Formula of flowers of multi-colored plants. Outline of a biology lesson (6th grade) on the topic: Drawing up flower formulas and reading diagrams

Tasks and work order:

Study the structure of flowers, compose and write down their formulas, and for some, draw diagrams.

For analysis, take live or preserved onion flowers ( allium sp.), daylily ( Hemerocallis sp . ), peas ( Pisum sativum L . ) or domestic apple tree ( Malus domestica Borkh . ).

Consider onion or daylily flowers. Note that the flowers are regular, a simple perianth consisting of two three-membered circles, the onion is septate, and the daylily is sphenoid. The stamens also form two three-membered circles.

Special attention pay attention to the relative position of the elements of the perianth and androecium: the elements of neighboring circles alternate with each other (the stamens of the outer circle are opposite to the leaflets of the outer circle, and the stamens of the inner circle are opposite to the leaflets of the inner circle).

To count the number of carpels composing the pistil, a transverse section of the ovary is made. The pistils of onions and daylilies are formed by three fused carpels, each of which forms one nest in a three-locular ovary - the syncarpous gynoecium.

Write down the formulas and draw diagrams of onion and daylily flowers (Fig. 81, 82).

Rice. 81.General view ( A), formula ( B) and diagram ( IN) onion flower - allium sp.

rice. 82. Formula ( A) and diagram ( B) daylily flower - Hemerocallis sp .

Consider an apple tree flower. Note that the flower is regular, the perianth is double five-membered, the stamens are indefinitely large number, the pistil has five free styles and one lower ovary, fused with other parts of the flower.

Cut the ovary crosswise. The cut shows five nests - a syncarpous gynoecium of five carpels.

Write down the formula of the flower: *Ca 5 Co 5 A ¥ G (5)

Examine the pea flower (Fig. 83). Note that the flower is irregular, with a double perianth.

Draw the petals of the moth's corolla, indicate the sail (or flag), oars (or wings) and the boat. Separately, sketch the bifraternal androecium, where nine stamens of two circles have fused, forming an open stamen tube, the cut of which is covered by a wide thread of one free stamen of the outer circle. The pistil is easily removed from the flower - the upper ovary is free.

Cut the ovary crosswise. The cut shows one nest with one suture, therefore the gynoecium is monocarpous.

Write down the formula of the flower: Ca (5) Co 1,2,2 A (5+4),1 G 1,

draw a diagram of a flower.

rice. 83. Structure of a pea flower - Pisum sativum L .

Subject. Inflorescences

Flowers on the shoots of the plant are arranged singly or collected in inflorescences. An inflorescence is a collection of flowers located on axes devoid of typical leaves. Flowers collected in inflorescences are more noticeable from a distance than single small flowers, and therefore attract the attention of pollinating insects. In wind-pollinated plants, cross-pollination is ensured by a huge mass of pollen.

The classification of inflorescences is based on the methods of their growth (Fig. 84). Monopodial, or uncertain, or bothric inflorescences are characterized by the fact that their flowers bloom on axes from bottom to top. The first-order axis of such inflorescences does not stop growing for a long time; the apical flower on it opens last. There are indeterminate inflorescences simple And complex.

Simple monopodial inflorescences. Inflorescences are called simple, in which the flowers are located directly on the first-order axis (sometimes in the axils of the bracts) or on the pedicels, i.e. at the tops of the second-order axes.

simple inflorescences with an elongated axis.

brush – an inflorescence in which identical pedicels (second-order axes) sequentially extend upward from the first-order axis, bearing flowers.

Shield- an inflorescence similar to a raceme, but whose flowers have pedicels of different lengths (the lower ones are much longer than the upper ones), so all the flowers are located in the same plane. (Pýrus communis L . ) .

Ear- a derivative of the raceme, differing from it by sessile flowers - plantain (Plantago sp .), orchis (Orchis sp .) .

