“Structure and functions of the cell” - Cell nuclei. Shell. Microscope. Cellular center. Core shell. Cell structure. Scientist. Cytoplasm. Lysosomes. Chromosomes. Core. Mitochondria. Organoid. Cell types. How to see and study a cell. Ribosome. Golgi complex. Electron microscope. Nuclear juice. Cytoskeleton. Endoplasmic reticulum.

“Composition of a living cell” - Structure and nucleus of the cell. Lysosomes. Methods for studying cells. History of the development of the doctrine of the cell. Golgi apparatus. Kernel functions. Ribosomes. Chromosomes. Plastids. Outer cytoplasmic membrane. Organelles of movement. Types of endoplasmic reticulum. Organelles are structures that are constantly present in a cell. Mitochondria. Endoplasmic reticulum of the ER. Eukaryotic cell. Cytoskeleton. Nuclear juice. Karyolemma.

“Non-membrane organelles” - Non-membrane organelles. Structure of the cell center. Ribosome assembly diagram. Cellular center. Different types of euglena. Ultramicroscopic structure of the flagellum. Ribosomes. The structure of flagella and cilia. Organization of the cell center. Centrioles. Organelles of movement. The structure of the centriole.

“Structure of an organism cell” - Cell nucleus. Mitochondria. Cell division. The importance of ATP in metabolism. Ribosome. Energy metabolism in the cell. Cell structure. Cellular center. Nucleolus. Endoplasmic reticulum. Golgi apparatus. Lysosome. Metabolism. Plastids. Cell theory. The importance of cell organelles. Transformation of energy in the cell.

"Membrane" - Laboratory research. Consolidation. Structure. Differences. Model of membrane structure. Membrane functions. Charged molecules. Glycoprotein. Exocytosis. Similarity. Compare prokaryotic cells with eukaryotic cells. Eukaryotic cell. Plasmolysis in Elodea leaf. Cell organelles. Macrophage work. Diffusion. Let's work in the laboratory. Microscopic structure of cells. Lesson terminology. Facilitated diffusion.

“Structure of eukaryotes and prokaryotes” - The meaning of bacteria. Cytoplasm. Habitat. Prokaryotes. Compare eukaryotic and prokaryotic cells. Bacteria. Ability for active movement. Survival of prokaryotes. Heterotrophs. History of discovery. Number of bacteria. Cell structure. Organoid. Diverse ways to eat. The role of bacteria in nature. Simplicity of structure. Mitochondria. Genetic material. Differences in the structure of eukaryotic and prokaryotic cells.

Prokaryotes and eukaryotes. There are two types of cells known in modern and fossil organisms: prokaryotic and eukaryotic. These cells differ so greatly in their structural features that two superkingdoms have been identified - prokaryotes (prenuclear) and eukaryotes (true nuclear). Intermediate forms between these largest living taxa are still unknown. The main difference between a prokaryotic cell and a eukaryotic cell is that their DNA is not organized into chromosomes and is not surrounded by a nuclear envelope. Eukaryotic cells are much more complex. Their DNA, bound to protein, is organized into chromosomes, which are located in a special formation, essentially the largest organelle of the cell - the nucleus. In addition, the extranuclear active content of such a cell is divided into separate compartments using the endoplasmic reticulum. EPS is formed by the simplest membrane. Eukaryotic cells are usually larger than prokaryotic cells.

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Cell

“Mitosis cell division” - Prophase Metaphase Anaphase Telophase. Metaphase. Anaphase. Interphase. DNA helixation occurs in the nucleus; The nucleoli disappear. Formation of the spindle, shortening of chromosomes, formation of the equatorial plate. Then mitosis (cell division) occurs and the cycle repeats. Mitosis disorders. Telophase.

“Cell of an organism” - The prokaryotic type of cellular organization preceded the eukaryotic type of cellular organization. 1. Introduction. Hypothesis. What explains the diversity of cell structure types? 3 Comparison of plant and animal cells. Working group: Kobets V., Dedova A., Fokina A., Nechaev S., Tsvetkov V., Datskevich Yu.

