Psulifitis - the firstborn of terrestrial vegetation. Transitional form
It is of undoubted interest to get acquainted with a relatively recently open science of the firstborn of the ground flora.
They were called plyphithi. Fossil remains of them in late silicular sediments and especially the first half of Devon, covering the period of time at about 20-30 million years, are quite numerous and diverse.
These were small plants relatively simple appearance. Their body, like algae, was not disseminated on the usual major organs for higher plants. They had no roots. The most simple of the pylofitis also did not have the stems in the usual understanding of the organ carrying the leaves, since they did not have leaves.
The earliest among psulifitis and the most simple to dismember the body are rinia and khornaya. Indeed, they are so easy to build that many algae look much more complex. They have an underground part, similar to the rhizome, from which vertically standing, Wilechato branching steplain-like organs. Instead of the roots, these plants are formed only unicellular growths on "rhizomes" - rhizoids, similar to root hairs on the roots in flower plants. At the ends of the branches are located sporangies. They developed controversy, with which the psiliefs multiplied. Riland and Horney were small plants height from 20 to 40 cm. They lived on the swamps.
Larger plant was psulofitonHe reached a height of up to 1.5-2 m and had a richly branching overhead part of the body. It had grown in the form of spikes. In the underground "rhizomes", multicellular growth has also developed.
Even more difficult dismemberment reached asteroxille. The most important difference of this plant is that its above-ground organs are thickly covered with scratched outgrowths, similar to small leaves, but differing from real leaves, the absence of veins. Internally, instead of the rhizoids, the branches are reduced into the depths of the soils, which can be viewed as root root. In the wall, the asteroxylon sporangium has already been so characteristic of the ring of cells with thickened walls so characteristic of many currently living ferns. Thanks to this ring, when ripening, the sporal wall is broken and the disputes were released.
With the outer simplicity of the dismemberment of the ppilifitis body, the internal (anatomical) structure was quite complicated.
Examine the details of the anatomical structure in petrified remnants of plants, as we said, it is possible to do so thin sections of these fossils, which can be studied under a microscope as sections with living plants, and see individual cells that make up certain tissues.
In the center of their rhizube-like and sterep-like organs, a real wood has already appeared, consisting of water-conductive cells (tracheid). Wood is surrounded by a lob from elongated cells, according to which organic substances generated by the plant were moved. From the surface, the body is dressed in typical skin (epidermis). Among the cells, the skin is found typical of the highest plants, through which gas exchange was carried out. Everything makes it impossible to assume that the pylofitis of the gas exchange occurred in the same way as in modern plants: carbon dioxide carbon dioxide flowed from the atmosphere from the atmosphere, and the oxygen is already accumulated in the atmosphere, necessary for breathing, and from the body of the plant were highlighted in The atmosphere of water pairs, carbon dioxide formed in the process of respiration, and oxygen released from the water in the process of photosynthesis. Sporangia has a thick wall, well-defending tender in young dispute.
According to geology, land on Earth in the described time (in the Devonian era) was represented by two major continents: the equatorial, located from modern South America through Africa to Australia, and the North, stretching from the North Atlantic outskirts through Greenland to Central Europe. There were still large islands to the east and west of the northern mainland. In the coastal sediments of this sushi and the plants described by us were buried. Many of them were still closely connected with the aquatic environment and were swamp plants, in which only the upper part of the body rose above the surface of the water. But among the pylofitis there were real land representatives of larger sizes - up to 3 m in height.
Based on knowledge of the changes occurring on our planet at certain stages of its history, and on the basis of the restoration of the appearance of the cultivation of the Earth in their fossil residues, it is possible to draw a picture of land landscapes in the respective period.
The ancestors of pylofitis, according to general recognition, are algae. Which of the familiar types of algae, psilofitis spawned, is definitely difficult to say. Rather, it was green algae, since the green color of the above-ground organs is characterized for the entire ground vegetation. But the difference even between the simplest of psulifitis and any algae representative is very large.