Earring– drooping ear, i.e. a spike with a soft axis bearing unisexual flowers; after flowering, the inflorescence usually falls off entirely - willow (Salix sp .) , poplar (Populus sp .) .

cob- a type of ear, but with a thick, fleshy axis - marsh whitewing (Calla palustris L. ) , marsh calamus (Acorus calamus L .) , anthurium (Anthúrium sp .) . Often the cob is surrounded by a leaf different shapes and coloration, which is called the veil or wing.

Simple inflorescences with a shortened axis.

Umbrella– a derivative of a raceme with a strongly shortened thin axis and flowers on pedicels of equal length – greater celandine (Chelidonium május L .) , primrose (Primula sp .) , ginseng (Panax ginseng).

Head– a modified umbel with sessile or almost sessile (with very short pedicels) flowers – clover (Trifolium sp .) , hop alfalfa (Medicago lupulina L. ) . The axis of the inflorescence is club-shaped.

Basket– close to the head. Characteristic of representatives of the Asteraceae (Asteraceae) family. The shortened axis of the basket grows in the form of a saucer or cone; tightly closed small sessile flowers are located on it.

Complex monopodial inflorescences. Inflorescences in which the second-order axes bear not individual flowers, but simple inflorescences, are called complex.

Panicle- this is a complex raceme bearing simple inflorescences different types: simple ears (spikelets) – oats ( Avena sativa L.), bluegrass ( Póa sp.), fescue ( Festúca sp.) and other cereals; baskets - wormwood ( Artemisia sp.), small petal ( Erigeron sp.) and other Compositae (Asteraceae); brush – common lilac ( Syringa vulgaris L . ), grape ( Vitis sp.).

Complex shield- bears simple inflorescences of different types on the axes of the second and third orders: corymbs - common viburnum, or red ( Viburnum opulus L.), mountain ash ( Sorbus aucuparia L.), black elderberry ( Sambúcus nigra L.); baskets – yarrow ( Achillea sp.), tansy ( Tanacetum vulgare L.).

Complex ear– bears sessile spikelets on the main axis – wheat ( Triticum sp . ), rye ( Secále cerále L.), barley ( Hordeum sp.).

Complex umbrella– on the shortened main axis there are axes of the second order, ending with simple umbrellas. Often at the base of a complex umbrella there are small leaves that form general wrapper, at the base of simple umbrellas there are leaves private wrapper (wrappers). A complex umbrella is typical for plants of the umbrella (celery) family - fragrant dill, or garden dill ( Anethum graveolens L.), carrots ( Daucus sativus(Hoffm.) Roehl.), fragrant celery ( Apium graveolens L.), curly parsley, or garden parsley ( Petroselinum crispum(Mill.) Nym.).

Earring- a pendulous inflorescence that falls off entirely after fruiting. The flowers in an earring can be arranged like a complex spike, or panicle, or other complex inflorescence (if the flowers are arranged like a simple inflorescence, then such an earring will belong to simple inflorescences).

Sympodial, or certain, or cymose inflorescences are characterized by the fact that the flower blooms first on the first-order axis, stopping its growth. Then axes of the second, third and higher orders appear successively, also ending in a flower.

Monochasium is an inflorescence in which, after the flower blooms on the first-order axis, a flower develops at the top of the second-order axis, then on the third, etc. Thus, on each axis of the previous order, only one axis of the next order is formed. Monochasium develops in plants with spiral leaf arrangement.

If all axes are directed in the same direction, then such a monochasium is called curl - comfrey (Symphytum sp. ) , borage (Borago sp.), bruise (Echium sp. ) . If the axes are sequentially directed in different sides, then monochasium is called gyrus– gladiolus ( Gladiolus sp. ) .

Dikhaziya is characterized by the fact that after the flowering of one apical flower on the first-order axis, flowers simultaneously appear on two second-order axes. The latter outgrow the first order axis. On the axes of the second order, paired axes of subsequent orders appear. False dichotomous growth - soapwort (Saponaria sp. ) , chickweed (Stellaria sp. ) .

Dichasia are formed with opposite leaf arrangement.

