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GENERAL CONCEPTS OF PLANT EVOLUTION AND THEIR STRUCTURE DAUGHTER
Ismailova Saida Ulug‘bek qizi,
QMU student
Abstract:
If I give a general understanding of the evolution of plants and their structure,
since the 50s of the last century, a number of scientists have been working on the evolution of
plants, and by introducing their concepts into science, they have made the evolutionary
system of plants much clearer. enriched with limes.
Keywords:
Prokaryotes, eukaryotes, cyanobacteria, nucleoplasm, genoform,
heterotroph, autotroph, histone, diploid, haploid
Abstract:
Since the 50s
of the last century, several scientists (De Fries, G. Curtis, C.
Geoffrey, E. Dotson, A. Takhtadjyan, etc.) proposed to divide the organic world into four to
nine worlds. The famous scientist academician Artur Takhtagjyan created the current system
of evolution in his work published in 1973. This system is as follows:
1. The large world of prokaryotes - organisms without a nucleus.
This large world
consists of only one small world - Procaryota, and is divided into three sub-worlds:
archaebacteria, true and oxyphytobacteria. is called The cell of prokaryotes is from 2-3
μ
m to
10
μ
m
2. Organisms that have a true nucleus are eukaryotes. This world is divided into three
sub-worlds: animals, fungi and plants. Prokaryotic plants include bacteria (protozoa) and
blue-green algae.
In some literature, blue-green algae mixed with bacteria become
cyanobacteria. Their cytoplasm does not have a clearly visible nucleus. A cell contains only
one or more pieces of DNA (deoxyribonucleic acid), called the nucleoplasm. There are no true
chromosomes, the gene that carries the hereditary traits is called a genoform.
The genoform is located around the DNA.
Protein material, mitochondria and plastids
are not found in the cytoplasm. In the cell of prokaryotic plants, there are mesosomes formed
in the cytological membrane. In addition, there
is a gas vacuole in the cell, which helps the
body to stay suspended in water. In the cytoplasm, ribosome, oil droplets, polysaccharide and
polyphosphate granules are found. The cell wall of prokaryotes does not contain chitin or
cellulose. Mitosis and meiosis of the cell and the sexual process were not determined in them.
Cell division occurs in a normal-amiotic manner.
In most representatives, the cell is born
without a cell, if it is very simple. Most representatives of prokaryotes are heterotrophs, some
representatives feed on autotrophs. Some representatives (bacteria-protozoa) are parasites.
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