"Cell within a body" - The cells of most single-celled organisms contain all the parts of eukaryotic cells. Microscopes were constantly improved. Classification of cells. Cells of multicellular animals. Somatic cells Sex cells. Control questions. What components does a cell consist of? What cells do you know?

“Cell division” - Meiosis Greek “meiosis” - reduction. Late prophase. Mitosis. Mitotic cycle. Chromosomes are concentrated at opposite poles of the cell. Mitosis Greek "mitos" - thread. Biological meaning. Types of cell division. Somatic. Anaphase. Metaphase. Amitosis. Telophase. Early prophase. Genitals.

“Meiosis” - Gametes with a haploid set arise from initial cells with a diploid set of chromosomes. Spermatogenesis. The second division of meiosis leads to the formation of second-order haploid spermatocytes. First division of meiosis. The basis of reproduction and individual development of organisms is the process of cell division.

Lesson topic: “Differences in the structure of eukaryotic and prokaryotic cells”

Goals: Systematize knowledge about the structure and functions of the components and organelles of a eukaryotic cell.

Test your ability to compare different cell types.

Identify the main differences between prokaryotes and eukaryotes.

Foster curiosity, independence, and respect for each other.

Lesson type : combined

Equipment : Textbook “Biology” A.A. Kamensky, E.A. Kriksunov, V.V. Beekeeper.; multimedia projector; screen; tables “Structure of a eukaryotic cell”, “Structure of a prokaryotic cell”, “Protozoan cells”.

Didactic material: presentation on the topic “Carbon”, cards with tasks, a set of individual tasks for homework.

Literature : Textbook “Biology” A.A. Kamensky, E.A. Kriksunov, V.V. Beekeeper

Lesson plan.

I Class Organization

1. Greetings

I I Communicating the topic and objectives of the lesson

I I I Checking homework

1. Frontal survey
2. Card tasks.
3. Working with the table “Comparative characteristics of the structure of eukaryotic cells”

I V Learning new material

1. Name the representatives of prokaryotes and their habitat
2. Features of respiration of prokaryotes
3. Reproduction of prokaryotes
4. Features of the structure of a prokaryotic cell
5. Comparison of eukaryotic and prokaryotic cell

   1. Endoplasmic reticulum - synthesizes and accumulates various substances in its cisterns, and also participates in their intracellular transport. 2. Cytoskeleton - determines the shape of the cell, ensures the movement of cellular organelles, ensures the movement of the entire cell 3. Cell center - forms the spindle of division in fungal and animal cells, lies at the base of flagella and cilia 4. lysosomes are single-membrane organelles that participate in cellular digestion 5. Golgi complex is the place of formation of lysosomes 6. Mitochondria are the energy center of the cell, a double-membrane cell organelle, the outer membrane is smooth, the inner one forms cristae outgrowths 7. ribosomes - carry out protein synthesis 8. Plastids - double-membrane organelles, characteristic only of plant cells, carry out photosynthesis

   Characteristics Cells of protozoan fungi, plants, animals Cell wall Large vacuole Chloroplasts Centrioles Reserve carbohydrate Method of nutrition

   1.Name the representatives of prokaryotes and their habitat 2.Features of respiration of prokaryotes 3.Reproduction of prokaryotes 4.Features of the structure of a prokaryotic cell

   Habitat Water Air Soil Living organisms Bacterial cells under a microscope Bacterial colonies in a Petri dish

   Peculiarities of respiration According to the method of respiration, bacteria are divided into two groups: 1. Aerobes - they use oxygen for respiration. 2. Anaerobes - do not use oxygen for respiration.

   Reproduction They reproduce asexually, namely by cell division. Under favorable conditions, division occurs every 20-30 minutes.

   Features of the structure of a prokaryotic cell

   Compare eukaryotic and prokaryotic cells. What differences do you see in the structure of these cells? Eukaryotic cell Prokaryotic cell

   Indeed, in a prokaryotic cell there are no: 1. Formed nucleus 2. Plastids 3. EPS 4. Mitochondria 5. Golgi complex

   Homework: Tables “Main differences between prokaryotes and eukaryotes”, §2.7

   
   

   consider the structural features and functions of non-membrane and double-membrane organelles.

