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Science and innovation of the republic of uzbekistan urgench state university
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| bet | 2/13 | | Sana | 16.05.2024 | | Hajmi | 1,48 Mb. | | #237391 |
Bog'liq Structure and function of biological membranes.Purpose of the topic: Study of the structure of the biological membrane.
- function of biological membranes.
- Synthesis of membrane proteins
- Solving the structure of membrane proteins.
The task of the topic: Biological membranes are the site of many molecular systems that give rise to a variety of physiologically important functions. Among these functions are nutrient and ion transport, oxidative and photosynthetic phosphorylation, signal transduction, and electrical excitability. The cell membrane, also called the plasma membrane, is found in all cells and separates the interior of the cell from the outside environment. The cell membrane consists of a lipid bilayer that is semipermeable. The cell membrane regulates the transport of materials entering and exiting the cell.
I Chapter. Literature review
Plant physiology first appeared and developed as a branch of botany dealing with the problem of plant nutrition from the soil. Attempts to solve the problems of how plants create tissues and organs due to substances are connected with the experiments of the Dutch naturalist scientist Jan van Gelmont (1629). He plants a willow branch in a special container filled with soil of a certain weight and pours water for 5 years. At the end of the experiment, the weight of the willow branch increased 30 times, while the weight of the soil changed very little. Based on Gelmont's experiment, scientists come to the conclusion that the plant's food source is not soil, but water.
Despite the fact that such a conclusion is incorrect, the use of a quantitative method (weighing) once in the conducted experiment was of great importance in the development of further research. In 1727, the English scientist S. Gales determined the movement of water and mineral substances through plant tissues. The English scientist D. Priestley determined that the air is cleaned, animals live, and combustion occurs due to the life activity of green plants. This process was later called "photosynthesis". The works of the French scientist A. Lavoisier on combustion and oxidation (1774-84) also gained great importance in the development of plant physiology. At the beginning of the 19th century, research on plant growth and soil depletion was rapidly developing. According to the theory of humus developed by the German scientist A. Thayer, substances in the soil are of decisive importance in the nutrition of plants. In the 40s of the 19th century, the theory of mineral nutrition of the German chemist J. Liebig appeared instead of the theory of humus, which explains the nutrition of plants. According to this theory, mineral elements are of decisive importance in the nutrition of plants from the soil. Libix's research pioneered the use of mineral fertilizers in agricultural practice. In the second half of the 19th century, K. A. Timiryazev conducted important research in the field of photosynthesis and revealed the importance of chlorophyll in this process. In the second half of the 19th century and the beginning of the 20th century, a number of discoveries were made in the study of substance and energy metabolism in plants. From this period, the connection between the physiology and biochemistry of plants was further strengthened.
The achievements of plant physiology in the 20th century are related to research on plant resistance, mineral nutrition, transport of substances through plants, mechanisms of flowering, biotechnology of plant cells and tissues, etc. One of the most important discoveries in plant physiology is the identification of subtle mechanisms of energy metabolism control in green plants. Thanks to this discovery, it was shown that photosynthesis and respiration are two sides of a single process consisting of the exchange of substances and energy.
Significant progress was also made in researching the nature, physical and chemical properties, formation, metabolism and functions of photosynthetic pigments. As a result of the study of pigments, several types of photophosphorylation (cyclic, noncyclic and pseudocyclic), the mechanism of the first stages of absorption of light quanta, chlorophyll biosynthesis, stages of photosynthesis reactions that do not require light, and biochemical mechanisms were determined. By studying the individual development (ontogeny) of the plant organism and its nature, it was revealed that phytohormones present in the tissues - auxin, gibberellin, cytokinins - have a strong influence on the development of plants along with the external environment. The discovery of these substances allowed a new interpretation of the transition period of growth and development from the vegetative phase to the generative phase of plants.
In addition to growth-accelerating substances, growth-slowing (inhibiting) compounds were also identified. In the 2nd half of the 20th century, it was proved that phytochromes participate in the control of physiological processes, that they act as inducers in the biosynthesis of enzymes involved in the formation of chlorophyll, and that they are important in the formation of chloroplasts and the photosynthetic apparatus in general. Also, a number of substances similar to phytochromes, which participate in the control of phototropism and photoperiodism reactions, were discovered. As a result of the study of root rotting activity, it is determined that organic compounds (amino acids, nucleotides, vitamins, phytohormones) are synthesized in plant tissues from mineral elements absorbed from the soil. The structure and function of cell membranes, the processes related to absorption of substances, transfer and separation of ions through them; the physiological nature of the processes related to the resistance of plants to various abiotic and biotic conditions (high and low temperature, drought, high humidity, salinity, disease and insect damage) was determined.
The creation of special devices - phytotrons - was of great importance to the development of plant physiology. Such works made it possible to solve important issues such as plant acclimatization, introduction, hybridization, obtaining heterosis, placement of varieties according to regions, various agrotechnical measures: fertilization, artificial irrigation.
