ability for reserve self-pollination, which is realized in cases where for some reason (mainly due to the climatic conditions of the current year) there are no pollinating insects.

Among the signs of the vegetative sphere, one should note simple alternate leaves of varying degrees of dissection, without stipules. In the vegetative organs of cruciferous plants there are special cells (idioblasts) containing myrosin. In seeds and vegetative organs, accumulation of glycosides and caustic essential oils, alkaloids and fatty oils is also characteristic. Very important taxonomic information is the nature of the pubescence of the vegetative (as well as generative) organs. The range of cruciferous hair types is unusually wide; the main types are simple, glandular, branched, forked (Malpighian), stellate.

The general plan of the flower structure within the family is quite uniform; the differences lie mainly in the size and color of the corolla petals.

The flowers are actinomorphic, bisexual, with a double perianth, two-membered, six-circular.

The calyx is formed by four free sepals, arranged in two circles and pressed tightly against the petals during flowering. In a number of species, swellings or depressions for nectar are formed at the base of the sepals.

The corolla consists of four separate, usually yellow or white, less often purple or pink petals. The petals usually have long nails and are arranged in one circle (apparently they arose as a result of the splitting of two petal primordia). In some species the petals vary slightly in size, and then the corolla is slightly zygomorphic.

The androecium of most cruciferous plants consists of six stamens arranged in two circles: two short stamens form the outer circle, and four longer ones are located in the inner circle. Nectaries are often located at the base of the stamens.

The gynoecium is syncarpous, formed by two fused carpels with a longitudinal septum. Ovary superior; the stigma is sessile or on a style, capitate or bilobed.

Thus, overall plan The structure of a cruciferous flower can be written by the formula:

*K 2+2 C 4 A 2+(2*2) G (2)

The flowers do not have bracts or bracts and are collected, as a rule, in simple and complex racemes; True, at the beginning of flowering the inflorescence has a corymbose shape and only then, after flowering, it greatly lengthens, takes on the shape of a brush.

The main type of fruit is a pod. Sometimes it has a spout - the upper part of the ovary, devoid of ovules. The pod opens with two doors. In this case, a frame of fused edges of the carpels with a false septum stretched over it, carrying seeds, remains on the stalk. A number of cruciferous plants have indehiscent fruits that fall off entirely, or fruits that are segmented and break transversely into single-seeded segments.

Pods whose length does not exceed the width or exceeds it by no more than three times are called pods. They can also open with two valves or be indehiscent nut-shaped (Sverbiga - Bunias) or articulated (Katran - Crambe).

Cruciferous fruits carry a large amount of taxonomic information and are extremely important in their identification.

Many cruciferous vegetables have long been widely used by humans. Among the useful plants, representatives of the genus Brassica stand out: a large number of forms of cabbage (forms of Brassica oleracea), turnips and turnips (Brassica rapa), rapeseed (Brassica napus var. napus), rutabaga (Brassica napus var. napobrassica), Sarepta mustard (Brassica juncea) . Species of the genus Raphanus play a significant role in human life: the vegetable radish (Raphanus sativus var. sativus), radish (Raphanus sativus var. radicula) and the harmful weed wild radish (Raphanus raphanistrum). Watercress (Lepidium sativum) and horseradish (Armoracia rusticana) have long been cultivated by humans. In addition to vegetable and forage plants, the family also contains oilseeds - mustard, rapeseed, camelina (Camelina sativa), ornamental plants - matthiola (Matthiola), night violet (Hesperis matronalis), dye plants - woad (Isatis tinctoria). In addition to the mentioned wild radish, there are quite a lot of weeds among cruciferous crops - common cress (Barbarea vulgaris), field grass (Thlaspi arvense), shepherd's purse (Capsella bursa-pastoris), etc.

Many cruciferous plants play a noticeable and sometimes significant role in the vegetation cover of many regions.

Subclass Rosidae

Quite a large taxon, covering 39 orders and about 170 families. Below we characterize the three most species-rich and important families of the flora of our country: Rosaceae, Fabaceae and Umbelliferae.

Family Rosaceae

The Rosaceae family includes more than 3 thousand species belonging to approximately 100 genera. About 630 species from 60 genera are known in our country.

Representatives of the family are distributed almost throughout the globe, but the greatest diversity is found in the temperate and subtropical zones of both hemispheres, especially the temperate zone of the Northern Hemisphere.

The family covers a wide range of plant life forms: deciduous and evergreen trees, deciduous and evergreen shrubs and shrubs, perennial and annual herbs. Leaves are alternate, rarely opposite, simple or compound, mostly with stipules.

The flowers are solitary or in inflorescences (raceme, scutellum, umbel, etc.), mostly actinomorphic, less often zygomorphic. The flowers are mostly cyclic, less often hemicyclic, bisexual, with a double perianth, usually five-membered, less often four- or six-membered.

The receptacle is of various shapes: convex, flat or concave to varying degrees. A characteristic feature of the structure of the generative sphere of Rosaceae is the formation of hypanthium. The hypanthium arises as a result of the fusion of the tissues of the enlarged receptacle with the bases of the sepals, petals and stamens. It can be of various shapes, textures and colors and often takes part in the formation of so-called “false” fruits. Juicy and fleshy hypanthium facilitates the distribution of fruits and seeds by animals.

The calyx usually consists of five (four) free green (less often colored) sepals remaining with the fruit. Sometimes the subcup is expressed, formed by the stipules of neighboring sepals fused in pairs.

The corolla is free-petalled, consisting of five, less often four white, yellow or pink petals of varying intensity, alternating with sepals.

