The relationship of plastic and energy metabolism.

Protection against ionizing radiation with the help of screens.

Screen- closed chamber, the requirements for which are as follows:

When operating at full power, the energy leakage should not exceed σ adm

Unit control - remote

Door interlock application (automatically relieves tension when doors are opened)

Ventilation, inspection holes, control handles must be protected from energy leakage into the environment

3. Determine at what distance from the ground electrode the voltage will not exceed 36V. A short circuit to a grounded case occurred in a network with the following parameters:

1) metabolic value: the body receiving O, nutrients for building cells and energy for life processes.

2) Metabolic functions: transport of nutrients and O from the external environment into the body, the participation of these substances in complex metabolic reactions with the absorption and release of energy, and the removal of decay products to the outside.

3) The relationship of plastic and energy metabolism: plastic metabolism supplies organic substances and enzymes for energy metabolism, and energy metabolism supplies for the plastic - energy, without which fusion reactions cannot proceed. Violation of one of the types of cellular metabolism leads to disruption of all vital processes, to the death of the organism.

1) the main features of plants of different departments.

Almost all plant organisms are capable of photosynthesis - the formation organic molecules from inorganic due to the energy of light.

Plants have specific pigments contained in plastids: chlorophyll is green, carotenoids are red, orange-yellow.

The vital processes of a plant organism are regulated by special plant hormones - phytohormones. Their interaction provides growth, development and other physiological processes occurring in plants.

Plant cells are surrounded by a thick cell wall. It is formed mainly by cellulose.

The metabolic product is cell sap, which increases intracellular pressure. As a result, plant tissues acquire high strength.

Plants are characterized by unlimited growth: they increase in size throughout their life.

2) Signs of complication of plant organization.

The emergence of multicellular algae

The appearance of stems and leaves in mosses

The appearance of roots in ferns

The appearance of angiosperms in which the seed is surrounded by a fruit or capsule

3) Reasons for evolution.

· Natural selection . The stronger and more resilient survive climatic conditions and further development of the plant

· Heredity. The ability of organisms to transfer their characteristics and properties unchanged to daughter organisms.

· Variability. The ability of organisms to acquire new traits and properties in the process individual development.

· Struggle for existence. The set of diverse relationships between living organisms and the environment.

TICKET#1

The relationship of plastic and energy metabolism.

Metabolism- the main sign of the living. The constant exchange of each living organism with the environment substances: the absorption of some substances and the release of others. Absorption by plants and some bacteria from environment not organic matter and using the energy of sunlight to create organic substances from them. Obtaining from the environment by animals, fungi, a significant group of bacteria, as well as by humans, organic substances and the energy of the Sun stored in them.

essence of exchange. The main thing in metabolism and energy conversion is the processes occurring in the cell: the entry of substances into the cell from the environment, with the help of energy their transformation and the creation (synthesis) of certain cell substances from them, then the oxidation of organic substances to inorganic substances with the release of energy. Plastic metabolism is the process of assimilation by the body of substances obtained from the environment and the accumulation of energy. Energy metabolism - oxidation in most organisms of organic substances and their breakdown to inorganic - carbon dioxide and water with energy release. The value of energy metabolism is the provision of energy for all vital processes of the body. The relationship of plastic and energy exchanges. Release of end products of metabolism (water, carbon dioxide and other compounds) into the environment.

The value of metabolism: providing the body with the substances and energy it needs to build its body, freeing it from harmful waste products. The similarity of plastic and energy metabolism in animals and humans.

Complication of the organization of plants in the process of evolution. Reasons for evolution.

Causes of plant evolution: the variability and heredity of the organism, the struggle for existence in nature and natural selection - their discovery in the middle of the 19th century by the English scientist Charles Darwin. The occurrence of changes in plants during their life, the transmission of some of them to offspring by inheritance. Preservation by natural selection of changes useful under certain conditions, their transmission to offspring in the process of reproduction. The role of natural selection, which has been going on continuously for millions of years, in the emergence of new plant species.