Pleiochasia - in this type of inflorescence, unlike dichasia, not two, but more second-order axes extend from the first-order axis from one node. This pattern persists during the further formation of the inflorescence. Pleiochasia is characteristic of milkweed (Euphorbia sp. ) .

Pleiochasia are formed with whorled leaf arrangement.

Thyrsus– a complex inflorescence with a monopodially growing main axis and sympodially growing lateral inflorescences. The degree of branching of the lateral inflorescences decreases from the base to the apex, giving the thyrsus a pyramidal shape.

Work 56 Inflorescences

Tasks and work order:

Using living plants or herbarium specimens, determine the types of inflorescences.

Examine the existing inflorescences using a textbook, determine what type they belong to, indicate the method of growth (monopodial or sympodial); simple or complex.

Draw diagrams of the inflorescences, arrange them according to the method of growth, and indicate their names. Give examples of plant species with such inflorescences.

rice. 84. Inflorescence patterns

Note: It is convenient to use to get the job done ready-made kits herbarized inflorescences, grouped by type of growth.

Definition 1

Flower- a modified shortened shoot, adapted to the formation of micro- and megaspores, gametes and cross-pollination. Plant scientists have put forward two directions. In one direction, the flower was characterized by the presence of a stamen, pistil and perianth. And on this basis it was concluded that only angiosperms have flowers. In the other direction, the characteristic of a flower is the production of spores and gametes. From the flower a seed or fruit developed. This statement proved that the flower is like angiosperms, and gymnosperms.

A flower ends with a side or main shoot. A cover flower is a flower that ends in a side shoot. The axis of the flower is called the receptacle. It can be considered the main part of a flower, since the calyx, corolla, stamens, and pistil are attached to it.

Picture 1.

The receptacle is individual for each plant. So the peon has a flat receptacle, the buttercup has a convex receptacle, the cherry and rose have a concave receptacle. In some plants you can see pedicels on the flowers; this is the part of the stem that bears the flower. If there is no peduncle, then such a flower is called sessile. On the peduncle, in turn, you can observe bracts; in each plant their number varies, or is absent altogether. This fact helps to classify plants into families, genera and species.

Calyx formed from sepals, usually green. Its function is to protect the flower when it is in the bud stage. The cups may be fused or free.

Flower petals form a corolla. Unlike the cup, it is painted in a bright color. Each plant has its own flower pigment. In nature there are a wide variety of corolla shapes and colors. If more than one axis can be drawn through the rim axis, such a rim is called regular. The regular corolla is found in plants of the cruciferous and clove families. If there is only one axis, then such a corolla is irregular; it is found in the Lamiaceae and moth families of plants. In canna and valerian it is generally impossible to draw a single axis; these are also irregular corollas. Like the calyx, the corolla can be fused or free. Because of its pigmentation, the corolla attracts insects that pollinate the plant.

Cup with whisk form a perianth. There is a double perianth, consisting of a calyx and a corolla. A simple perianth has either a calyx or a corolla. The simple corolla-shaped perianth is brightly colored. For example, in plants such as tulip, lily, peon. A simple cup-shaped corolla of green color is characteristic of plants such as nettles and beets. Also, in nature you can find flowers without perianths; they are called naked flowers. Such naked flowers are characteristic of ash, sedge, and willow.

The structure of the stamen, anther and pollen

Stamen consists of a stamen filament and an anther attached to its tip, in which spores directly develop, and from them pollen.

filament It can be narrowly cylindrical, flat, plastic or fleshy. In some plants the filament is short or does not develop at all. The filament is attached to the anther.

Anther is formed from two longitudinal halves connected to each other by a bonder. Plant species are distinguished by the shape of the anther. Thus, the anther is most often motionless in plants, but in some it sways, for example in lilies and cereals. Each half of the anther has two pollen nests, where, in turn, microspores develop and turn into pollen.

Microspores, germinating inside the anther, produce male gametophytes. Upon germination, microspores divide mitotically, forming a small reproductive cell and a large vegetative cell. The sperm develops from the reproductive cell, and the pollen tube develops from the vegetative cell.