   
   
   

   Characteristics of bacteria

   Distributed everywhere: in water, soil, air, living organisms. They are found both in the deepest ocean basins and on the highest mountain peak on Earth - Everest, both in the ice of the Arctic and Antarctica, and in hot springs. In the soil they penetrate to a depth of 4 km or more, bacterial spores in the atmosphere are found at altitudes of up to 20 km, and the hydrosphere generally has no boundaries for the habitat of these organisms.

   Bacteria are able to settle on almost any organic or inorganic substrate.

   Despite the simplicity of their structure, they have a high degree of adaptability to a wide variety of environmental conditions. This is possible due to the ability of bacteria to quickly change generations. With a sharp change in living conditions, mutant forms quickly appear among bacteria that are capable of existing in new environmental conditions.

   
   

   Sizes from 1 to 15 microns. Based on the shape of the cells, they are distinguished: spherical - cocci:

   micrococci- divided in different planes, lying singly;

   diplococci

   tetracocci

   streptococci -

   staphylococci -

   sarcins -

   • diplococci- divide in one plane, form pairs; tetracocci- divided in two planes, forming tetrads; streptococci - divided in one plane, forming chains; staphylococci - divide in different planes, form clusters resembling bunches of grapes; sarcins - are divided in three planes, forming packs of 8 individuals.
   
   

   Elongated - bacilli(rod-shaped) - divided in different planes, lying singly;

   Twisted – vibrios(as a comma); spirilla- have from 4 to 6 turns; spirochetes- long and thin crimped forms with the number of turns from 6 to 15.

   In addition to the main ones, other, very diverse, forms of bacterial cells are found in nature.

   
   
   

   Cell wall

   The bacterial cell is enclosed in a dense, rigid cell wall, which accounts for 5 to 50% of the dry mass of the cell.

   The cell wall serves as the outer barrier of the cell, establishing contact between the microorganism and the environment.

   The main component of the bacterial cell wall is the polysaccharide murein. Based on murein content, all bacteria are divided into two groups: gram-positive and gram-negative.

   
   

   Many bacteria have a mucous matrix - a capsule - located on top of the cell wall. Capsules are formed by polysaccharides. Sometimes the capsule contains polypeptides. As a rule, the capsule performs a protective function, protecting the cell from the effects of unfavorable environmental factors. In addition, it can facilitate attachment to the substrate and participate in locomotion.

   
   

   The cytoplasmic membrane regulates the flow of nutrients into the cell and the release of metabolic products to the outside.

   Typically, the growth rate of the cytoplasmic membrane is faster than the growth rate of the cell wall. This leads to the fact that the membrane often forms numerous invaginations (invaginations) of various shapes - mesosomes .

   
   

   Mesosomes associated with the nucleoid play a role in DNA replication and subsequent chromosome segregation.

   Perhaps mesosomes ensure the division of the cell into separate separate compartments, thereby creating favorable conditions for the occurrence of enzymatic processes.

   
   

   In the cells of photosynthetic bacteria there are intracytoplasmic membrane formations - chromatophores, ensuring the occurrence of bacterial photosynthesis.

   
   

   Bacteria are characterized by 70 S ribosomes, formed by two subunits: 30 S and 50 S. Ribosomes of bacterial cells are assembled into polysomes formed by dozens of ribosomes.

   
   

   Bacterial cells can have a variety of cytoplasmic inclusions - gas vacuoles, vesicles containing bacteriochlorophyll, polysaccharides, sulfur deposits and others.

   Nucleoid. Bacteria do not have a structurally formed nucleus. The genetic apparatus of bacteria is called nucleoid. It is a DNA molecule concentrated in a limited space of the cytoplasm.

   
   

   The DNA molecule has a typical structure. It consists of two polynucleotide chains forming a double helix. Unlike eukaryotes, DNA has a circular structure rather than a linear structure.

   The DNA molecule of bacteria is identified with one chromosome of eukaryotes. But if in eukaryotes DNA is associated with proteins in the chromosomes, then in bacteria DNA does not form complexes with proteins.

   Bacterial DNA is anchored on the cytoplasmic membrane in the mesosome region.