On the way from algae to psulifitis, life made a huge step forward. To take at least the presence of psychochitis in psulietics with a complex method of expanding or narrowing the slot between the cluster by the cells. Or the presence of ppyloffs of wood associated with the appearance of a new chemical in nature lignincausing an adhesion of the cell wall. Finally, it should be borne in mind that it is hardly psulphites could settle right on the mother breeds, and not on the soil. Soil, as you know, is created thanks to the activities of organisms. Therefore, it is natural to assume that the pylofs were not the first avant-garde of settlers on land, but the forms that conclude the chain of organisms are even simpler and closer to the lower plants - algae. It should be assumed that the inhabitants of the reservoirs and not only algae moved to the land, but with them other organisms - mushrooms, bacteria, possibly the simplest animals. They lived in moistened places, forming peculiar groups in which the role of the breadwinner belonged, naturally, algae and autotrophic bacteria. There could be a close cohabitation between autotrophic and heterotrophic organisms, for example, between algae and mushrooms, at which that and the other cohabiter received benefits: the fungus mined water from the soil, the algae delivered organic matter.
It is interesting to note that phenomena has a phenomenon of cohabitation (symbiosis) with mushrooms: threads of mushrooms were found in the cells of the underground organs, i.e., already at the dawn of ground existence in the plant world were mycarishes - "Mribocornis", which received the widest distribution The stories of ground flora.
The vital activity of the lower organisms and could lead to the creation of primary soils on the place of mother breeds. Soil-forming processes, according to the teachings of Academician V. R. Williams, played and play a huge role in changing plant formations. Inhabited, though in a humid, but still ground medium, algae was exposed to this much more volatile medium. These changes, mainly the drying of the soil, naturally, had to cause corresponding reactions of organisms and determine changes from the organisms themselves. There were changes in both biochemical processes and morphological structures. The chain of such aimed change and led to the fact that organisms appeared on the arena of life, to some extent adapted to existence on land, psulphites. But among them there is no uniformity of the forms: some of them still stand with "legs in water", the other fully went to the land.
Geological chronicle has not yet been read. Just about 30 years ago, psilofitis were discovered and studied, and this radically changed the former ideas about the origins of the ground flora. Perhaps in more ancient layers there will be ground predecessors of pylofitis, and this will further expand our horizons. But it is not necessary to close the eyes and that most of the people who have ever lived, especially those gentle as algae and mushrooms, could not be preserved in the fossil state, and their traces are lost forever. Therefore, we remain the path of indirect evidence of a particular side in the development of the organic world, we have already spoken on the first pages.
Among the fossil residues of psulifitis, there are absolute traces of the genital organs, and nevertheless, we say with confidence that the plylofitis had a sexual process that they had a controversy in their dispute, on which genitals arose, and after fertilization, the body was developed psulifitis. The outline, you need to think, was small and built of thin-walled cells, so it was not preserved. Why do we so confidently talk about what no one has seen? Because the disputes of ppils preserved in the petrified state in their peculiarities are similar to the disputes of fern, for whom it is well known that they are from disputes first grows up with the genital organs on it.
So, in now living ferns from the dispute grows a small (2-4 mm in diameter) green, plate caller of the heart-shaped form. This will be the outflow. On the underside of it facing the soil, rhizoids develop. The genitals are formed here: female, called archeganis, and men - Aniardia. Sperm, emerging from Anteridy, penetrate the neck of Archeganiyev to the eggs and fertilize them. From the fertilized egg, the embryo is first developed, from it - the seedlings, and the plant itself is formed from the seedlock - fern. On the leaves (vyai) of the fern, sporangies collected by pile. In the sporangies, as we know, disputes develop. Such a cycle of development is characteristic of all fern, and psofields that begin the line of fern in the history of the plant world are not an exception to this rule.