Stages of plant evolution. The very first most simply organized organisms are unicellular algae. The appearance of multicellular algae as a result of variability and heredity, the preservation of this beneficial feature by natural selection. The origin from ancient algae of more complex plants - psilophytes, and from them - mosses and ferns. The appearance of organs in ferns - a stem, leaves and roots, a more developed conducting system. Origin from ancient ferns due to heredity and variability, the action of natural selection of ancient gymnosperms, which produced a seed. Unlike a spore (one specialized cell from which a new plant develops), a seed is a multicellular formation, has a formed embryo with a supply of nutrients, covered with a dense peel. A significantly higher probability of a new plant from a seed than from a spore that has a small supply of nutrients. Origin from ancient gymnosperms more complex plants - angiosperms, which had a flower and a fruit. The role of the fruit is to protect the seed from adverse conditions. Distribution of fruits. The complication of the structure of plants from algae to angiosperms over many millions of years due to the ability of plants to change, to transmit changes by inheritance, the action of natural selection.

Ticket number 2

1. Respiration of organisms, its essence and significance.

1. The essence of respiration is the oxidation of organic substances in cells with the release

energy needed for life processes. Receipt of the necessary

for breathing oxygen into the cells of the body of plants and animals: in plants through

stomata, lenticels, cracks in the bark of trees; in animals - through the surface

body (for example, in an earthworm), through the respiratory organs (trachea in insects,

gills in fish, lungs in terrestrial vertebrates and humans). Oxygen transport

blood and its entry into the cells of various tissues and organs in many animals

and a person.

2. Participation of oxygen in the oxidation of organic substances

to inorganic, the release of the energy received from food,

its use in all life processes. oxygen uptake

body and remove carbon dioxide from it through the surface of the body or

respiratory organs - gas exchange.

3. The relationship between the structure and functions of the respiratory system.

The adaptability of the respiratory organs, for example, in animals and humans, to perform

functions of oxygen uptake and carbon dioxide release: volume increase

lungs of humans and mammals due to the huge number of pulmonary

bubbles penetrated by capillaries, an increase in the contact surface

blood with air, increasing the intensity of gas exchange due to this.

The adaptability of the structure of the walls of the respiratory tract to the movement of air during

inhalation and exhalation, cleansing it of dust (ciliated epithelium, the presence of cartilage).

4. Gas exchange in the lungs. Gas exchange in the body

diffusion. Entry into the lungs through the arteries of the pulmonary circulation, venous

carbon dioxide. The penetration of oxygen into the plasma of venous blood from the lungs

bubbles and capillaries by diffusion through their thin walls, and then into

erythrocytes. The formation of a fragile combination of oxygen with hemoglobin -

oxyhemoglobin. Constant saturation of blood plasma with oxygen and simultaneous

release of carbon dioxide from the blood into the air of the lungs, the transformation of venous blood

into the arterial.

5. Gas exchange in tissues. Walking in a big circle

blood circulation arterial, oxygenated and poor in carbon dioxide

blood in tissue. The supply of oxygen to the intercellular substance and cells of the body, where

its concentration is much lower than in the blood. Simultaneous blood saturation

carbon dioxide, converting it from arterial to venous. Transport

carbon dioxide, which forms an unstable bond with hemoglobin, into the lungs.

2. Kingdom of plants, their structure and activity. Role in nature and life

1. characteristics of the plant kingdom. Variety of plants: algae, mosses,

various environmental conditions. General features of plants: grow all their lives, almost

do not move from one place to another. The presence of a strong membrane in the cell

fiber that gives it shape, and vacuoles filled with cell sap.

The main feature of plants is the presence of plastids in their cells, among which

the leading role belongs to chloroplasts containing a green pigment - chlorophyll.

The mode of nutrition is autotrophic: plants independently create organic

substances from inorganic using solar energy(photosynthesis).