   
   

   The cells of many bacteria have non-chromosomal genetic elements - plasmids. They are small circular DNA molecules that can replicate independently of chromosomal DNA. Among them there are F -factor- a plasmid that controls the sexual process.

   Flagella. Among bacteria there are many mobile forms. Flagella play a major role in locomotion.

   Bacterial flagella are only superficially similar to eukaryotic flagella, but their structure is different. They have a smaller diameter and are not surrounded by a cytoplasmic membrane. The flagellum filament consists of 3-11 helically twisted fibrils formed by the protein flagellin.

   
   
   

   At the base there is a hook and paired disks connecting the thread to the cytoplasmic membrane and cell wall. The flagella move, rotating in the membrane. The number and location of flagella on the cell surface may vary.

   Fimbriae- These are thin thread-like structures on the surface of bacterial cells, which are short straight hollow cylinders formed by the protein pilin. Thanks to fimbriae, bacteria can attach to the substrate or adhere to each other. Special fimbriae - genital fimbriae, or F -drank- ensure the exchange of genetic material between cells.

   
   

   Physiology of bacteria. Nutrition

   Eating methods

   Heterotrophs

   Autotrophs

   Saprotrophs

   Photoautotrophs

   Chemoautotrophs

   Symbionts

   Physiology of bacteria. Nutrition

   Nutrition of bacteria.

   Together with food, bacteria, like other organisms, receive energy for vital processes and building material for the synthesis of cellular structures.

   Among the bacteria there are:

   heterotrophs consuming finished organic matter. They can be:

   saprotrophs, that is, feed on dead organic matter;

   Physiology of bacteria. Nutrition

   Another group autotrophs, is capable of synthesizing organic substances from inorganic ones. Among them are:

   photoautotrophs, chemoautotrophs

   • photoautotrophs, synthesizing organic substances using light energy, and chemoautotrophs, synthesizing organic substances due to the chemical energy of oxidation of inorganic substances: sulfur, hydrogen sulfide, ammonia, etc. These include nitrifying bacteria, iron bacteria, hydrogen bacteria, etc.

   Photoautotrophs:

   Photosynthetic sulfur bacteria (green and purple) They have photosystem-1 and do not release oxygen during photosynthesis; the hydrogen donor is H 2 S:

   6СО 2 + 12H 2 S → WITH 6 N 12 ABOUT 6 + 12 S + 6H 2 ABOUT

   In cyanobacteria (blue-green) Photosystem-2 appeared and during photosynthesis oxygen is released, the hydrogen donor for the synthesis of organic matter is H 2 O:

   6СО 2 + 12H 2 ABOUT → WITH 6 N 12 ABOUT 6 + 6O 2 + 6H 2 ABOUT

   
   

   Physiology of bacteria

   Chemoautotrophs :

   Chemosynthetics oxidize ammonia (nitrifying bacteria), hydrogen sulfide, sulfur, hydrogen and iron compounds. The source of hydrogen for the reduction of carbon dioxide is water. Discovered in 1887 by S.N. Vinogradsky.

   The most important group of chemosynthetics is nitrifying bacteria , capable of oxidizing ammonia formed during the decay of organic residues, first to nitrous and then to nitric acid:

   2 N.H. 3 + 3O 2 = 2HNO 2 + 2H 2 O+663 kJ

   2H N ABOUT 2 + O 2 = 2HNO 3 + 142 kJ

   Nitric acid, reacting with mineral compounds in the soil, forms nitrates, which are well absorbed by plants.

   
   

   Physiology of bacteria

   Chemoautotrophs:

   Colorless sulfur bacteria oxidize hydrogen sulfide and accumulate sulfur in their cells:

   2H 2 S + O 2 = 2H 2 O+2 S + 272 kJ

   With a lack of hydrogen sulfide, bacteria further oxidize sulfur to sulfuric acid:

   2 S + 3О 2 + 2H 2 O = 2H 2 S ABOUT 4 + 636 kJ

   Iron bacteria oxidize divalent iron to trivalent:

   4 FeCO 3 + O 2 +H 2 O = 4Fe(OH) 3 + 4CO 2 + 324 kJ

   Hydrogen bacteria use the energy released during the oxidation of molecular hydrogen:

   2H 2 + O 2 = 2H 2 O + 235 kJ

   
   

   Physiology of bacteria. Reproduction

   Bacteria are capable of intensive reproduction. There is no sexual reproduction in bacteria; only asexual reproduction is known. Some bacteria, under favorable conditions, are able to divide every 20 minutes.

