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secondary, more than twice) and a haploid nucleus is formed from the division of the added
nucleus (from the Greek, haplos divided) will be In the cell of eukaryotes, soda performs the
task
of moving along the undulipod, which is located with the help of special bodies
(kinetosome).
Plant nutrition
: The world of plants is divided into genoforms and autotrophs
depending on their nutrition. According to modern scientists, the oldest form of nutrition is
heterotrophic nutrition.
The body of the initially formed heterotrophic nutrition is complex. It did not have cell
parts like those of modern organisms. A simple cell is fed by ready-made organic matter. Such
nutrition is called saprophytic (Greek
sapros - humus, trophic nutrition). All animals, fungi,
single-celled organisms, bacteria and some algae are saprophytes. Currently, most scientists
recommend that fungi be separated from the plant world, because they do not have motile
cells during their life. However, given some of the characteristics of fungi:
non-stop cell
growth, reproduction, and their similarity to bottom plants, they are studied by transplanting
them into plants. The evolution of fungi begins with unicellular eukaryotes. Most
representatives of fungi are mainly saprophytes and feed on decaying organic matter. They
break down organic substances, exchange substances in nature,
and ecological balanceis an
important biological catalyst in storage. In the process of decomposition, organic matter
releases atmospheric carbon dioxide gas and supplies the soil with nitrogenous compounds.
Nutrition of higher plants with the participation of fungi is called mycotrophic (Greek-mycos-
fungus) nutrition. Parasites (Greek: parazitos-tekinkhur) are also found among heterotrophic
feeding plants and fungi.
They live at the expense of plants and animals. For example,
among flowering plants,
sedge, ivy, sedge; Among the fungi, black moth and rust fungi belong to free-parasitic feeders.
Among the plants, there is also a mixed myxotrophic (from the Greek mixis - mixed) nutrition.
Such organisms, in addition to the organic matter produced by photosynthesis, also feed on
ready-made organic matter. Such a phenomenon can be found in euglena, a representative of
green algae. In a slow and long process of evolution, the first photosynthetic autotrophic (self-
feeding) organisms appeared on Earth about 3.4 billion years ago. The origin of life on Earth
depends on autotrophic organisms. The cells of early autotrophic organisms were simpler
compared to modern autotrophs but more complex compared to heterotrophs. The cell of
autotrophic plants contains the pigment chlorophyll (chromatophore), which gives it a green
color. All green plants that have chlorophyll or chromatophore in
their cells absorb carbon
dioxide from the air, and in the process of assimilation, they obtain the energy needed to form
organic matter from inorganic substances from sunlight.
Part of the oxygen released due to the process of photosynthesis turns into azone (03) in
the atmosphere, and it does not send the ultraviolet rays released from sunlight to the earth. It
allows living organisms to develop here. In addition, the plant breathes from the amount of
oxygen it releases. There are other types of autotrophic organisms that live underground in
total darkness. Such organisms are called chemotrophic organisms. Chemotrophic organisms
get the energy they need for food. This is called chemosynthesis. Chemosynthesis was first
introduced in science by the Russian scientist S.N. Discovered by Vinogradsly (1887).
Chemotrophic
plants include iron, sulfur bacteria, and nitrogen-fixing bacteria.