The monograph is devoted to considering the problem of origin and the evolution of moss-shaped and unique dual development plants in the botanist. The development of this problem is a logical modeling using the cognition of the comparative morphological method as a leading tool. Based on the analysis of materials related to the organization of moscellular to the organ level, taking into account the existing ideas on the indicated problem, the author developed a holistic conceptual model of origin and the evolution of moss, ranging from the ancient ancestors Archegoniat. Particular attention is paid to Anto-Ceretian and Takakiyev as ancient land plants, a kind of "live fossil" - key taxa for the knowledge of the original stage of the evolution of embryofitis.
Designed for a wide range of specialists in the field of botany, ecology, geography, students and teachers of universities of the biological profile and all those interested in the issues of the evolution of higher plants.
Algae as an ancestor forms of archegano.
Due to the fact that briefites show much greater similarity with tracheophytes than with algae, possessing actually all the main signs of higher plants, first of all, should affect the possible ways of origin of the latter as a whole as a new level of organization in the development of the plant world.
The emergence of higher plants (archegoniath, or embryophytes) marked an important stage of the progressive, progressive development of plants, their output on a fundamentally new ecological arena, the development of a much more complex, complex ground medium, a bright manifestation of a living matter spreading on the planet, "everydayness" of life (by successful expression V. I. Vernadsky, 1960). From here, it seems obvious that the evolution of organisms is inherently adapticogenesis.
In the development of the problem of origin of higher plants, versatile research is important as various groups of higher plants and algae, which are considered as an ancestors of the Archegoniat.
To date, significant success is achieved in the study of algae, including their modern and fossil forms. In particular, the attention of the work of K. D. Stewart, K. R. Mattox (1975, 1977, 1978), K. J. Niklas (1976), L. E. Graham (1984, 1985), Yu. E. Petrova (1986) and others.
CONTENT
Preface
Methodology of research of evolution
Evolutionary theory
Modern state of evolutionary teaching
Presentations on the basic laws of evolution
The origin of higher plants
Algae as an ancestor forms Archegoniat
Change of nuclear phases (cycle of development of higher plants)
Apomixis and his role in the evolution of higher plants. The concept of "generation" against embryophytes
Possible cytological definiteness of the acestral forms of higher plants
Predecessors of higher plants and their transformation into primary archegoniats
Environmental situation when leaving the land of the initial forms of higher plants
The occurrence of embryindy
Transformation of chloroplasts in the event of higher plants
The oldest land plants. Transition forms between algae and higher plants. Rynofiti
Ways of transformation of early land plants
The origin and evolution of the main groups of moss
Anthocerotophyta (Anthocerotophyta)
The uniqueness of the organization of the group as the cause of the uncertainty of its phylogenetic position and genetic ties
Fossil plants showing traits of similarity with Anthocerotov, and their comparative analysis
Antezral form Anthoxerotovs
Features analogue of anthurserotovy with other higher plants and adapticogenesis of this group of briefites
Liver (marchantiophyta)
Ancient fossil forms of liver
Liver howrs as "the least ground" organisms among briefites
The initial environmental conditionality of liver
Historical relationships of leafy and layer morphotypes of Gametophyte
Changing the structure of the sportsman in the Nizhny Middle Devon
Latevonian-early Hammetic Evolution of Hammetophyte
Protonma (seedlings), its importance in the development cycle and transformation
Transformation of the structure of the sportsman in the Upper Devon
The evolution of liver in Carbon
Source Morphothype Gametophyte Mocho
Symmetry in the morphogenesis of liverons due to their lifestyle
Divergence of the Pechechnoshnikov department
Signs of organizing ferns as a means of knowledge of the development of briefites
Features of the organization of Jungerniyev, Jungermanniophytina
Organization of Marshantiyeviytina (marchantiophytina) as a result
their specific ecology. Group divergence
Oil calves and their dislocation in the liver
Taxons with mixed signs of two main groups of liver and model of origin of these groups
The time of the appearance of modern families and childbirth of the liver
The newest classification of liver
Mossi (Bryophyta)
Specificity of the Group's organization
Ancient fossil MAY.