   Asexual reproduction

   Asexual reproduction is the main way bacteria reproduce. It can be carried out by binary fission and budding.

   Most bacteria reproduce by binary equal transverse cell division. In this case, two identical daughter cells are formed. DNA replication occurs before division.

   Budding. Some bacteria reproduce by budding. In this case, a short outgrowth is formed at one of the poles of the mother cell - hypha, at the end of which a bud is formed, one of the divided nucleoids passes into it. The bud grows, turning into a daughter cell, and is separated from the mother cell as a result of the formation of a septum between the bud and the hypha.

   
   
   

   The sexual process, or genetic recombination.

   There is no sexual reproduction, but the sexual process is known. Gametes are not formed in bacteria, there is no cell fusion, but the most important event of the sexual process occurs - the exchange of genetic information. This process is called genetic recombination. Part of the DNA (less often all) is transferred by the donor cell to the recipient cell and replaces part of the DNA of the recipient cell. The resulting DNA is called recombinant. It contains genes from both parent cells.

   There are three methods of genetic recombination: conjugation, transduction, transformation;

   Conjugation- This is the direct transfer of a piece of DNA from one cell to another during direct contact of cells with each other. The donor cell forms what is called an F-pilus, its formation is controlled by a special plasmid - F-plasmid. During conjugation, DNA is transferred in only one direction (from donor to recipient), there is no reverse transfer.

   
   

   Transduction is the transfer of DNA fragments from one bacterium to another using bacteriophages.

   
   

   The importance of bacteria

   Bacteria play a huge role in both the biosphere and human life. Bacteria take part in many biological processes, especially in the circulation of substances in nature. Significance for the biosphere:

   Putrefactive bacteria destroy nitrogen-containing organic compounds of non-living organisms, turning them into humus.

   Mineralizing bacteria decompose complex organic compounds of humus into simple inorganic substances, making them available to plants.

   Many bacteria can fix atmospheric nitrogen. Moreover, azotobacter, free-living in the soil, fixes nitrogen independently of plants, and nodule bacteria They show their activity only in symbiosis with the roots of higher plants (mainly legumes); thanks to these bacteria, the soil is enriched with nitrogen and plant productivity increases.

   
   

   The importance of bacteria

   Symbiotic bacteria The intestines of animals (primarily herbivores) and humans ensure the absorption of fiber and form vitamins (B 12, K).

   Bacteria also play a significant role in soil formation processes.(destruction of minerals of soil-forming rocks, formation of humus).

   
   

   The importance of bacteria

   Meaning for a person:

   • Obtaining lactic acid products for pickling cabbage, ensiling feed;
   • For the production of organic acids, alcohols, acetone, enzymatic preparations;
   
   

   The importance of bacteria

   • They are actively used as producers of many biologically active substances (antibiotics, amino acids, vitamins, etc.) used in medicine, veterinary medicine and animal husbandry;
   • Thanks to genetic engineering methods, necessary substances such as human insulin and interferon are obtained with the help of bacteria;
   
   

   The importance of bacteria

   • Humans also use bacteria to purify wastewater.
   • A negative role is played by pathogenic bacteria that cause diseases of plants, animals and humans.
   • Many bacteria cause food spoilage and release toxic substances.
   
   

   Repetition:

   Continue the sentences:

   • The genetic material in prokaryotes is represented by (_).
   • Ribosomes in prokaryotes differ from eukaryotes (_).
   • Prokaryotes lack single-membrane organelles: EPS? Golgi complex? Lysosomes? Vacuoles?
   • Prokaryotes lack two-membrane organelles: Nucleus? Mitochondria? Plastids?
   • Prokaryotes reproduce (_).
   • In relation to oxygen, bacteria are divided into (_).
   • Heterotrophic organisms - (_).
   • Autotrophic organisms - (_).