2. The role of plants in the biosphere. Use of solar

energy to create organic substances in the process of photosynthesis and release during

This oxygen is necessary for the respiration of all living organisms. Plants -

self-sustaining producers of organic matter, and

animals, fungi, most bacteria and human food and contained in it

energy. The role of plants in the cycle of carbon dioxide and oxygen in the atmosphere.

Complication of plants in the process of evolution, classification of angiosperms. Determine the place of the May lily of the valley species in the system flora(department, class, family, genus).

The complication of plants in the process of evolution proceeded in the following directions:

cell differentiation, the formation of tissues that differ in structure and functions: educational, integumentary, mechanical, suction, conductive, assimilation (carrying out photosynthesis);

emergence of specialized organs: shoot, including stem, leaves, generative organs, and root;

a decrease in the role of the gametophyte (haploid generation) in the life cycle and an increase in the role of the sporophyte (diploid generation);

transition to reproduction by seeds, which did not require the presence of water for fertilization;

special adaptations in angiosperms to attract pollinating insects.

The angiosperm division includes the dicotyledonous and monocotyledonous classes. AT school course the following systematic categories are studied: family, genus, species. May lily of the valley classification:

Department of angiosperms, or flowering
Monocot class
lily family
Genus lily of the valley
May lily of the valley view

3. Using knowledge of immunity, explain the purpose for which a person is vaccinated and sera are administered. How can you increase the protective properties of the body? How to protect yourself from HIV infection and AIDS?

Immunity is a protective reaction of the body to foreign bodies and substances. Immunity is natural: congenital or acquired during life.

To develop resistance to the disease, artificial immunity is formed by introducing a weakened culture of microorganisms to a person. At the same time, antibodies are produced in the body. This allows the body to successfully fight off the infection in the event of a subsequent infection. Such artificial immunity is called active. The first vaccination in history was smallpox.

If infection or penetration of poison (with a snake bite) has already occurred, a person is injected with a serum containing ready-made antibodies that help neutralize the adverse effects. Immunity resulting from the introduction of serum is called passive.

The protective properties of the body increase with hardening, physical education, proper nutrition, the content in food of a sufficient amount of vitamins. Less likely to get sick people with a balanced nervous system enthusiastic, optimistic.

AIDS (acquired immunodeficiency syndrome) is a disease that destroys the body's immune system as a result of infection with HIV (human immunodeficiency virus). HIV is transmitted through blood and sexual contact. In order not to get AIDS, one should categorically exclude drugs, casual sex from life, and not abuse alcohol, which deprives a person of the ability to control his actions. Do not allow the use of common syringes, needles, and in the hairdresser - a razor, manicure accessories that have not been disinfected (for this you need to soak in alcohol or cologne for 25 minutes).

1. Biosphere - a global ecosystem, its boundaries. Living matter biosphere. The role of man in the conservation of biodiversity.

The biosphere is the shell of the Earth inhabited by living organisms. Includes all ecosystems found on the planet. Life has been found in the deepest ocean trenches, in oil fields (anaerobic bacteria that feed on oil paraffins). The upper limit of the biosphere is limited by high ultraviolet radiation in upper layers atmosphere, the depth of habitation in the soil - the high temperature of the underlying layers of the earth's crust.

The living matter of the biosphere has a tremendous impact on all processes, participating in the processes of matter and energy circulation. Suffice it to recall the formation of oxygen reserves in the atmosphere and the ozone screen, limestone reserves in the oceans.

The stability of the communities included in the biosphere depends on their species diversity. The decline in the number of one species does not have a serious impact on the community as a whole, if the role of the retired species is "taken over" by existing existing species with similar needs. Therefore, the preservation of the entire diversity of species in ecosystems and the biosphere as a whole - biodiversity, is the main task of today in the field of nature protection. Since the significant harm caused by a person natural environment threatens the existence of many species as a result of direct extermination or destruction of habitats, coordinated purposeful activity of all states is necessary to preserve biodiversity as a guarantee of sustainable development of civilization and conservation of nature.