The nature of the connection of moss and liver
The greatest "the degree of ground" Mukhov among briefites
Restoration of the process of formation of the main morphotype of moss
Comparative morphological series of spores as a model of their change during the evolution of Mukhov
Takakiyus (Takakiophytina)
Actually Mossi (Bryophytina)
SFAGNOPSIDA (SPHAGNOPSIDA)
Andrei Mai (AndreaEOPSIDA)
LNDRODOPSIDA (AndreaEoobryopsida)
Brown Mossi (Bryopsida)
Changes in the main number of chromosomes in moss in the process of their evolution
Brofitis in Paleocene and Eocene
The effect of climate change on briefs in oligocene and neogen
Briefites in the setting of powerful stress anthropogen
Environmental inversion Brofitov
The forecast of the evolution of briefites in connection with natural and anthropogenic changes in the biosphere
Phylogenetic relationship between the largest blue-shaped taxa, as well as between moss and other higher plants
Conclusion
Overview of the Evolution of Bryophytes According TO The Conceptual Model Suggesed by US (Summary)
Literature.
a) Only invertebrates were found in the most ancient layers.
b) than younger the reservoir, the closer the remnants to modern species.
c) with the help of paleontological finds it was possible to establish phylogenetic rows and transitional forms.
2. Fossil transients - Forms of organisms combining signs of more ancient and young forms.
a) Zverlybled reptiles are found on the Northern Dvina (genus foreigners). Had similarities with mammals in the structure of the following organs: skull; spine; limbs located not on the sides of the body, like reptile, but under the torso, like in mammals; teeth differentiated on fangs, cutters and indigenous.
b) Archeopteryix- Transitional shape between birds and reptiles, found in the layers of the Jurassic period (150 million years ago).
· Signs of birds: the hind limbs with the set, wings and feathers, the external similarity.
· Signs of reptiles: a long tail consisting of vertebrae; Abdominal ribs; the presence of teeth; claws on the front limb.
· I flew badly for the following reasons: Breet was without keel, i.e. Breast muscles were weak; The spine and the ribs were not a tough support, like birds.
in) Psulifi- Transitional shape between algae and terrestrial plants.
· The green algae occurred.
· The highest disputes of vascular plants occurred from psulifitis - planes, chests, ferns.
· Appeared in the silver, and spread in Devon.
· Differences from algae and higher disputes: psulifitis - grassy and rustic plants growing along the shores of the seas; had a branched stem with scales; The skin had a dust; Underground stem resembled rhizomes with rhizoid; The stem was differentiated on conducting, coating and mechanical fabrics.
3. Phylogenetic rows - Rows of some forms that consistently replaced each other during evolution (phylogenesis).
a) V.O. Kovalevsky restored the evolution of a horse, building her phylogenetic row.
· Ahogipus, who lived in Paleogen, was the size of a fox, had a four-panel front limb and a three-panel rear. The teeth were the tubed (sign of omnipiness).
· In neogene, the climate has become more arid, vegetation has changed, the aegipus has evolved through a number of forms: an Agippus, Merigipus, Hipparion, a modern horse.
· Signs of the aoipus changed: legs lengthened; Claw turned into hoofs; The surface of the support decreased, so the number of fingers decreased to one; The quick run led to the hardening of the spine; The transition to coarse feed led to the formation of folded teeth.
2. Comparative morphological - learns the form and structure of individual organs and their evolutionary changes. Systems of contemporary organisms form a number of consecutive changes. For example, in modern organisms, you can trace the fate of individual bones of the brain and visceral skull. Comparative-morphological evidence is close to relatively biochemical. For example, in modern organisms, you can trace the change in the structure of hemoglobin. However, there are gaps in these ranks, because not all transitional forms have been survived to our time
1. Cellular structure Organisms showed the unity of origin of the organic world.
a) organisms of different kingdoms consist of cells.
b) All cells have a similar structure of the structure.
2. Common vertebrate structure.
a) double-sided symmetry.
b) similar body cavities.
c) the presence of spine and skull.
d) a similar nervous system.
e) two pairs of limbs.