The androecium is always cyclic, in three or more circles, each of which has 5 or 10 stamens.

The gynoecium is apocarpous, less often coenocarpous, from a varying number of carpels (from 1 to With numerous apocarpous gynoecium, the carpels are located on a convex receptacle in a spiral.

The superior ovary predominates, less often it is semi-inferior or inferior. The ovary is single-locular or (when the carpels are fused) two-multilocular, with one or several ovules, rarely many of them.

In many Rosaceae, a nectar-bearing ridge is formed between the androecium and gynoecium, often arising from staminodes. Entomophily is characteristic.

Rosaceae fruits are very diverse. Among the apocarpous fruits, the most common are polyleaf, polynut and polydrupe. A specialized multi-nut, in which individual dry nuts are located on a fleshy, overgrown receptacle, is called frag, or strawberry; it is characteristic of representatives of the genus Strawberry (Fragaria). Cynarodium - a polynut formed by a concave pitcher-shaped fleshy hypanthium - is characteristic of the genus Rosehip (Rosa). In the subfamily Plumaceae there is a monomeric monodrug fruit. All coenocarpous fruits in the Yablonevye subfamily belong to the apple type. Rosaceae seeds usually do not have endosperm.

Rosaceae are of great practical importance, especially in temperate regions of the Northern Hemisphere. A large number of fruit and berry plants from this family are cultivated here, as well as many ornamental and medicinal species.

The Rosaceae family consists of 4 subfamilies: Spiraeoideae, Rosoideae, Maloideae and Prunoideae.

Family Papilonaceae (Fabaceae)

One of the largest families, uniting 18 thousand species from approximately 650 genera. In terms of species richness, it ranks 3rd among the angiosperm families and 2nd (after the Compositae) within the dicotyledonous class. In Russia, about 730 species from approximately 50 genera are known.

The leaves are alternate, rarely opposite, with stipules that usually remain throughout the life of the leaf. The stipules of most plants are free, some are fused with the petiole (clover - Trifolium). The leaves are usually complex: paired and imparipinnate, trifoliate, less often palmate (lupine - Lupinus) or simple.

Flowers are usually collected in inflorescences (a raceme, a head, or less often an umbrella or spike); they are zygomorphic, five-circular, five-membered, with a double perianth. The calyx is fused-leaved, irregular (two-lipped) or almost regular, with five subulate or more or less wide teeth and noticeable longitudinal veins.

The corolla is usually separate-petalled, moth-type: the upper petal (flag, sail) is the largest, two side petals (wings or oars) and two lower ones, usually fused into a so-called boat with a blunt or beak-shaped apex.

The androecium consists of ten stamens in two circles, less often there are fewer stamens; they can be free (monofraternal androecium) or fused into a tube (monofraternal androecium), however, in most species, 5 stamens of the outer and 4 stamens of the inner circles are fused with filaments, and one remains free (bifraternal androecium).

The stamen tube is called straight-cut if the free sections of the filaments bearing the anthers are of the same length, or obliquely cut if the longer lower stamens located in the middle of the tube are fused with filaments over a greater length than the lateral ones.

The ovary is superior, usually elongated, laterally compressed, unilocular, less often, due to the development of a longitudinal false septum, bilocular (many types of astragalus). A column (stylodium) extends from the apex of the ovary at an angle, often with a beard of hairs under an oblique, less often capitate, stigma. The ovary is surrounded by a stamen tube, the free ends of the stamen filaments are located around the stylode. The stamens, together with the gynoecium, are located inside the boat. Many species are proterandric. The flowers are entomophilous and have a number of peculiar adaptations to pollination by insects. The anthers open before the buds open, and the pollen accumulates in the boat, which, together with the oars, sinks under the weight of an insect that has landed on the flower; at the same time, the pistil and stamens are released with force, pushing the pollen out of the boat. In some plants (peas), self-pollination occurs even in the bud.

The fruit is a bean. The shape of the beans is very diverse. Depending on the number of seeds and the nature of their dispersion, beans can be multi-seeded, opening with two valves from above along the ventral suture and the midrib of the carpel (pea, pea); indehiscent, containing a small number of seeds (clover); pseudobilocular, dehiscent valves (a number of astragalus); articulated (vyzel, kopeck); single-seeded, indehiscent, nut-like (sainfoin). The seeds are without endosperm and contain a large embryo with two massive cotyledons.

The roots of a significant part of legume species have nodules, which arise as a result of the proliferation of parenchymal tissue of their roots due to the introduction and endogenous dispersal of nitrogen-fixing bacteria from the genus Rhizobium. They are able to use free molecular atmospheric nitrogen, introducing it into the biological cycle of substances in ecosystems. Protein substances produced by nodule bacteria are used by leguminous plants. When roots and other parts of plants die, accumulated reserves of bound organic nitrogen enter the soil and, after decomposition and processing by other types of bacteria, become sources of nitrogen nutrition for green plants. The high protein content in all organs distinguishes representatives of this family from plants from other families.

Representatives of the family play important role In human life. The high content of proteins, fatty oil and starch in the seeds determines their high nutritional and feed value. However, legumes are known not only as food, oilseeds or fodder plants. This includes a whole range of valuable medicinal, vitamin-rich, decorative and technical species.

Family Umbelliferae (Apiaceae)

Along with the Cruciferae, Apiaceae are one of the few natural families of flowering plants known and distinguished by man since ancient times. Belonging to this family very rarely raises any doubts even among novice botanists.

In the flora of the globe, more than 3,000 species of Umbelliferae, belonging to approximately 300 genera, are currently known. In the flora of Russia, the family is represented by 268 species from 96 genera.