Pistil structure

Fusing together, the carpels form a pistil. The pistil stores the seed germs, directly in the lower swollen part of the ovary. The pistil carries a stigma on which pollen enters and germinates. Column at different plants different, sometimes not developed at all. Due to the undeveloped style, the stigma is called sessile. Plants can have several pistils, and their number depends on the number of ovaries. In turn, the ovary is upper, middle and lower.

Depending on the number of nests in the ovary, single-locular, two-locular and multi-locular ovaries are distinguished. The nest contains seed buds. Their number is directly proportional to the type of plant. On the inner walls of the ovary, seed germs are laid in the form of small tubercles. The place where the embryos are formed is called the placenta. The seed germ is attached to it with the help of an achene.

The integuments of the seed germs form an opening - the micropyle. The nucellus, located under the integumentum, surrounds the embryo sac. Nucellus is the nucleus of the seed germ. At the micropylar end of the embryo sac there are three cells - one large egg and two synergids. At the opposite end there are three antipodal cells. As a result of the fusion of two polar nuclei, a secondary nucleus was formed. The secondary nucleus is located in the center of the embryo sac.

Flower formula and diagram

The flower formula is described by the following notation:

• $P$ – simple perianth,
• $K$ – calyx,
• $C$ – corolla,
• $A$ – stamen,
• $G$ – pestle.

The number of these elements is indicated by numbers. If it is impossible to count an element, put an infinity sign. If the members are fused, they are indicated by a bracket; if the elements go in a circle, they put a plus sign. The ovary is indicated by a line below or above the number, respectively, the bottom line is below, the top line is above. The wrong rim has an upward arrow, the correct one has an asterisk. A unisexual flower of the male type, i.e. staminate is designated - ♂, female pistillate - ♀ bisexual, these two signs are combined.

Examples of color formulas

Lily $P_3+3, A_3+3, G(3)$, which means regular corolla, simple perianth with $6$ petals, stamens also $6$, and $3$ fused pistils.

Ranunculus $K_5, C_5, A~, G~$, which means a regular corolla, a calyx of $5$ sepals, a corolla of $5$ petals, and an infinite number of stamens and pistils.

Rapeseed $K_2+2, C_4, A_2+2, G_2$, decipher. Regular corolla, calyx of $4$ sepals, corolla also of $4$ petals, $4$ stamens, $2$ pistils.

Definition 2

Diagram– this is the projection of the flower on a plane, perpendicular to the axis of the flower. The diagram is drawn from a cross-section of undisclosed flower buds. The diagram shows a more accurate structure of the flower than the formula.

Functions of a flower

At first glance, it seems that the function of a flower is to provide aesthetic diversity to our flora. Flowers delight our eyes with their beauty, and most of them have a refined aroma that does not leave our sense of smell indifferent. But flowers are not only about beauty and aroma. Main function Flowers for the plants themselves are reproduction. Thanks to the shape and pigments that color the flower, as well as essential oils Carrying aroma, the flower attracts the attention of insects and pollinating birds.

Note 1

Unfortunately, not all plants are colorful, fragrant and large flowers, in nature there are small, dull flowers that do not attract the attention of pollinators. Such plants are pollinated by the wind.

When pollinated in the ovary of a flower, seeds form and develop.

To briefly record the structure of a flower in botany, formulas and diagrams are used, which give a visual representation of the structure of the flower.

The flower formula is short description structure of a flower using letters, numbers and signs. Each part of it is indicated by the initial letter of the flower's name. The calyx is called Calyx (Ca), the corolla is called Corolla (Co), the set of stamens is Androeceum (A), the set of pistils is Gynoeceum (G). A simple perianth is called Perigonium and is designated in the formula by the letter P. The number of members of the individual parts of the flower is expressed by a number and is indicated in the formula as an index with right side. For example, the corolla is five-petalled - Ca5 or the androecium is six-membered - A6. If the number of flower parts is more than 12, then instead of the number they write the sign ?. In the case of fusion of flower parts, the number indicating their number is enclosed in brackets Ca(5). In the case of partial fusion of flower parts in the formula, a number in brackets is written through a plus, for example A1+(9). If the parts of the flower are arranged in circles, then the numbers indicating their number in whorls (circles) are connected by a + (plus) sign. For example, the perianth of the lily P3+3. In the formulas, you need to indicate the type of ovary by location on the receptacle (upper, lower, middle). The initial letters of the names of flower parts with indices are written in one line, for example: Ca(5)Co5A?G(5).