3. Homology - similarity of the bodies in structure and origin, regardless of their function.
a) The skeleton of the limbs in different classes of vertebrates is homologous.
b) Mustache pea, cacti barrels and barbaris needles are homologous to the leaves.
c) rhizomes, tubers and bulbs are homologous to stalk (these are underground shoots).
4. Analogy - similarities of organs performing homogeneous functions, but not having a similar plan of structure and origin.
a) The analogy does not play roles when establishing kinship between the species.
b) Examples:
· Butterfly wings are similar to the wings of birds and bat;
· Cancers and fish gills;
· Cactus barrels (leaves), hawthorn (shoots), roses and raspberries (skin grows).
5. Rudiment - Organs that have lost initial importance in the process of evolution to preserve the species and in the stage of disappearance.
a) Examples:
· A good lizard of the squirritian has a rudimentary shoulder limb blast, cetacean - rudimentary pelvic singing;
· In the birds on the wing of the 1st and 3rd fingers rudimentary (stylized bones);
on the rhizomes of plants there are scales - rudiments of leaves.
· In the edge flowers of sunflower there are rudimentary stamens and pestles.
b) Rudimia prove the lack of feasibility of signs.
c) Rudimia testify to the historical development of the world.
6. Atavisms- Cases of return from individual individuals to the signs of ancestors.
a) Examples:
· Three pairs of nipples in cows;
· Multi-piece in humans;
· Zebro-shaped painting foals.
b) The genes responsible for these signs are preserved, but for various reasons do not manifest.
c) Atavisms are evidence of the evolution of animals and plants.
7. Transitional forms Connect in their structure signs of lower and higher classes.
a) Examples:
· The lower mammals (waterproof and echidna) have features similar to the signs of reptiles: (cloaca, egg laying);
· The subverse of the hormone lizards (genus foreigners) is a transitional form between reptiles and mammals (fossil).
b) Using transitional forms, you can construct phylogenetic series, showing the history of the development of the form.
3. Comparative Embryology - embryology is learning the embryonic development of the body. In the course of embryonic development, embryos often observe similarities with embodies of ancestral forms. For example, in all vertebrates in the early stages of development appear inland gills (or their primitives - gill pockets).
The similarity of the embryos.
a) the building of the chordic embryo consistently resembles the body of animals of other types:
· Egg - simplest;
· Gastraul - shepherd;
· Round worms;
· Representatives of the subtype are undecented.
b) This testifies to the generality of the origin of all chord.
Origin and evolution of land plants
In the proteinous sushi was populated by prokaryotm, single-cell eukaryotes joined them later (about 1 billion years ago). The first inhabitants of the sushi were probably cyano and actinobacteria. The heterotrophic actinobacteria form numerous branching structures similar to the mushroom mycelium. They are able to unite with phototrophic cyanobacteriums in amazing symbiotic "superhorganisms" (so-called actinolishens).
Perhaps the most important evolutionary event in plywood was the development of sushi with multicellular eukaryotes. As a result, the landscapes familiar to us arose, in which land plants, insects and four-legged animals (tetrapeods) prevail.
Phylogenetic reconstructions based on the comparison of the genomes of modern organisms indicate that terrestrial plants occurred from chasing algae. Representatives of this group of freshwater green algae are both unicellular and multicellular forms. Apparently, one of the transitions to multicellity about 1 billion years ago occurred during the evolution of Harov algae. At the moment, fossil remains of transitional forms between land plants and their aqueous ancestors are unknown.
The main problems that make up aquatic plants when leaving the land and solve them. Drying (solution - coating fabrics or analized anabiosis in mugh-like), the need for gas exchange and evaporation (Ustian), absorption of substances (suction tissues, mineralization), transport of substances (conductive tissues - except mugh), competition, gravity (mechanical tissue).
Among the first inhabitants of the sushi were mushrooms that also entered into symbiosis with cyanobacteria. Genetic and biochemical systems that have developed in land mushrooms for symbiosis with cyanobacteriums later came in handy for "establishing relationships" with the first terrestrial plants. All this terrestrial microbiota gradually prepared the soil (in the literal and figurative sense) to settle sushi by plants. Ground plants from the very beginning lived in close symbiosis with soil mushrooms, without which they were most likely not able to leave their native aquatic element.