The family is practically cosmopolitan, but the umbelliferous family gravitates mainly to the temperate zones of both hemispheres.

These are mainly herbaceous plants (perennials, biennials and annuals), less often - subshrubs, shrubs or small trees. Among the Umbelliferae there are quite a few monocarpics. Shoots usually have clearly visible thickened nodes; internodes are often grooved or ribbed, often hollow inside. Most plants have secretory reservoirs in all organs. The leaves are simple (less often complex), alternate, with widened or swollen bases in the form of stem-enveloping sheaths, without stipules. The leaf blade is rarely whole (in the frogwort - Bupleurum), usually it is palmately or pinnately dissected many times.

The flowers are small, collected in inflorescences such as a complex umbrella, less often - in simple umbrellas or capitate inflorescences. At the base of the rays of simple inflorescences there are often small leaves, which by their origin are the covering leaves of the marginal flowers of the inflorescence. These leaves form what is called an involucre. In complex umbrellas, a distinction is made between the involucre and the involucre (leaves at the base of the rays of the second order). The presence or absence of an involucre or involucre and, if present, the number and shape of leaflets is an important taxonomic character in the family.

Umbelliferous flowers are mainly actinomorphic, or the marginal flowers of the inflorescence can be zygomorphic due to the uneven growth of the petals. The flowers are usually bisexual, five-membered, four-circular.

The perianth is double, but the calyx, as a rule, is underdeveloped or represented by 5 teeth; very rarely it consists of 5 free small sepals or is not developed at all.

Corolla of 5 free, often white or greenish, less often yellow, pink or bluish short-legged petals, often appearing notched at the apex due to the limb ends narrowed and tucked inside the flower. The petals are attached to the upper part of the ovary. The corolla lobes alternate with sepals.

The androecium consists of five stamens alternating with petals. The filaments are long, bent inside the flower in the bud and only later bent outwards. The flowers are usually proterandrous. The anthers fall off soon after the flowers open.

The gynoecium is coenocarpous, consisting of two carpels; each nest of the bilocular ovary contains one developed ovule. There are two columns, with expanded glandular sub-pillars (nectaries) at the base. Stigmas are capitate. The ovary is often semi-inferior, since all parts of the flower are attached below the sub-columns that make up the apex of the ovary.

The following flower formula reflects the structure of the vast majority of umbellifers:

*K 5 C 5 A 5 G (2)-

The focus of the most valuable taxonomic information is the fruits of Umbelliferae. The fruit is fractional, splitting into two single-seeded mericarps hanging on the branches of a bipartite column, or carpophora, formed from vascular bundles of the marginal parts of the carpels. The fruit of umbelliferous plants is called visloporp, or two-seeded. Each mericarp usually has five primary longitudinal ribs in which vascular bundles are located. Sometimes secondary ribs develop in the hollows between these primary ribs. The shape and size of the fruit, the outline of its cross section, the nature and size of the ribs, the presence of various kinds of spines, hooks and other devices for propagation on them, the details of its anatomical structure are the most important taxonomic features that are guiding in the taxonomy of this taxonomically difficult family.

The seed fits tightly to the pericarp or grows together with it. In addition to the embryo, the seed contains a well-developed endosperm, the shape of which also has taxonomic significance.

Apiaceae often play a significant role in the vegetation cover of many regions. Being often quite powerful plants, they often add specific features to plant landscapes. Thus, in the meadow steppes of the European part of Russia and Siberia, white aspects during flowering are created by the species of gorychnik (Peucedanum) and gillweed (Sasill). In deciduous forests, the common duckweed (Aegopodium podagraria) often dominates the herbaceous layer. In a number of regions of Central Asia, unique landscapes are formed by numerous ferulas (Ferula).

The richness of essential oils, resins and gums, alkaloids and some other groups of organic substances has determined the long cultural history of many species. These include vegetables (carrots - Daucus carota, parsnips - Pastinaca sativa, celery - Apium graveolens, parsley - Petroselinum), essential oils (coriander or cilantro - Coriandrum sativum, cumin - Carum carvi, anise - Anisum vulgare, dill - Anethum graveolens) and medicinal plants (anise, angelica - Archangelica officinalis, ammi visnaga, ferula - Ferula). Some umbrellas are very poisonous (speckled hemlock - Conium maculatum, poisonous hemlock - Cicuta virosa).

Subclass Lamiidae

The largest group by number of species, including many highly specialized taxa of flowering plants. Unites 11 orders and 66 families.

Family Scrophulariaceae

This family, along with the next two, is often classified in the order Tubiflorae. This fairly natural group includes about 10 families (in addition to the Norichnikov, Borachnikov and Solanaceae families described below, this includes, for example, the well-known Lamiaceae, Sinyukhova, and Convolvulaceae families), characterized in general terms by four circular five-membered flowers with a double perianth and a sphenolate corolla .

The Norichnikov species include about 3,000 species from more than 200 genera. More than 370 species from approximately 35 genera are known in Russia.

Representatives of the family are distributed almost throughout the globe, but mainly in temperate regions.

The leaves are simple, without stipules, alternate (less often opposite or whorled), usually entire, less often pinnately dissected (genus Mytnik - Pedicularis). Anatomical features include the presence of a second (internal) strand of phloem in the vascular-fibrous bundles; thus, the bundles are bicollateral.

Flowers on pedicels without bracts, solitary or in inflorescences (tassel, spike, etc.). The flowers are four-circular, bisexual, with a double perianth, zygomorphic, sometimes almost actinomorphic (mullein - Verbascum), quite diverse due to the reduction and fusion of some organs.

