the Kingdom of plants
the Richest kingdom of flora - from bacteria to familiar to everyone plants amazes with the variety. Comprehension of its secrets conducts to understanding of that vital role which plants play our life.
Though vegetative fossils meet much less often, than animals as at plants is not present either bones, or a skeleton, however up to now cunningly many the fossil remains giving accurate representation about evolution of flora. The primitive forms of vegetation absorbing nutrients from soil and atmosphere were the first shy displays of a life on the Earth, and monocelled seaweed at which the basic vital processes occurred within one cage became the first plants deserving of this name, most likely. From them conduct the sort metaphytes at which various functions are carried out by separate parts or bodies.
Becoming the bottom link of a food chain, primitive seaweed has opened a way to fauna development. Like the majority of plants, they developed nutrients, black energy from a sunlight.
Two groups of plants
Flora traditionally divide on two basic groups: "эшч°шх" or not floral plants (seaweed, ferns and mosses) and "т№ё°шх" or floral (orchids, bushes and trees). However, internal differentiations in a kingdom of plants have any character. According to some scientists, separate kinds of live beings cannot be carried with confidence neither to flora, nor to fauna that is why it is necessary to allocate them in a separate category. Bacteria, in particular, concern it and the blue-green seaweed which cages are deprived the issued kernels.
The World of seaweed is much more various, than it seems at first sight - from the elementary monocelled to difficult metaphytes of type of sea kale. The majority of seaweed lives in water, but they are easy for finding and in any crude place on a land in the form of a greenish touch on the dampened walls or flowerpots.
The Elementary monocelled vodorosl - hlamidomonada. It receives all nutrients from water and "яыртрх=" with the help zhgutikov. Breeds by cell fission.
At higher step of development costs Spirogyra, which cages form long threads. To it we are obliged "чтх=хэшхь" standing reservoirs. This vodorosl is easy for studying under a microscope because its cylindrical cages are built in long chains, and the plant increases at length, but not at thickness. Multicellular vodorosl it is more fair to consider this as a colony of the unicells living after division in a uniform cover. Reproduction occurs or vegetative (the plant part disappears, forming a new organism), or a sexual way (at coupling of two threads there is an exchange of a cellular material, from formed zigospory the new thread grows).
In large sea seaweed it is easy to learn difficult multicellular plants though on an internal structure they are much easier than the relatives with the present stalks and leaves. In some regions of Great Britain use in food green vodorosl Viva lactuca - sea salad. In the different countries of the world other seaweed happens frequent visitors on a table also. In Saudi Arabia from an agar make raw materials for many kinds of production - from a nutrient medium for laboratory cultures to ice-cream.
At mushrooms is not present a chlorophyll helping green plants to transform a solar energy in nutrients, therefore they or eat dead fabrics, or live at the expense of other live organisms.
Some mushrooms can be seen only under a microscope. Others - are appreciable with open years. A truffle which in many countries of the world is considered a refined delicacy, too a mushroom. Mushrooms differ wide variety of forms - from bright fly agarics to not striking mould on a grain crust.
There is at mushrooms one more, rather unpleasant role - they are activators of many illnesses of plants (fitoftoroz a potato) and animal (epidermofitija stop). However, other versions serve as raw materials for valuable medicines, including the famous antibiotic of penicillin.
Many mushrooms breed by means of tiny cages, or dispute which are easily carried by a wind. Some kinds for this purpose have floccuses (threadlike vyrosty under a surface) which, merging, make a genetic material. Under favorable conditions the vegetative body which throws out disputes in environment is formed of it.
Lichens are, as a matter of fact, mushrooms living together and monocelled seaweed though the result of this symbiosis is not similar to the parents. Lichens grow there where not under force to get accustomed to other plants - on naked rocks, wood trunks or in skulls of the lost animals bleached by the sun. They meet much to the north and to the south of any other plants, and than 5600 m. grow in the Himalayas the Lichen as the result of symbiosis seaweed and a mushroom, is one of the most successful examples mutualizma, or mutually advantageous partnership at heights more.