The most ancient fossils terrestrial plants are the controversy fragments of the liver moss (about 460 million years ago). According to phylogenetic reconstruction, this group of moss is the most ancient land plants. Vascular plants (all terrestrial, except for moss) arose during evolution no later than 420 million years ago. Within this group, two evolutionary lines are distinguished. Spore plants (horships, planes and ferns, no later than 350 million years ago) and sporophyte, and Gametofit - independent organisms. In seed plants, the haploid gametophyte lost its independence. The first to go to the landing spore plants (rhinofitis) - it happened at the end of the silica. They grew on coastal shallow water, they did not have real roots, special filamentine processes were served to attach to the substrate.
By the end of the Devonian period began to occur the first forests. They consisted of dispute plants - fern, planes, horsages. In Carbon (coal period) Significant warming and climate moistening provided widespread rainforest (Europe, North America, South Asia - then these territories were located in an equatorial belt) formed by tree ferns, giant tree-like horses and plauns (up to 40 m high). These forests located in the seaside lowlands do not have modern analogues. These were shallow reservoirs, crowded with organic residues. The root systems of the trees were located below the peat-like organic mass, and the trunks germinated through it and the thick layer of the chest. It was on the site of these "forest-reservoirs", large coal pools were subsequently emerged.
On the territory of modern Siberia and the Far East, which was then located near the northern polar circle, the basis of vegetation was coniferous trees with a height of up to 20 m (Cordate). Their wood has clear annual rings confirming the existence of a seasonal climate there (something like modern taiga). The territories of modern South America and Africa (their southern half), India and Australia were not far from the southern polar circle. Fall forests from ginkgy prevailed.
In Carbon, appeared and the first gone plants (The team under the name "Seed ferns"). Their seed was covered with a shell protected from drying. Reproduction with the help of seeds made a process of reproduction independent of the aquatic environment. This aromorphosis has given the opportunity to further develop sushi, promoting plants deep into the mainland.
In a colder and dry Perm period, the voted plants were widespread. From them, until today, there were few - Gingko, Araucaria, and ingotives.
Ancient reliable findings of coated (flowering) plants have age 140-130 million years old, these are single pollen grains found in Israel. The earliest macroscopic fossil remains (leaves, flowers, fruits) covered bridges are about 125 million years old. Since they are already quite diverse, apparently, the covered bridges arose much earlier (from the vicered they separated no later than 300 million years ago). Compared to gamped plants, the coated brimmed occurred, an important aromorphosis occurred - a double fertilization appeared, which made it possible to prevent in vain waste of nutrients (endosperm develops only with the embryo), the marking performs a protective function. The evolutionary success of coated plants is explained by the abbreviated life cycle, a tendency to the insect and the formation of various herbaceous forms. Some of the coated brimmed plants that have arisen in the chalk period have arisen to this day are palm trees and plane.
Now hundreds of thousands of flowers of flowering plants live on Earth, and phylogenetic relations between them are quite well studied. An important role in the appearance of a modern diversity of flowering plants was played by their joint evolution with insects.
Multicolve animals and land plants - two single known cases of incomewho led to the appearance of complex major organisms. Interestingly, the genetic mechanisms of these two independent events are very similar. First, the emergence of a complex multicellular organism was not accompanied by a significant increase in the number of gene coding genes. Instead, the interactions between genes and their regulatory elements are complicated - special DNA sequences. Secondly, animals and plants have independently arising special genes that regulate the individual development of the body.
The occurrence of single-celled and multicellular algae, the occurrence of photosynthesis: plant output on land (pliphydrates, mosses, ferns, viced, coated).
The development of the plant world was committed in 2 stages and is associated with the advent of lower and higher plants. According to the new systematics, the lower are algae (and they used to relate bacteria, mushrooms and lichens. Now they are highlighted in independent kingdoms), and to the highest - mosses, fern, voted and coated.