Monocarpic and polycarpic plants. Annuals bloom and bear fruit once in a lifetime, after which they completely die off. They behave like monocarpics - once fruiting plants. Most perennial grasses, woody and semi-woody plants are polycarpic, that is, they bear fruit many times during their lives.

But not all perennial plants are capable of repeated flowering and fruiting. Among perennial grasses and even among woody plants, there are also monocarpics, which die off entirely after the first fruiting. Unlike annuals, the vegetative phase of their life lasts several, sometimes many (50-60) years. Some types of palms can serve as typical examples ( Corypha), agaves, some types of bamboos. Perennial herbaceous monocarpics include many Compositae (for example, some types of thistles and thistles) and umbellate (angelica, angelica, cumin, caraway). These plants in the form of a rosette live 5-10-12 years, after which they bloom and die. In culture, these same plants (for example, cumin) usually behave like biennials: in the first year they go through a vegetative rosette phase, and in the second year they bloom. Biennials, including cultivated ones - cabbage, carrots, beets - are also monocarpics.

Large and small life cycle. In the course of individual development - ontogeny- Plants undergo age-related physiological changes from the embryonic state to sexually mature, and then to extreme old age. Morphologically, these age-related changes are expressed in a successive change in the structure of root and shoot systems, in the ratio of vegetative and generative organs, in the ability for vegetative propagation by certain stages ontogeny, finally, simply in the size of the body. However, it is not easy to determine the absolute age of plants, since they are characterized by a constant change of organs. Older parts die off and collapse. The age of a perennial herbaceous plant, calculated from the annual growth of the rhizome in length or from the annual rings of wood on a cross section, usually does not reflect its true age, but only corresponds to the age of the youngest living part. . An individual that has arisen sexually (from a seed) may sooner or later lose its integrity and break up into several daughter viable individuals, i.e., form a clone. Each new individual - part of a clone (particle) - bears a seal to some extent the age of the maternal seed individual, but may also be significantly rejuvenated (individuals from dormant buds of rhizomes, root offspring). Daughter individuals go through their own life cycle, starting not from the moment of seed germination, but from the moment of separation from the mother plant. In herbaceous plants that quickly change shoots, each shoot goes through a life cycle from bud deployment to flowering, fruiting and death of the aerial part (“small cycle”). Therefore, it becomes necessary to single out the concept of “long life cycle”, which means the entire ontogeny of a plant, from the emergence of an embryo in a seed to the natural death of an individual and all its vegetative descendants, i.e., parts of a clone, if vegetative reproduction takes place. A large life cycle consists of a set of small cycles of different scales (individual shoots, partial bushes, etc.). In vegetatively immobile and vegetatively inactive plants, the boundaries of the individual and the clone are more compact, in vegetatively mobile plants they are very vague, and in the later stages of a long life cycle they are often indeterminate.

Age groups of perennial polycarpic plants. Each individual at a certain moment of its development can be characterized in two ways: 1) by the calendar age, representing the length of time from the moment the individual appeared to the moment of observation; 2) a set of age characteristics that characterize the stage of ontogenetic development of an individual, its age level.

Currently, when determining the stage of ontogenetic development of an individual, the term " age condition". Synonyms for this term are "physiological age," biological age "and" age.

The age state of an individual can be defined as its physiological and biochemical state, reflecting the stage of individual development that the individual goes through at the time of observation. The idea of ​​the age state as a stage of individual development of an individual formed the basis of numerous periodizations of ontogeny.

Age-related changes are manifested in changes in both the structure (morphs) and body functions. Indicators of age-related conditions in cenopopulation studies are mainly morphological changes associated with anatomical, physiological, and biochemical changes.

The age state is always associated with the calendar age of the plant, since the sequence of ontogenetic processes proceeds in time.