The calyx is fused-leaved, of five, less often of four sepals, usually zygomorphic, remaining with the fruit.

The corolla is sphenoletal, usually of five, less often - of four petals. Corolla tube of different lengths and shapes, sometimes with a spur (flaxflax - Linaria). If the corolla is two-lipped, then the upper lip consists of two and the lower lip consists of three petals.

The androecium usually consists of four two-strong stamens, the fifth stamen is sometimes in the form of a staminode. Less commonly, there are five (mullein) or two (Veronica) stamens. Stamens alternate with petals, their threads grow to the corolla tube.

The gynoecium is coenocarpous, consisting of two carpels fused in the median plane.

The ovary is superior, bilocular, with numerous ovules. At the base of the ovary there is usually a nectary. Style with capitate or bilobed stigma. The fruits are capsules, less often - berries or drupes.

Norichnikov do not have much practical significance for humans. Glucosides accumulate in them, which is why they are not eaten by animals. However, some plants have medicinal value (mullein, foxglove - Digitalis, toadflax - Linaria); a number of species are bred as ornamental (calceolaria - Calceolaria, lipweed - Mimulus, snapdragon - Antirrhinum); many common burweeds are weeds (rattle grass, eyebright - Euphrasia).

Borage family (Boraginaceae)

There are more than 2000 species in the family from almost 100 genera. In Russia, 187 species belonging to 30 genera are known.

A widespread family, but mainly in the dry subtropical regions of the Northern Hemisphere.

The family includes a wide range of life forms: herbs (annual and perennial), subshrubs, and in tropical regions - vines, shrubs and trees.

The leaves are simple, alternate, usually entire and without stipules, usually rough with stiff hairs. However, the presence of various kinds of hard hairs is very characteristic of the entire vegetative sphere and borage fruits.

Flowers are usually actinomorphic (rarely zygomorphic), bisexual, five-membered, four-circular. They are usually without covering leaves and bracts and are collected in whorls or dichasias of whorls (this type of inflorescence is very characteristic of borage).

Double perianth. The calyx is sphenoid, but the sepals often grow together only at the base. The calyx remains with the fruit, sometimes expanding.

The corolla is sphenolate, with a long (lungwort - Pulmonaria) or short (forget-me-not - Myosotis) floral tube. The shape of the corolla is varied, occasionally it can be zygomorphic (bruise - Echium). In the throat of the corolla, petal outgrowths often form in the form of folds, teeth or tufts of hairs (the so-called corolla), blocking access to the flower by non-pollinating insects and protecting the internal parts of the flower from rainwater.

Androecium of five stamens growing to the corolla tube and alternating with petals.

The gynoecium is coenocarpous, consisting of two carpels. The ovary is superior, initially bilocular, with two ovules in each ovule; subsequently, false septa appear between the ovules and the ovary becomes four-lobed. There is one style, emerging from the space between the lobes of the ovary (i.e., gynobasic). The stigma is entire, less often lobed. A solid or lobed nectar-bearing disk is formed around the ovary.

The fruit is fractional - coenobium, in most cases consisting of four falling single-seeded nut-like parts - erems. Eremes in many species have an aneurysm formed from the receptacle or from nectaries and serves to attract ants that spread them. Seeds without endosperm. Some tropical species have juicy, drupe-like, indestructible fruits.

As in the case of borage, there are very few useful plants among borage. A number of plants are honey plants (lungwort, bruise); There are medicinal and ornamental plants (heliotrope - Heliotropium, forget-me-not, comfrey - Symphytum), weeds and poisonous ones are also known (bruise, blackroot - Cynoglossum, crooked flower - Lycopsis).

Nightshade family (Solonaceae)

The family includes about 2.5 thousand species belonging to 80-90 genera. In our country, only about 35 species (of which 20 are cultivated) from 10 genera are found, but their economic importance makes it necessary to consider this family in our short course.

Solanaceae are common in temperate, subtropical and tropical zones, but they are especially abundant in South and Central America.

In temperate latitudes, nightshades are represented mainly by herbaceous plants, while in tropical regions shrubs (sometimes climbing and climbing) and trees predominate.

Solanaceae have alternate simple leaves, whole or dissected, without stipules.

Like Norichinaceae, they have bicollateral vascular-fibrous bundles with internal phloem.

The flowers are externally actinomorphic, but often, due to the oblique position of the ovary in relation to the median plane of the flower, they are slightly zygomorphic. Inflorescences are cymose, apical or axillary (curls), rarely solitary flowers.

The flowers are bisexual, four-circular, with a double perianth.

The calyx is fused-leaved, with 5, less often 4 or 6, leaflets, preserved during the fruit; sometimes it swells after flowering and completely covers the fruit (Physalis).

The corolla is sphenoletal, consisting of five leaflets fused to varying degrees; usually it is wide open, tubular-wheel-shaped, bell-shaped, funnel-shaped, less often - tubular or bilipped.

Androecium of five stamens attached to the corolla tube and alternating with its lobes. The anthers are usually immobile, arranged in a cone around the style and dehiscent by a longitudinal slit or at the apex. In the type, the anthers are four-lobed, but sometimes, as a result of destruction of the partition between the nests, they are two-lobed.

The gynoecium is coenocarpous, consisting of two carpels. The ovary is superior, entire, bilocular, less often - single-locular (sometimes, due to the development of false septa, three- or five-locular), with numerous ovules in each nest. The placentas, to which the ovules are attached, are massive, attached to the septum separating the nests. Single style, with entire or bilobed stigma.