In the evolution of lower organisms, 2 periods are distinguished, significantly different cellular organization. For 1 period, organisms similar to bacteria and blue-green algae dominated. The cells of these life forms did not have typical organoids (mitochondria, chloroplasts, the Goljei apparatus, etc.). The core of the cell was not limited to a nuclear membrane (this is a prokaryotic type of cell organization). 2 The period was associated with the transition of lower plants (algae) to the autotrophic type of nutrition and to form a cell with all typical organoids (this is a eukaryotic type of cell organization, which has been preserved and at the next levels of the development of the plant and animal world). This period can be called a period of domination of green algae, single-cellular, colonial and multicellular. The simplest of the multicellular are nichly algae (Ullitrix), which have no branching of their body. Their body is a long chain consisting of individual cells. Other multicellular algae are dissected by a large number of outgrowths, therefore their body branches (Hara, Fukus).
Multicoloting algae due to their auto-flow (photosynthetic) activities developed in the direction of increasing body surface for better absorption of nutrients from an aqueous medium and solar energy. Algae had a more progressive form of reproduction - sexual reproduction, in which the beginning of the new generation gives diploid (2N) zygote, combining the heredity of 2 parental forms.
2 The evolutionary stage of plant development must be associated with a gradual transition to them from a water lifestyle to ground. The primary ground organisms were psiliefs that were preserved in the form of fossil residues in the Silurian and Devonian sediments. The structure of these plants is more complicated compared to algae: a) they had special attachment bodies to the substrate - rhizoid; b) stroke-shaped organs with wood surrounded by a lob; c) primitive tissue; d) epidermis with allocations.
Starting with pylofitis, it is necessary to trace 2 lines of the evolution of higher plants, one of which is represented by moss, and the second - fern, voted and coated.
The main thing is that characterizes the mugh-like, this is the predominance of the cycle of their individual development of GaMetophyte over sporophyte. Gametofit is an all green plant capable of independent meals. Spiritophyte is represented by a box (Cukushkin Len) and completely depends on its nutrition from Gametophyte. The dominance of the moisture-lifted gametophyte moss in the conditions of an air-terrestrial lifestyle turned out to be non-meter-shaped, so the MAs have become a special branch of the evolution of higher plants and have not yet been given after themselves perfect groups of plants. This was also facilitated by the fact that the Gametofit compared to the sporophyt had dining heredity (Haploid (1N) chromosome set). This line in the evolution of higher plants is called Gametophite.
The second line of evolution on the way from piclofitis to the coated bridge is sporing, because the fern, voted and coated in the cycle of individual development of plants dominates sporeophyte. It is a plant with a root, stem, leaves, spioning organs (in ferns) or fruiting (at coated). Sporophyt cells have a diploid set of chromosomes, because They develop from diploid zygota. Gametophyte is strongly reduced and adapted only for the formation of male and female sex cells. In the flowering plants, the female gamethophytic is represented by an embryonic bag in which the egg is located. Male gametophytic is formed during the proposal of pollen. It consists of one vegetative and one generative cells. In germination, pollen from the generative cell occurs 2 sperm. These 2 men's sex cells are involved in double fertilization of coated. The fertilized egg gives the beginning of a new generation of the plant - sporophyte. The progress of the coated bridge is due to the improvement of the reproduction function.
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Conclusions:
1. The study of the geological past of the land, the structure and composition of the core and all the shells, flights of spacecraft to the moon, Venus, the study of stars bringing a person to the knowledge of the stages of development of our planet and life on it.2. The evolution process was natural.
3. The vegetation world is diverse, this diversity is the result of its development for a long time. The cause of its development is not a divine force - and the change and complication of the structure of plants under the influence of the changing environment of habitat.
Scientific evidence: plant cellular structure, start of development from one fertilized cell, the need for water for life processes, finding fingerprints of various plants, the presence of "living" fossils, extinct some species and the formation of new ones.