The long life cycle is usually divided into the following age states (according to the classification of T.A. Rabotnov, with some changes):

1 From lat. latens- hidden, invisible.

2 From lat. virginitas- virginity.

3 From lat. juvenilis- youthful.

4 From lat. immaturus- immature.

5 From lat. senilis- senile.

This classification of age conditions applies to both polycarpics and annual and perennial monocarpics. In polycarpics, all the age conditions listed above are usually distinguished, in some cases they do not have a pronounced post-generative period (some tree species). In monocarpics, all age states are distinguished up to the generative period, the generative one is not subdivided.

The assignment of plants to one or another age state is made on the basis of a complex qualitative features. The most significant of them are the following: the mode of nutrition (connection with the seed); the presence of embryonic, juvenile or adult structures and their quantitative ratios in an individual; the ability of individuals to seed or vegetative reproduction, the ratio and intensity of these processes; the ratio of the processes of neogenesis and dying off in an individual, the degree of formation of the main features of a biomorph in an individual. "Life form", "biomorph"" is defined by adults, usually in a state of g 2 .

Seasonal phenomena in plants. One of essential features life form - the seasonal behavior of the plant. In a periodically dry or cold climate, seasonal phenomena are expressed in a number of morphological and anatomical changes. One of the most famous and conspicuous seasonal processes - leaf fall in woody plants, which is replaced "Vetkopad" in leafless xerophytes of deserts, for example, in saxaul.

In herbaceous plants, leaf fall is rarely observed (for example, in stinging nettle, impatiens). Usually, completely elongated vertical above-ground shoots die off from grasses, and on surface creeping and rosette shoots, the leaves die off and are destroyed gradually, without falling off. Dead shoots of grasses are also destroyed gradually, leaving under the snow or rising above the snow cover (in the latter case, seeds that remain until winter in fruits or seedlings, for example, in wormwood and other Compositae, continue to scatter in winter).

In spring, all perennial plants, woody and herbaceous, develop buds and grow new annual or elementary shoots. At the same time, the work of the cambium is renewed and intensified in perennial stems and roots. At the same time, reserve nutrients are actively mobilized from the parenchymal tissues of the storage organs (in particular, this causes spring sap flow in trees). During the entire growing season, perennial plants form and mature new buds of renewal, laying in them new vegetative, and often generative organs. The accumulation of reserve nutrients increases by the onset of winter or drought; specialized storage organs are formed - tubers, bulbs, etc. At the beginning of a new growing season, these substances are intensively spent on the intensive growth of new shoots and roots and the resumption of the work of the cambium. In many perennial grasses, especially meadow grasses, in addition to the spring deployment of buds, summer-autumn shoot formation is also well expressed, i.e. formation of the second generation of shoots during the growing season. In meadow grasses (fescue, bluegrass, etc.), the growth of the second generation of shoots is strongly stimulated by mowing. The so-called "otava" is used for the second mowing or grazing of livestock.

Flowering frequency. The flowering period for different plants occurs at certain times. In particular, early-flowering species should be especially noted; some of them bloom immediately after snowfall or even with a noticeable residual snow cover. Early spring flowering plants include many of the tree species and shrubs of the middle zone: alder (near Moscow blooms first, in March or early April), hazel, willow, aspen, poplar. All of them bloom before the leaves bloom, which contributes to wind pollination, and willows are pollinated by newly awakened bees. A little later, at the same time as the leaves bloom, birch, maples, elm, ash and, finally, oak, in which leaves unfold later than most other deciduous species of the mixed Central Russian forest, bloom. Early-flowering herbaceous plants are characteristic of broad-leaved forests (lungwort, corydalis, anemone, chistyak, spleen, blueberry, liverwort; they are pollinated by the first insects before shading by the tree canopy); in the forest zone in open areas, the only early-flowering species is coltsfoot. Some types of sphagnum bogs (cassandra, or marsh myrtle) bloom early. In the steppes, semi-deserts, many plants bloom early, using the spring moisture (tulips, hyacinths, bird-leavers, adonis, etc.).

