RESEARCH METHODS IN CYTOLOGY Cell. Membrane organelles Cell. REMEMBRANCE ORGANELLES Nucleus, chromosome 3
RESEARCH METHODS IN CYTOLOGY 5 QUESTIONS What studies Cytology. The idea that organisms are made up of cells. Research methods used in Cytology. Cell fractionation. Autoradiography. Determination of the duration of some stages of the cell cycle by radio.
RESEARCH METHODS IN CYTOLOGY 6 What studies Cytology (I) Cytology - the science of the cell. From among other biological Sciences, it stood out almost 100 years ago. For the first time generalized information about the structure of cells were collected in the book Zh.-B. Karnua « С ell Biology", published in 1884. Modern Cytology studies : structure of cells, their functioning as elementary living systems ; the functions of individual cell components; the process of reproduction of cells and their reparations ; adaptation to environmental conditions and many other processes that allow to judge the properties and functions common to all cells. Cytology also considers the features of the structure of specialized cells.
RESEARCH METHODS IN CYTOLOGY 7 What studies Cytology (II) Cytology is closely related to Biochemistry Biophysics Molecular biology Genetics The discipline "Cytology" refers to the fundamental sections of biology, because it explores and describes the only unit of all life on Earth – the cell.
8 Cell theory In the XVII century. Robert Hooke, a physicist and biologist, characterized by great ingenuity, created a microscope. He called small units cells. in 1839, Matthias Schleiden (Germany ) and Theodor Schwann (Germany) independently formulated the cell theory
9 The main positions of the cell theory ( I ) The cell is the basis of structural and functional organization of plants and animals; Plant and animal cells are similar in structure and develop similarly (by dividing the original cell); Cells in all organisms have a membrane structure; The nucleus of a cell represents its main regulatory organoid; Cellular structure of living organisms is the evidence of the unity of their origin
10 The main positions of the cell theory (II) Additions were made to the cell theory in the period of 1855-1859 Rudolf Virchow (Germany) : Cells arise only from cells through reproduction. This point of the cell theory excludes the possibility of cell formation from the non-cellular material; The cell is a unit of pathology..
RESEARCH METHODS IN CYTOLOGY 12 Research methods in Cytology Ordinary light microscopy, which has not lost its role. Polarizing microscopy. Ultraviolet microscopy. Fluorescence microscopy. Phase-contrast microscopy. Electron microscopy
RESEARCH METHODS IN CYTOLOGY 13 Modern research methods The most useful in modern times were: 1 ) Electron microscopy; 2 ) Fractionation of cells by which biochemists can identify a relatively pure fraction of cells contain certain organelles, and to study, thus separate they are interested in metabolic reactions; 3 ) radioautography, which made it possible to directly study the individual metabolic reactions occurring in organelles.
RESEARCH METHODS IN CYTOLOGY 14 Fractionation method The method allows: to separate different organelles of the cell in a relatively pure form ; determine the chemical composition of organelles and enzymes contained in them ; on the basis of the data obtained to draw conclusions about the functions of organelles in the cell. to determine the chemical composition and enzymatic activity of the selected organelles.
15 The stages of fractionation of the cell low speed 1000 times gravity for 10 minutes medium speed 20,000 times gravity for 20 minutes high speed 80,000 times gravity for 1 hour very high speed 150,000 times gravity for 3 hours Cell fractionation by centrifugation Repeated centrifugation at progressively higher speeds will fractionate homogenates of cells into their components. In general, the smaller the subcellular component, the greater is the centrifugal force required to sediment it. Typical values for the various centrifugation steps referred to in the figure are:
RESEARCH METHODS IN CYTOLOGY 16 Literature list Molecular Biology of the Cell. 4th edition. Alberts B, Johnson A, Lewis J, et al. New York: Garland Science ; 2002
18 Questions : General outline of the cell structure Features of the structure of prokaryotic cells Comparison of plant and animal cells Characteristic of membranes Lysosomes Golgi apparatus Endoplasmic reticulum Mitochondria Plastids Vacuole Metabolic cycle in a cell
19 General outline of the cell structure Cell wall Cytoplasmic membrane Cytoplasm Golgi apparatus Lysosomes Mitochondrion Chloroplast Nucleus Smooth endoplasmic reticulum Rough endoplasmic reticulum Ribosomes Vacuole
21 SHELL ( cell wall + cytoplasmic membrane in plants or cytoplasmic membrane in animals) PROTOPLASM ( the contents of the cell ) KARYOPLASM ( nucleus substance ) CYTOPLASM ( all other contents of the cell ) CYTOSOL ( soluble part of cytoplasm ) ORGANOIDS ( structurally and functionally isolated parts of the cytoplasm ) SPARE NUTRIENTS ( organic and inorganic ) Cell MEMBRANOUS Lysosomes, Golgi apparatus, endoplasmic reticulum, mitochondria, plastids Non-MEMBRANE Cell center, microtubules, microfilaments, cilia, flagella