The development of plant physiology in Uzbekistan is associated with the establishment of the Turkestan Cotton Plant and the Turkestan University. Research conducted by A.Imomaliyev, N.Nazarov, A.Kasimov, M.Valikhonov, Kh.Salimov, R.Azimov and others was of great importance in the development of plant physiology. Great progress has been made in the study of cotton physiology in the republic.
Physiological processes during seed storage, germination, ripening were studied in detail (Kh.Kh. Yenileyev, M. Valikhonov); mineral nutrition of cotton (T. Pirokhunov), water exchange in cotton (H. Samiyev); Important studies were conducted on soil salinity and infection resistance (R.Azimov, M.Avazkhanov), cotton leaf shedding (A.Imomaliyev), the influence of external factors on the growth and development of cotton (M.V.Muhammadjonov, N.Nazarov, A.Qasimov, etc.) .
V. Zimmerman divides the types of higher plants into equal-spored and seeded ones and shows their occurrence in geological periods by percentage. P. Goryaninov (1795-1865) adds a great story to the systematics of plants in Russia. In 1894, in his book "Specific Aspects of the Natural System", he states that development in nature goes from simple to complex, and that higher plants originate from lower plants. P. Goryaninov divides the world of plants into 12 classes, 48 tribes and 187 families. The services of M. Gorajanin, N. Kuznetsov (1914), H. Gallir (1912), A. Vaga, D. Zerov, CH. Bessi (1995), D. J. Hutchinson, and N. Bush were invaluable in creating the phylogenetic system.
A. Krankvist, R. Dahlgren (1880), A. L. Takhtadjian (1987) also created a number of scientific works dedicated to the phylogenetic system. In collaboration with A.L. Takhtadjian, A. Krankvist and V. Simmerman (1966), he divides higher plants into the following sections.
Rhyniophyta, 2. Bryophyta, 3. Psilophyta, 4. Lycopodiophyta, 5. Equisetophyta, 6. Polypodiophyta, 7. Pinophyta, 8. Magnoliophyta.
In 1941, the well-known botanist A.L. Takhtadjian recommended to treat the current psilophytes as psilotes and to name it as an independent section. Currently, it consists of 9 sections in the style of tall plants.
1. Rhyniophyta, 2. Zosterophyta, 3. Bryophyta, 4. Lycopodiophyta, 5. Psilotophyta, 6. Equisetophyta, 7. Polypodiophyta, 8. Pinophyta, 9. Magnoliophyta.
Botanists in Uzbekistan such as M.G.Popov, P.Korovin, I.I.Granitov, K.Z.Zokirov also made a worthy contribution to the development of the science of systematics. A great achievement of Uzbek scientists was that they published a 10-volume Central Asian plant identifier. Currently, systematists of Uzbekistan are working on publishing the flora of Uzbekistan in Uzbek.
K.Z.Zokirov (1903-1992) "Plants of the Zarafshan River Basin" (2 volumes), Acad. Y.P. Korovin, "Plant cover of Central Asia and South Kazakhstan" (2 volumes), prof. I.I. Granitov "Plant cover of Western-Southern Kyzylkum" (2 roofs), prof. M.M.Arifkhonova made a great contribution to the development of botany in Central Asia with her works entitled "Plants of the Fergana Valley" (2 volumes).
The famous botanist P.A. Baranov (1882-1962) taught the science of plant anatomy and embryology in Uzbekistan, Acad. JK Saidov (1909-1999) made a significant contribution to the development of the science of anatomy, morphology and physiology of plants.
S.S. Authored by Sahobiddinov, the first volume published in 1957 was devoted to spore and open-seeded plants, and the second volume (1966) to higher plants. This manual was one of the first books written and published in Uzbek. It appeared at a time when botanical terminology was not yet developed.
The study of natural plants in the territory of Central Asia has been started since ancient times. We can find information about the plants of Central Asia, including modern Uzbekistan, in the works of our famous scientists who lived several hundred years ago. For example, Abu Rayhan Beruni (973-1048) in his book "Kitab al-Saydana fit-tibb" dedicated to medicine, gave information about many medicinal plants growing in our country. Abu Ali ibn Sina (980-1037) in his works "Laws of Medicine" and "Kitab ush-shifa" clearly described many medicinal plants growing in Central Asia and fully demonstrated their healing properties.
Mahmud Kashgari, who lived in the 9th century, gave valuable information about about 200 types of plants found in the territory of ancient Turkestan in the book "Devonu Lugatit Turk". One of our famous scientists is Acad. K.Z.Zokirov (1903-1992) "Plants of the Zarafshan River Basin" (2 volumes), Acad. Y.P. Korovin, "Plant cover of Central Asia and South Kazakhstan" (2 volumes), prof. I.I. Granitov "Plant cover of Western-Southern Kyzylkum" (2 roofs), prof. M.M.Arifkhonova made a great contribution to the development of botany in Central Asia with her works entitled "Plants of the Fergana Valley" (2 volumes).
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