The duration of flowering of different plants is also different. Some plants fade quickly, in a few days; others bloom for weeks; the third - almost the entire season, from spring to autumn, due to the appearance of new flowers and inflorescences on the same shoot (forget-me-not, cinquefoil) or new flowering shoots (soddy, buttercup). Some plants that have a limited flowering time in spring or early summer can re-bloom in the event of a long warm and humid autumn (tenacious, buttercups, strawberries, etc.).

Vegetation duration. According to the duration of vegetation (meaning the presence of green assimilating leaves), plants can be divided into evergreen(all year round with green leaves; leaves live for more than one astronomical year - conifers, lingonberries, hoof), summer-winter-green(all year round with green leaves, but individual leaves live less than a year and are replaced - acid, cuff, strawberry), summer green(deciduous or with shoots completely dying off for the winter), winter green(lose leaves or shoots for the summer, and vegetate in autumn and winter - some plants of the Mediterranean climate with severe summer drought and mild warm winters). Among the summer-greens in a broad sense, we can highlight ephemera spring, and sometimes autumn (annual plants vegetating for a very short time - from 2-3 weeks to 1-2 months), and ephemeroids (perennials that lose the entire above-ground part very quickly, by the beginning of summer, are desert and steppe tulips, tuberous and bulbous forest ephemeroids - corydalis, anemones).

The diversity of plants in terms of vegetation and flowering in the same community contributes to the most complete use of the entire growing season as a whole, i.e. different groups are adapted to different, seasonally changing lighting conditions (the establishment and disappearance of shading by a canopy of trees in a deciduous forest), humidity, temperature, to different pollination factors, etc.

Adaptations of higher plants to heterotrophic nutrition. For higher plants, autotrophic nutrition is usually and normally - photosynthesis in combination with soil nutrition, which supplies the plant with all the necessary mineral elements, including nitrogen. The method of nutrition is reflected in the general appearance of the higher plant with its developed system of leafy green shoots and the root system intensively spreading in the soil. Real heterotrophic organisms that can feed on dead organic residues (saprotrophs) are found only among fungi and bacteria. However, higher plants also have a number of adaptations to the use of not only mineral, but also organic substances of the substrate. This is especially important in the conditions of the almost complete absence of mineral salts, for example, with an epiphytic lifestyle or when living on very poor leached soils, on sphagnum peat bogs. In most cases, flowering plants living on such substrates, while remaining green and capable of photosynthesis, receive additional nitrogen nutrition due to symbiosis with fungi or bacteria that settle in their roots (mycorrhiza, bacteriorhiza). This is - symbiotrophic plants.

Some autotrophic plants that usually live in swamps (in the tropical and partly temperate zone) make up for the lack of nitrogen in the substrate with additional nutrition from small animals, in particular insects, whose bodies are digested with the help of enzymes secreted by special glands on the leaves. insectivores, or predatory, plants. Usually the ability to this type of food is accompanied by the formation of a variety of hunting devices.

In a sundew common in sphagnum swamps, the leaves are covered with reddish glandular hairs, which secrete droplets of a sticky, shiny secretion at the tips. Small insects stick to the leaf and with their movements irritate other glandular hairs of the leaf, which slowly bend towards it and tightly surround it with their glands. Dissolution and absorption of food occur within a few days, after which the hairs straighten out and the leaf can again catch prey.

The trapping apparatus of the Venus flytrap living in the peat bogs of the east North America, has a complex structure . The leaves have sensitive bristles that cause a sharp slamming of the two lobes of the blade when touched by an insect.

Trapping leaves in Nepenthes , climbing plants of coastal tropical thickets of the Indo-Malay region, have a long petiole, the lower part of which is wide, lamellar, green (photosynthetic); the middle one is narrowed, stem-like, curly (it wraps around the support), and the upper one is turned into a motley jug, covered with a lid on top - a leaf blade. A sugary liquid is released along the edge of the jug, which attracts insects. Once in the jug, the insect slides along the smooth inner wall to its bottom, where the digesting liquid is located.