The fruit is a berry, a drupe (rarely a drupe-like one) or a capsule.

Many nightshades are poisonous due to the presence of poisonous alkaloids in them. Solanaceae include many economically important cultivated plants: food (potatoes - Solanum tuberosum, tomatoes - Lycopersicum esculentum, sweet or capsicum peppers - Capsicum annuum, eggplant - Solanum melongena), medicinal (belladonna - Atropa belladonna, henbane - Hyoscyamus niger, scopolia - Scopolia carniolica), decorative (fragrant tobacco - Nicotiana affinis, petunia - Petunia hybryda, physalis) and technical (real tobacco - Nicotiana tabacum and shag - Nicotiana rustica).

Subclass Asteridae

One of the largest subclasses of flowering plants in terms of volume. The most widespread and famous families are Campanaceae and Asteraceae.

Family Compositae (Asteraceae)

Asteraceae is one of the largest families of flowering plants, occupying second place (after orchids) in terms of species diversity in the flora of the globe (in addition, it is the largest family within the Dicotyledonous class). It includes 25 thousand species from approximately 1300 genera; In Russia, about 2000 species from approximately 120 genera are known.

Most Asteraceae are perennial or annual herbs, sometimes subshrubs and subshrubs; in tropical and subtropical regions there are shrubs and low trees, vines, succulents (stem and leaf).

The leaves are simple, usually without stipules, with entire or to varying degrees dissected leaf blades; sometimes the leaves are compound. The leaf arrangement is almost always alternate, less often opposite or whorled. Often the leaves are in a basal rosette. Many species have laticifers in all vegetative organs or resin ducts.

Flowers are always in inflorescences - baskets, which can be collected into more complex inflorescences (complex corymb, panicle, etc.). The basket is a rather complex type of inflorescence. The basket bed, which is an expanded axis of the inflorescence, is flat, convex or concave, mostly made, less often hollow, smooth, pitted, bare or covered with covering leaves (bracts) in the form of films, bristles or hairs.

On the lower part of the basket there are apical leaves close together, which together form an involucre. The involucre leaves can be of various shapes, colors and consistencies: herbaceous green, membranous, membranous, with or without appendages, single-row, double-rowed or multirowed, imbricated, etc. The structure and relative position of the involucre leaves, coupled with the shape of the lower part of the basket axis, determines the shape wrappers in general. The innermost leaflets of the involucre are the covering leaves of the marginal (i.e., morphologically lower) flowers of the basket. The number of involucre leaflets, their arrangement, shape and color, along with the shape and features of the basket bed, are important taxonomic characters in the taxonomy of the family.

The baskets usually contain many flowers, less often they have one or two flowers. Flowers in the type are bisexual, but often, due to underdevelopment of the androecium or gynoecium, they are female or male, and in their absence - asexual. The flowers are sessile, either all the same (homogamous baskets), or the middle flowers of the basket differ from the marginal ones (heterogamous baskets), actinomorphic or zygomorphic, four-circular, five-membered, with a double perianth; ovary inferior.

The calyx of Asteraceae is atypical and consists of a membranous border at the apex of the ovary; sometimes it consists of five membranous sepals, often it is invisible, and the sepals are modified into attachments, bristles or hairs that form a pappus (pappus), which grows into a fly during the fruit.

Based on the nature of symmetry and fusion of petals, the presence or absence of androecium and gynoecium, five types of flowers are distinguished in the family:

1. Tubular - with a long tube, usually widening upward, with a short five-toothed limb formed by the free tips of the petals. The flowers are bisexual, less often unisexual, actinomorphic. The tubular flower is the original type in the family.

2. Reed - bisexual, with a short tube and a lamellar five-toothed bend. The reed corolla is derived from the tubular corolla; a one-lipped corolla is formed, from the tube of which one tongue extends, having five denticles along the edge, corresponding to the participation of all five petals in its formation. The flower is thus zygomorphic.

3. Funnel-shaped - asexual, with a long, curved, highly expanded corolla tube with a large number of teeth due to partial splitting of the free ends of the petals. The flowers are zygomorphic, found only on the periphery of the baskets and serve the function of attracting pollinating insects.

4. Bilabial - bisexual or unisexual, with a rather long tube, from which extends an upper lip consisting of two free teeth and a lower lamellar lip in the form of a tongue with three teeth at the top. The flower is zygomorphic.

5. False-lingulate - derivatives of bilabial flowers by shortening the tube and reducing the upper lip; usually pistillate, less often asexual. The false tongue is formed by three petals, as indicated by the three denticles at its apex. The flowers are zygomorphic, located only in the marginal part of the basket.

The structure of the androecium of Asteraceae is original and has no analogues in other families of flowering plants. It consists of five stamens alternating with petals. The bases of the stamen filaments grow to the corolla tube. The anthers are motionless, linear, mostly fused into a tube surrounding the style. Often, anthers have appendages arising from the connective tissue or anther bases. The anthers open into the cavity of the tube with longitudinal slits, and the pollen falls on the stigma, covered with hairs.

The gynoecium is pseudomonomeric, consisting of two fused carpels forming an inferior unilocular ovary with a single ovule attached to the bottom of the ovary. The style is long, filiform, divided at the top into two lobes, under which there is sometimes a thickening or a ring of sweeping hairs. The fruit is an achene with a tuft of hairs attached directly to the apex of the ovary or rising above the fruit on a spout developing from the apex of the ovary. Sometimes boz tuft achenes (sunflower). The spread of fruits is facilitated not only by the pappus, but also by the involucre leaves, if they are equipped with hooks or other outgrowths. A single seed without endosperm and with a large embryo occupies almost the entire cavity of the fruit and often fuses with the pericarp.