If the ovary is superior, then the number indicating the number of carpels is emphasized at the bottom, if the ovary is inferior, at the top. For example, G(3) or G(5) means that there is only one pistil in the flower, but it is formed by three or five carpels.

Symbols of the flower formula: * - actinomorphic flower; ^ - zygomorphic flower; > - staminate flower; + - pistillate flower. For example, the formula of cabbage flower is *Ca4Co4A2+4G(2), apple tree *Ca(5)Co5A?G(5), lily *P3+3A3+3G(3).

An even more complete picture of the structure of a flower is given by a diagram representing a projection of the flower onto a plane perpendicular to its axis. When drawing up diagrams, the following symbols are used: O - the axis of the flower, crescent-shaped arches with a keel indicate the sepals and bracts, petals are denoted by crescent-shaped arcs without a keel, stamens are a cross-section through the anther, a pistil is a ring that reflects the cross-section through the ovary (Fig. 2) .

Rice. 2. Constructing a flower diagram: 1 - flower axis; 2 - (bract) covering leaf; 3 - bracts; 4 - sepals; 5 - petals; 6 - stamen, 7 - gynoecium.

The diagram is designed so that the covering leaf is at the bottom, the axis of the inflorescence is at the top, and between them the parts of the flower are located in circles with conventional signs. When parts of a flower grow together in the diagram conventional signs connected to each other by a line.

Flower formula and diagram.

Since the 19th century. in academic work and scientific research For greater clarity, use formulas and diagrams. Flower formula - symbol its structure using letters of the Latin alphabet, symbols and numbers. When compiling the formula, the following notations are used: I am a simple perianth (perianthium); Ca(or K) - calyx (calyx); Co(or C) - corolla (corolla); A - androecium (androeceum); G- gynoecium (gynoeceum); the * sign placed at the beginning of the formula indicates the actinomorphism of the flower; sign - on its zygomorphy. A bisexual flower is indicated by a masculine sign - ♂; female - ♀. The "+" sign indicates that the parts of the flower are arranged in two or more circles, or that the parts separated by this sign are opposed to each other. The brackets mean the parts of the flower are fused together. The number next to the symbol indicates the number of members of that part of the flower; a line under the number indicating the number of carpels in the gynoecium, for example 3, indicates that the ovary is superior; the line above the number is the inferior ovary; line from the number - semi-inferior ovary. A large and indefinite number of terms is denoted by the sign ∞.

For example, the formula for a tulip flower * P 3 + 3 A 3 + 3 G (3) shows that it is actinomorphic, has a simple six-membered perianth, the free lobes of which are arranged three in two circles; the androecium is also six-membered, consisting of two circles of stamens, and the gynoecium is coenocarpous, consisting of three fused carpels (compound pistil), forming the superior ovary.

Dandelion flower formula Ca 0 Co (5) A(5) G (2) or (1) indicates that its flowers are zygomorphic, bisexual, have a perianth in which the calyx is reduced, the corolla consists of five fused petals, the androecium - of five stamens stuck together by anthers, and the gynoecium - of two fused carpels forming the inferior ovary. Since only one of the two fused carpels develops, i.e., the pseudomonocarpous gynoecium, a more rational notation for the dandelion flower formula is acceptable: G(1 ) . Formula of white jasmine flower Ca (5) Co (2+3) A 4 G (2) indicates its zygomorphy, . bisexual, double perianth, in which the calyx consists of five fused sepals, and the corolla of five fused petals, two of which are opposed to the other three; the androecium is formed by four free stamens, and the coenocaric gynoecium is formed by two fused carpels that form the superior ovary.