In stagnant water bodies, we usually have a submerged floating pemphigus plant. It has no roots; the leaves are dissected into narrow filiform segments, at the ends of which there are trapping vesicles with a valve that opens inward. Small insects or crustaceans cannot get out of the bubble and are digested there.

The emergence of unicellular and multicellular algae, the emergence of photosynthesis: the emergence of plants on land (psilophytes, mosses, ferns, gymnosperms, angiosperms).

The development of the plant world took place in 2 stages and is associated with the appearance of lower and higher plants. According to the new taxonomy, algae are classified as lower (and earlier they were classified as bacteria, fungi and lichens. Now they are separated into independent kingdoms), and mosses, ferns, gymnosperms and angiosperms are classified as higher.

In the evolution of lower organisms, 2 periods are distinguished, which differ significantly from each other in the organization of the cell. During 1 period, organisms similar to bacteria and blue-green algae dominated. The cells of these life forms did not have typical organelles (mitochondria, chloroplasts, Golgi apparatus, etc.). The cell nucleus was not limited by the nuclear membrane (this is a prokaryotic type cellular organization). The 2nd period was associated with the transition of lower plants (algae) to an autotrophic type of nutrition and with the formation of a cell with all typical organelles (this is a eukaryotic type of cellular organization, which was preserved at subsequent stages in the development of the plant and animal world). This period can be called the period of dominance of green algae, unicellular, colonial and multicellular. The simplest of the multicellular are filamentous algae (ulotrix), which do not have any branching of their body. Their body is a long chain of individual cells. Other multicellular algae are dissected by a large number of outgrowths, so their body branches (in hara, in fucus).

Multicellular algae, due to their autotrophic (photosynthetic) activity, have evolved in the direction of increasing the body surface for better absorption of nutrients from aquatic environment and solar energy. Algae have a more progressive form of reproduction - sexual reproduction, in which the beginning of a new generation is given by a diploid (2n) zygote, combining the heredity of 2 parental forms.

2 evolutionary stage of plant development must be associated with their gradual transition from water image life to the ground. The primary terrestrial organisms were psilophytes, which were preserved as fossils in the Silurian and Devonian deposits. The structure of these plants is more complex compared to algae: a) they had special organs for attaching to the substrate - rhizoids; b) stem-like organs with wood surrounded by bast; c) rudiments of conductive tissues; d) epidermis with stomata.

Starting with psilophytes, it is necessary to trace 2 lines of evolution of higher plants, one of which is represented by bryophytes, and the second by ferns, gymnosperms and angiosperms.

The main thing that characterizes bryophytes is the predominance of the gametophyte over the sporophyte in the cycle of their individual development. A gametophyte is a whole green plant capable of self-feeding. The sporophyte is represented by a box (cuckoo flax) and is completely dependent on the gametophyte for its nutrition. The dominance of the moisture-loving gametophyte in mosses under the conditions of the air-ground lifestyle turned out to be inappropriate, therefore, mosses have become a special branch of the evolution of higher plants and have not yet produced perfect groups of plants. This was also facilitated by the fact that the gametophyte, in comparison with the sporophyte, had a dinner heredity (haploid (1n) set of chromosomes). This line in the evolution of higher plants is called gametophyte.

The second line of evolution on the way from psilophytes to angiosperms is sporophytic, because in ferns, gymnosperms and angiosperms, the sporophyte dominates in the cycle of individual plant development. It is a plant with a root, stem, leaves, organs of sporulation (in ferns) or fruiting (in angiosperms). Sporophyte cells have a diploid set of chromosomes, because they develop from a diploid zygote. The gametophyte is greatly reduced and adapted only for the formation of male and female germ cells. In flowering plants, the female gametophyte is represented by the embryo sac, which contains the egg. The male gametophyte is formed by the germination of pollen. It consists of one vegetative and one generative cell. When pollen germinates from a generative cell, 2 sperm are produced. These 2 male germ cells are involved in double fertilization in angiosperms. A fertilized egg gives rise to a new generation of plants - the sporophyte. The progress of angiosperms is due to the improvement of the reproduction function.