Some Compositae (dandelion - Taraxacum, hawkweed - Hieracium) are characterized by apomixis, i.e. the development of seeds without fertilization. Asteraceae are of great economic importance as food, fatty-oil, aromatic, medicinal, ornamental and even rubber plants.

The class of monocotyledonous flowering plants includes about 80 families and more than 60,000 species. These are predominantly herbaceous plants (wheat, rye, lily, lily of the valley, tulip, orchis, sedge, timothy, oats, corn, feather grass). Trees, shrubs, lianas and epiphytes of monocots are found only in the tropics (bamboo, palm, aloe, pandanus, monstera, dracaena, orchid).

Among them there are plants reaching a length of 60-70 m (for example, palm tree, royal palm), and a climbing palm calamus rattan grows up to 150-180 m in length. However, there are very small plants, for example various species duckweeds 3-6 mm in size.

Many monocots lead an aquatic lifestyle (pondweed, cattail), semi-aquatic (chastuha, callus, calamus, cyperus-papyrus), some live in tree crowns as epiphytes (orchids, bromeliads, chlorophytums).

In the class of monocots there are many beautifully flowering plants, widely represented in indoor or garden floriculture (gladioli, daffodils, hyacinths, irises, tulips), a number of species are grown as ornamentals due to beautiful leaves, stems (cordilina, tradescantia, monstera, philodendron, dieffenbachia, scindapsus, asparagus, agave, aloe).

Many representatives of monocots were included in cultivated plants.

These include cereals, as well as onion, garlic, pineapple, sugar cane, palm trees -date, coconut, sugar, betel, Seychelles etc. All of them have served people for nutrition and many other purposes since ancient times.

Lily family

Lilies are the oldest cultivated plants. On the one hand, many wild lilies are so good that they are still grown in gardens in their original form; thousands of varieties of lilies and tulips have been bred. On the other hand, onions and garlic have been cultivated by humans for 6 thousand years and are no longer found in the wild.

This is a family of monocots. Therefore, first of all, we will remember by what characteristics monocots differ from dicotyledons. Then we will find out why beautiful lilies, pungent garlic and agave (aloe) growing in every home belong to the same family. And we will find out which representatives of lilies are beautiful, which are useful, and which are poisonous.

General characteristics of the lily family. This large family contains about 250 genera and almost 4 thousand species, distributed on all continents, especially on the dry and sunny plains of the Mediterranean and Central Asia. Many species are known only in culture. Lilies are herbaceous plants.

These are perennial bulbous or rhizomatous herbaceous plants. Adventitious roots extend from the bulbs, forming a fibrous root system. Lily leaves are simple, with arcuate or parallel veins.

The flowers are regular, with a simple perianth of 6 leaflets, which are arranged in two circles. Most often the perianth is septate, but it can also be fused-leaved (in lily of the valley). There are also 6 stamens and also in two circles of 3. But there is one pistil, but the ovary is three-lobed. All parts of a flower are multiples of three.

Large and bright flowers lily - solitary. Small flowers in lilies, racemes are collected in inflorescences (lily of the valley, tiger lily, kupena, aloe) or umbellate (garlic, onion). Fruit - capsule (tulip, lily, onion) or berry (asparagus, raven eye, lily of the valley). The seeds contain a small embryo and a highly developed endosperm.

Wild representatives of lilies. Many lilies bloom early in the spring. Their bulbs have accumulated a significant reserve nutrients, so in the spring they quickly begin to grow, bloom, and bear fruit. Summer, autumn and winter they exist in the form of bulbs.

In our country, the most famous are goose onions and blueberries. The flowers of the goose onion are yellow, and the flowers of the scilla are blue, light blue, and less often purple. Goose onion found in forests and fallow fields. Scilla - on the edges, in oak forests, thickets of bushes, common in the forest-steppe zone. These plants, having multiplied, form entire lawns of soft yellow or blue flowers.

The species name of the scilla is Siberian, but it is erroneous. The scilla originates from the Black Sea region, grows in deciduous forests and has nothing to do with the coniferous forests of Siberia. But in Siberia you can see another wonderful flower - dog tooth, or kandyk.

Lilies They grow mostly in the mountains, on forested and open slopes. The white lily comes from southern Europe. It is a honey plant and a medicinal plant. In forests middle zone red lily and curly lily (saranka) are growing. Unfortunately, these beautiful plants are endangered and protected plants, just like checkerboard hazel grouse.

Tulips grow in deserts and semi-deserts, in steppes (they easily tolerate summer drought). In our country - in the steppes and deciduous forests. Some species are listed in the Red Book.

Economic importance of the family. First of all - this onion . All onions have a characteristic “onion” smell. Moreover, it is not the flowers that smell, but all the vegetative parts of the plant. The inflorescence of many onions is a simple umbrella, it can be very beautiful and is used in decorative purposes. Onions are valuable because they contain many vitamins (C and B) and phytoncides, which belong to the group of antibiotics!

Garden onion (bulb) grown for its juicy bulb. It comes from Iran. Known in culture since Ancient Egypt. Onion- perennial onion from China. Its bulbs are small but very tasty thick cylindrical leaves that can be cut several times during the summer. The leaves are also used in the most delicate of onions - chives. They are thinner than those of spring onions, but they appear early in the spring.

Garlic originally from Central Asia. Its bulb consists of individual baby bulbs. Flowers are rarely produced. Instead, small bulbs develop in the inflorescence. Wild lilies are used as food wild garlic (bear onion).