Mosses and pechenochniki
Bryophyta (mosses and pechenochniki) are primitive land plants. Their stalks, leaves and roots are much easier on a structure, than similar parts of the higher plants. Without having wood fabrics, they are always very small, and unlike the higher colleagues have no the special cages spending water and nutrients. The majority of these plants prefers to lodge in damp shady places though many mosses are capable to maintain months a drought. At mosses and pechenochnikov difficult enough life cycle. The disputes thrown out by an adult plant sprout, forming colonies of female and man's plants (at some kinds on one plant simultaneously exist both female, and man's reproductive bodies). The formed man's cages "яюфяы№тр¦=" to female jajtsekletke by means of special zhgutikov. This phase of reproduction always occurs in the damp environment. Other type of a plant develops from impregnated jajtsekletki, or sporofita (containing disputes). Eventually, disputes are sprayed, and all cycle begins anew.
The group Pteridopbyta includes ferns, horsetails and plauny. Treelike ferns can grow till the sizes of the present tree. All these plants have stalks, root system and various leaves under the form, but they never blossom.
Ferns are the largest class plaunov which, without being mosses, are outwardly similar to them. Today they, as well as horsetails, represent small group of plants.
Most floral plants are familiar to us. The majority of agricultural, decorative cultures and trees concerns them. However, them tsvetki are frequently ordinary-looking, and golosemennyh (including coniferous trees), strictly speaking, at all you will not name floral. But all golosemennye and pokrytosemennye, i.e. Truly floral, breed seeds and with rare exception live on a land. Not for reproduction the damp environment is required to floral plants.
Golosemennye is the most ancient group of plants existing today which breed the present seeds. Secondary growth occurs at them quite normally, and, increasing year rings, sejanets in due course grows in a usual tree. To golosemennym the highest concern also in the world trees - the Californian sequoias. However tsvetki at them primitive enough, and seeds are formed in cones.
From coniferous the pine and a fur-tree are most known, but there are also other kinds living mainly in tropics. For example, sagovniki, more similar to palm trees or ferns, grow only in rainforests. Reproduction of coniferous breeds occurs to the help of pollen which is transferred by a wind with man's on pistillate flowers (cones). Fertilisation occupies long enough time From some kinds. For example, at pines passes year and more before the pollen kernel will sprout and will merge with a female cage. The ripened seeds drop out of cones and are frequently carried by birds.
Tsvetki of these plants are easily distinguished, as those, and seeds, unlike coniferous breeds, are concluded in an original case. This kind consists from odnodolnyh and dvudolnyh plants. The majority shirokolistyh floral plants concerns to dvudolnym (i.e. Two cotyledons) have. At odnodolnyh plants only one cotyledon though this distinction is shown only at germination of seeds. odnodolnye do not grow at the width, therefore all treelike plants - trees and bushes - are dvudolnymi. However some odnodolnye - for example, agaves - grow and at thickness, forming the short stalk similar to a wood trunk.
To odnodolnym to plants many grasses, cereals and some ornamental plants, for example, lilies concern.
Bacteria - the most diverse form of a vegetative life - meet in sea and fresh water, in air, soil and even a dust. They differ from other plants a number of features and the protoplasm lump, the prisoner in the strong cover consisting of fiber, instead of cellulose (as at other plants) represent. They do not contain hloroplastov, therefore only the few are capable to develop independently nutrients, and the majority is saprofity or parasites. Some float (in water or blood) by means of one or several zhgutikov, and all of them are extremely small - about 0,0001 mm in diameter.
Bacteria breed by division in two. Protoplasm is divided on two parts, everyone contains a half of an initial kernel. In 20-30 minutes new individuals ready to division grow from them, and under favorable conditions one bacterium can give all for 10 hours a life of hundreds millions microorganisms!
Some bacteria are widely used by the person. With their help make a butter and cheeses, they serve as raw materials for manufacture of many antibiotics (for example, streptomycin). The small group of bacteria causes various illnesses, especially food poisonings.