A flower diagram is more visual than a formula. It represents a conditional schematic projection of the parts of a flower onto a plane and reflects their number,

relative sizes and mutual arrangement, as well as the presence of accretion (Fig. 99). In addition, the diagram often indicates the location of the covering (bract) leaf, bracts and the axis of the inflorescence or shoot, carrying a flower. The bract, bracts, and sepals are most often represented by brackets with a keel (curly brackets) various sizes, petals - in round brackets, stamens in the form of a cut through the anther or, for simplicity, in the form of a shaded ellipse, genice - also in the form of a cut through the ovary or ovary (for the apocarpous gynoecium) with a drawing of the placentation site and ovules through which the cut passed.

Plants with beautiful bright flowers form the large family Asteraceae. It includes more than 32 thousand species distributed on different continents.

general description

The second name of the family is Asteraceae. Are they angiosperms or flowering plants, belonging to the class Dicotyledons.

Most of the family are herbaceous annuals or perennials. In areas with a tropical climate, shrubs (some species of the genus Brachylena) and trees (Scalesia petiolate) are found.

A characteristic feature of the plants is small flowers located at the widened end of the peduncle, forming a basket. From the outside it may seem that this is a single large flower with long petals. In fact, the core of the “flower” is formed by many small flowers 2-3 mm long. Vivid examples- sunflower, chamomile, dandelion, cornflower.

Rice. 1. Representatives of Asteraceae.

Plant structure

General characteristics of the Asteraceae family are presented in the table.

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Plant organs	Description
Root system	Rod
	Erect, hard, often branched
	Simple, entire or dissected. Location - alternate, rarely - opposite
Inflorescence	Simple - a basket. The receptacle is expanded, has a convex or concave shape. The bottom is surrounded by a wrapper. The calyx is formed by bracts in one or two rows
	Bisexual or same-sex. Has a double perianth. The calyx is absent or modified into hairs or setae. Five fused petals. The anthers of the five stamens form a dense tube around a style with a bipartite stigma. The general formula of a flower of the Asteraceae family is CH0L(5)T(5)P1, where the calyx (P), perianth (O), petals (L), stamens (T), pistils (P).
	Dry - achene. Often there are pappuses - crest, parachute, fly, hooks, spikes for better distribution

Flower morphology

The flower is the most complex part of the plant. Small flowers consist of five petals fused into a tube. Based on their shape, there are five types of fused-petalled corolla:

• tubular - original type with correct form, consisting of a tube (fused corolla) and five petals bent to the sides, often bisexual;
• funnel-shaped - a type of tubular corolla without stamens and pistils with an expanded and curved upper part;
• reed - irregular shape, consisting of a fused lower part of the corolla, and a tongue formed by five fused and bent petals, often bisexual;
• false lingual - a variety of the reed type with a reed of three fused petals, usually has only a pistil;
• bilabiate - a unisexual or bisexual variety of the reed type with two reeds formed by three and two fused petals.

Rice. 2. The structure of the Asteraceae flower.

In some representatives of the Asteraceae, the basket consists only of tubular flowers (burdock, artichoke), in others - only of reed flowers (lettuce, dandelion, chicory). In some species, for example, chamomile, tubular flowers are in the center, and reed flowers are located along the edges (white petals are elongated reeds).

Flowers of different sexes are combined in one basket. Only the edges can grow female flowers, and inside - bisexual or male. All flowers can be bisexual or only the central ones (sterile at the edges). Dioecious species are also found.

Application

Asteraceae are important in different types human activity.

• Medicine . Chamomile, yarrow, arnica, coltsfoot, tansy are used to treat gastrointestinal disorders, inflammation of the skin and respiratory tract.
• Landscape design . Because of bright look plants are used to decorate flower beds. They grow asters, dahlias, daisies, marigolds, and marigolds.
• Agriculture . Cultivated plants used for food. Oil is made from sunflower seeds, surrogate coffee is made from chicory, a sugar substitute is made from stevia, and Tarragon drink is made from tarragon. One of the types vegetable crop Asteraceae is lettuce or lettuce.