Asparagus officinalis - a wild plant, but also grown in culture. Young underground shoots are a valuable vegetable. Adult shoots are decorative, grown in gardens. How houseplants grow another type of asparagus - asparagus.

Also used in indoor gardening aloe, dracaena.

If lilies did not exist, our gardens would look completely different, because these are tulips, And lilies, And hyacinths.

The homeland of tulips is the Mediterranean (their name comes from the Persian “turban”), although the country where tulips are especially intensively cultivated is Holland.

If the flowers of thousands of varieties of tulips created by man are beautiful, but do not have a special smell, then hyacinths and most lilies have a very strong smell. Hyacinth means “flower of rain” in Greek. In its homeland, Asia Minor, it blooms during the rainy season, and here in the spring.

Lilies are the closest relatives of tulips. Lily in art is a symbol of purity. Hundreds of varieties have been bred that decorate gardens from late June until autumn. Many varieties of lilies are grown in greenhouses all year round especially for cutting - for bouquets.

Medicinal and poisonous plants families. Among the cultivated and ornamental lilies there are many medicinal ones. First of all, these are onions and garlic, which contain substances that kill bacteria. The well-known “centenarian” aloe tree, used for wound healing and gastrointestinal diseases.

No less famous lily of the valley - perennial with rhizome and adventitious roots. Lily of the valley has only two leaves, the fragrant inflorescence is a raceme. Unlike most lilies, its perianth leaves grow together to form small bells. The fruit is a berry. Be careful, they are poisonous! But in medicine, lily of the valley preparations are widely used in the treatment of heart diseases. Lily of the valley is also used in perfumery. Lily bulbs are used in cosmetology.

Many medicinal plants are also poisonous. For example, bought, hellebore.

Colchicum, growing in the Caucasus mountains, it is often grown in gardens, because it forms beautiful flowers in the fall, until November. The entire plant is poisonous, even the water in which its branches stood. In medicine, it is used to treat rheumatism of the joints. A unique substance (colchicine) is extracted from it, which is indispensable for chromosomal studies.

Among the poisonous lilies and raven eye - forest plant with a whorl of 4 leaves and one large black berry.

Gerbera is a perennial plant of the Asteraceae family, dicotyledonous class.

All angiosperms are divided into two large classes: dicotyledonous And monocots. The name of the classes reflects the most important difference between these groups: dicotyledons have two cotyledons in the seed, which serve as a storehouse of nutrients for the plant embryo, and monocotyledons have only one cotyledon. In addition, these plants are different internal structure shoots, leaves, roots and flowers. The classes of dicotyledons and monocotyledons are divided into families, genera and species.

Plant division

For the first time, the division of plants into monocots and dicotyledons was proposed in the 18th century. English scientist D. Ray, he systematized plants according to their characteristics. For a long time It was believed that monocots were more primitive than dicots.

Oriental hyacinth has all the typical characteristics of monocots

However, now scientists agree that monocots are a younger and more advanced group, the evolution of which has taken the path of simplifying the structure of vegetative organs. Apparently, they originated from dicotyledons, but this happened at the very early stages of evolution, and then the two groups developed in parallel. It may very well be that the ancestors of monocots were herbaceous aquatic plants, similar to modern representatives of the Nymphaeaceae family.

Main Differences

Monocots and dicotyledons differ not only in the structure of the seed. They have other significant differences. In dicotyledons, the leaves are extremely varied in shape and usually have reticulate venation, while the leaves of monocotyledons are narrow, with a solid, uncut edge; the veins in the leaf are arranged parallel or arched.

In dicotyledonous stems, bundles of conductive tissue are arranged in a ring-like manner. In addition, there is educational tissue (cambium), due to which the stem increases in girth with age.

Strawberries have the characteristic shape of leaves, flowers and roots for dicotyledons.

In the stems of monocots, the vascular bundles are arranged randomly, the cambium is almost completely absent, the stem branches little and does not grow in thickness. Therefore, most monocots are herbaceous plants, the only exception being palm trees, but even in them, the thickening of the trunk occurs in a completely different way than in dicotyledons.

Dicotyledons are characterized by the presence of a powerful central root growing from the root of the embryo. Monocots are more characterized by a fibrous root system, consisting of a large number of adventitious roots without a main root. A dicotyledonous flower usually has 5 petals and sepals, and a monocotyledonous flower has 3 (or their number is a multiple of three).

Application of dicotyledons

The dicotyledonous class is the largest plant group, numbering over 200 thousand species from 350 families. Representatives of dicotyledons in all life forms are found on all continents of the Earth and make up the bulk of the plant cover of our planet. Among the dicotyledons used by humans are: fruit and berry crops, most types of medicinal plants, spicy and aromatic plants, almost all trees, food and fodder crops, etc.

Delphinium is a dicotyledonous plant, often grown in gardens and flower beds

Applications of monocots

Monocots also live throughout the globe. In the steppe belt of the Earth, monocots perennial herbs constitute the bulk of the plant mass. Despite the fact that they are not as diverse as dicotyledons (they include only about 60 thousand species from 80 genera), monocotyledonous plants play an important role in human life. After all, these include cereals (wheat, rye, oats), which provide food for humans and animals; palm trees (coconut, date, etc.), providing people with oil, edible fruits, and material for making ropes and paper; ornamental plants (tulips, lilies, hyacinths, orchids); many medicinal herbs.