22 Features of the prokaryotic structure Capsule ( pectin mucosa ) Cell wall Cytoplasmic membrane (CPM ) Nucleoid Plasmids Mesosome Ribosomes (size - Fimbriae (pili ) Flagellum Cytoplasm ( ring DNA, membrane of the cytoplasm is not separated ) ( contains murein, not cellulose ) Photosynthetic membrane ( invagination inside the CPM cells, a functional analog of the chloroplast ) ( invagination inside the CPM cells, a functional analog of the mitochondrial ) ( flagellin's protein thread moves due to the rotation of the inner ring, not the contraction of the thread itself ) (70 S, but not 80 S ) ( contain additional genetic material ) ( attachment to substrate and absorption of nutrients )
23 Comparison of plant and animal cells : TYPE OF NUTRITION AUTOTROPHIC ( synthesis of organic substances from inorganic ) HETEROTROPHIC ( synthesis of organic substances only from organic Plant cell Animal cell Cell wall PLASTIDS ( the organelles responsible for autotrophic type of nutrition ) VACUOLE in lower animals performs a digestive function ATP synthesis mitochondria, chloroplasts mitochondria CELLULAR CENTRE only in lower animals SPARE CARBOHYDRATES starch glycogen
25 Biological membrane Protein molecules (80-20%) immersed in lipid bilayer (20-80%) GLYCOCALYX PERIPHERAL PROTEINS INTEGRAL PROTEINS 7-21 нм protein protein lipid lipid recognition of external signals adhesion of cells in the tissue immune response form a hydrophilic channel - pore transported through the membrane of certain substances (are carriers ) Shell or part of the cell shell they are part of the cell membrane organoids (the principle of compartmentalization) in EUKARYOTES ) they are part of the membrane cell formations in PROKARYOTES
32 Transport of substances through the plasma membrane ACTIVE TRANSPORT PASSIVE TRANSPORT (DIFFUSION ) ENDOCYTOSIS EXOCYTOSIS PHAGOCYTOSIS PINOCYTOSIS TRANSFER PENETRATION Ordinary DIFFUSION Facilitated DIFFUSION Binding of the dissolved substance Carrier inversion Release of dissolved substance PERMEASE As well as the active transport is carried out by using protein vectors
41 Hypotheses of increasing the number of mitochondria in a cell : Mitochondria are formed from precursors ( promitochondria ) Mitochondria are formed from other membrane organelles of the cell The increase in the number of mitochondria in the cell occurs as a result of the division of the mitochondria
RESEARCH METHODS IN CYTOLOGY 47 Questions : Cell wall Microtubules Microfilament Cell center Ribosomes
49 Cell wall in bacteria
60 Questions : Structure and functions of the nuclear apparatus of the cell Definition of chromosome Structure and function of chromosomes Types of chromosomes Chromosomes of "tube brushes" type Polytene chromosomes B-chromosomes
62 Chromosome The chromosome is a permanent component of the nucleus, characterized by a special structure, personality, function and ability to reproduce itself, which ensures the continuity and transmission of hereditary information from one generation of living organisms to another. Its name was due to the ability to intensely colored basic dyes. The term "chromosome" was proposed in 1888 by Valldaura.
72 Functions of chromosomes 1. Information - contains DNA, which contains qualitatively different genes that make up the genome of the cell. 2. Transcription – the reading of the information contained therein in the course of gene expression. 3. Structural and organizational - provides extremely accurate reproduction of chromosomes during replication and identity of child chromosomes diverging to the poles. 4. Segregation - provides distribution of chromosomes along the poles in different spores or gametes in meiosis. 5. Recombination - provides a significant part of the combinative variability - recombination of linked genes.
73 Karyotype Karyotype - chromosomal complex species with its own characteristics: the number and size of chromosomes; their morphology; the presence of under a light microscope parts of the structure, constrictions, satellites, shoulder ratio, alternation of EU-and heterochromatin. The most important property of the karyotype is the presence of pairs of homologous chromosomes.
81 Polytene chromosomes It was discovered in 1881 by Balbiani Characteristics: in terms of volume, about 1000 times more somatic due to 9 – 10 consecutive replication; the cell cycle in cells of this type consists of only 2 phases: synthesis of DNA and synthetic period; polytene chromosomes are not able to enter into mitotic divisions. VALUE: due to polyteny, the body mass increases much faster than due to mitotic divisions of diploid cells.
84 CHROMOSOME TYPE "OF TUBE BRUSHES » Were opened In 1878 by W. Fleming Can be found in meiosis at the stage of prophase I, in diplotene Formed in the course of extremely long meiotic division. Chromosomes of type "Tube brushes" – diplotene bivalent, consisting of two chromosomes, which intersect in the points a chiasm.
85 The generally accepted parts of modern cell theory include : All known living things are made up of one or more cells All living cells arise from pre-existing cells by division. The cell is the fundamental unit of structure and function in all living organisms. The activity of an organism depends on the total activity of independent cells. Energy flow ( metabolism and biochemistry ) occurs within cells. Cells contain DNA which is found specifically in the chromosome and RNA found in the cell nucleus and cytoplasm. All cells are basically the same in chemical composition in organisms of similar species.
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