There are thousands of varieties of garden tulips different forms and shades, this is the result of a complex process of crossing species

Flowering plants are divided into two classes - dicotyledons and monocotyledons. The main characteristics of the dicotyledonous class:

The seed embryo has two cotyledons;

The root system is usually taprooted;

The growth of the stem in thickness is ensured by the cambium (lateral meristem);

The leaves are usually reticulated, with the exception of plantain;

The flowers have a double perianth.

The number of flower components is a multiple of five, sometimes four;

The main life forms are trees, grasses, and shrubs.

Signs of the monocot class: the embryo has one cotyledon; fibrous root system; the stem does not grow in thickness because it does not have a cambium; leaves are simple, with parallel or arcuate veins, with the exception of crow's eye; the number of flower components is a multiple of three; perianth simple.

Classes of flowering plants are divided into divisions, orders, families, genera, and species.

Some families included in these classes are presented in Table 5.

Family	Life form	Flower formula	Fetus	Representatives	Meaning
Compositae		Ch(5)L5TnP1-tubular flowers Ch(5)L5TnP1-reed flowers	Achene	Sunflower, chamomile, aster	Food, ornamental crops, honey plants
Solanaceae	Herbs	W(6)L(5)T(5)R1	Berry, box	Potatoes, mats, dope, white	Food, fodder, ornamental crops. Poisonous plants are used for cooking medicines
Legumes	Shrubs, herbs	TC(5)L1+2+(2)T(9)+1P1	Bean	Peas, red clover, lupine, beans, alfalfa	Forage and food crops, honey plants, weeds
Rosaceae	Trees, shrubs, herbs	Ch(5)L5TpPg ch5+5l5tpp1	Multi-nut, drupe, apple, complex drupe	Cherry pear raspberry, apricot, apple tree, rose nick	Ornamental, medicinal plants, fruit trees
Cruciferous	Herbs	Ch4L4T4+2P1	Pod or pod	Cabbage, radish, radish, rutabaga	Food and feed crops, honey plants, weeds
Liliaceae	Herbs	O3+3T3+3P1	Berry, box	Onion, garlic, lily, tulip	Food crops, medicinal, ornamental plants
Cereals	Herbs	О2+2Т3П1	Caryopsis	Wheat, rye, rice, oats, corn, bamboo, bluegrass	Grain and fodder crops, weeds

Cultivated plants arose as a result of the domestication of wild species and subsequent centuries-old selection.

The main contribution to the theory of the origin of cultivated plants was made by N.I. Vavilov.

Monocots and dicotyledons

He linked the genetic diversity of plants to their places of origin. Vavilov identified seven centers of diversity and origin of cultivated plants (now it is believed that there are more of them):

1) South Asian (India, Indochina, Indonesia) - rice, mango, eggplant, citrus fruits, etc.;

2) East Asian (Central China, Japan, Korea) - millet, soybeans, buckwheat, onions, apple, pear, tea, etc.;

3) South-West Asian (Central Asia, Transcaucasia) - rye, beans, peas, carrots, turnips, etc.;

4) Mediterranean - olives, cabbage, beets, oats, dill, parsley, caraway seeds, etc.;

5) Abyssinian, or Ethiopian - sorghum, durum wheat, barley, bananas, flax, etc.;

6) Central American (Mexico and the Gulf Islands) - corn, beans, cocoa, pumpkin, pepper, tomato, sunflower, etc.;

7) South American - potatoes, cinchona, tobacco, peanuts, pineapple, hevea (from which rubber is obtained), etc.

Plant domestication began in these areas.

Then they were settled and acclimatized in other regions of the Earth.

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4.5.2. Monocots and dicotyledons

Flowering plants are divided into two classes – dicotyledonous And monocots.

Monocots: characteristics, features, significance

The main characteristics of the Dicotyledonous class are the following:

– there are two cotyledons in the seed embryo;

– the root system is usually taprooted;

– growth of the stem in thickness is ensured by the cambium (lateral meristem);

– leaves, usually with reticulate venation. The exception is plantain.

The flowers have a double perianth. The number of flower components is a multiple of 5, sometimes 4.

The main life forms are trees, grasses, and shrubs.

Signs of the class Monocots:

– the embryo has one cotyledon;

– fibrous root system;

– the stem does not grow in thickness, because

has no cambium;

– leaves are simple, with parallel or arcuate veins. The exception is the raven eye.

The number of flower components is a multiple of 3. The perianth is simple.

Classes of flowering plants are divided into: divisions, orders, families, genera, species.

Some families included in these classes are presented in table form:

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Comparison of dicotyledons and monocotyledons

In the department of Angiosperms (Flowering) plants, there are two classes - Dicotyledons and Monocots.

Dicotyledons appeared earlier, and subsequently monocotyledons evolved from them. There are more species of dicotyledonous plants. Many features are common to both classes. However, they have significant differences in a number of characteristics.

Distinctive features of dicotyledonous plants:

The seed embryo has two cotyledons.

The seed's supply of nutrients is stored either in the embryo or in the endosperm. The embryonic root gives rise to a well-developed main root. Tap root system. Leaves with pinnate or palmate venation. The conductive tissue of the stem has a pronounced ring structure.

Thanks to the ring layer of cambium, the stem grows in thickness. There are many both woody and herbaceous forms.

Distinctive features of monocots:

The seed embryo has one cotyledon.

What are monocots and dicotyledons

The supply of nutrients is in the endosperm. The germinal root is poorly developed. During germination, adventitious roots emerge from the stem. Fibrous root system. Leaves with parallel or arched veins. The leaf petiole is either almost undeveloped or is a leaf sheath. The conductive tissue of the stem consists of bundles.

There are no cambium rings like in dicotyledons. Mostly grass.