RAYAT SHIKSHAN SANSTHA SATARA KARMAVEER VIDYA PRABODHINI SATARA

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, SATARA. MADHYA VIBHAG POWERPOINT PRESENTATION 9 TH STD. -SCIENCE & TECHNOLOGY WITH SYLLABUS 2011 -12 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA UNIT : - CELL : 5. THE UNIT OF LIFE SUB UNITS : -5. 1 CELL AS A BASIC UNIT OF LIFE 5. 2 -STRUCTURAL ORGANIZATION OF A CELL 5. 3 - CELL ORGANELLES 5. 4 - PROKARYOTIC & EUKARYOTIC CELL : THE UNIT OF LIFE 9 TH 5. CELL: THE UNIT OF LIFE STD. TECH-PPT SCIENCE &

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA CELL AS A BASIC UNIT OF LIFE Every structure is made up of certain building blocks. It was Robert Hooke, in year 1665 first discovered these building blocks when he observed a thin slice of cork [bark of trees ] under his self designed microscope. These compartments of cork were empty. He found they resembled the structure of honey comb and labelled them, ‘cells’ which in Latin means ‘small rooms’, but these cell were dead. There are 25 million RCBs cell. Every living thing, however different, is made up of these separate tiny units called “CELLS. ” 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA ANTON VAN LEEUWENHOEK - 1673 This Dutch lens grinder invented the instrument that we recognize as the microscope today. Contributors TO THE STUDY OF CELLS Zacharias Jansen 1590 – First invented microscope. Robert Hooke 1665 - Discovered dead cells from cork. Leeuwenhoek 1674 - First observed living cells of bacteria , sperm, protozoan. Robert Brown 1831 - Demonstrated the presence of nucleus in the cell. Johannes Purkinje 1839 - Named the fluid content of the cells protoplasm 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Cell theory It was proposed by M. J. Schleiden and Theodore Schwann [1838 -39] that ‘All plants are composed of cell and cell is the basic unit of life. ’ In 1885 R. Virchow modified this theory as “Omnis celula a cellula” i. e. all cells arise from existing cells. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Modern cell theory has following postulates: - All organisms are composed of cell. Cell is the structural and functional unit of life. All cells arise from pre-existing cells. Every organism starts its life as a single cell. With discovery of electron microscope in 1940, it was easy to understand the complex structure of a cell and its organelles. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Morphology of cells: - a] Cell – how big or small An egg and an amoeba both are single cells. Size of the cell varies greatly {0. 1 um to 18 cm} The unit used to measure size of a cell is micrometer{um} 1 micrometer = 1 / 1000 millimeter. Smallest cell - Cells of Mycoplasma galliseptium {0. 1 um} Egg of an ostrich - {18 cm} is also a single, largest cell. Some never cells in humans have one m long tail or axon. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Similar to the mosquito net plasma membrane also permits the entry and exit of some materials in and out of the cells, while preventing the other materials to do so. Therefore it is called a selectively permeable membrane. 1. Useful molecules enter the cell. {e. g. water, salt} 2. Useful products remain in the cell. {e. g. enzymes, proteins } 3. Waste and other secretions leave the cell {e. g. carbon dioxide } and homeostasis i. e. a constant internal environment is maintained inspite of changes outside. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Osmosis Plasma membrane being of water from a region of high water concentration through a selectively permeable membrane to a region of low water concentration is called Osmosis. This is a pure mechanical process, by which the cell gains water without spending energy. When a cell is placed into a solution of sugar or salt there are three possible situation. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Situations: 1. Medium surrounding the cell has same water concentration as that of the cell. 2. Medium surrounding the cell has higher water concentration that of the cell. TH Medium the cell has 93. 5. surrounding CELL: THE UNIT OF LIFE SCIENCE STD. lower water concentration than& that TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Diffusion and osmosis along with osmosis , diffusion also play a role in exchange of material in and out of the cell with out spending energy. Transport of some other molecules like insulin also take place in and out of the cell. These active cellular process need energy. They are called as Endocytosis and exocytosis. Difference between diffusion and osmosis: - Diffusion It occurs in any medium. Osmosis It requires liquid medium. The diffusing molecules can be It involves movement of only solid, solvent molecules. Liquid, or gases. Semipermeable membrane is 9 TH required. 5. CELL: THE UNIT OF LIFE SCIENCE not required. STD. & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA NUCLEUS Chromatin fibres are thin thread like structure Composed of DNA and proteins. DNA molecules transfer the hereditary information from one Generation to the next. is called DNA. Functions: 1. In controls all metabolic activities of the cell. 2. Nucleus controls cell division. 3. It is involved in transmission of hereditary characters from parents to off springs. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Function of er 1. Along with intracellular transport it also acts. as a supportive framework for a cell. 2. It synthesizes proteins and lipids and transports them. Some lipids synthesized by it are used in building plasma membrane while some other lipids and proteins are used as hormones and enzymes. 3. It transports proteins synthesized by ribosomes. 4. SER of certain cells of liver play a crucial role in detoxifying many proteins and drugs which enter our body through food, air or water. It makes the toxins water soluble so that they may be exerted through urine. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Golgi complex was first described by a German scientist “ Camillo Golgi ”. It Comprises of five to eight sacs which resemble deflated balloons placed approximately parallel to each other. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Lysosomes: - Due to various metabolic activities going On in the cell, organic waste is gene rated. Lysosomes digest the waste. Lysosomes are Simple one membrane bound sacs, filled with digestive enzymes. These powerful enzymes are made by RER and are capable of digesting and Breaking down all organic matter. It is the cell’s Waste disposal system. Lysosomes are absent in Plant cells. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Mitochondria Ø Ø Mitochondria produce the energy rich compound ATP which is the energy currency of the cell. The body uses the energy stored in ATP to synthesize chemical compounds and to do mechanical work. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA Vacuoles: q q Vacuoles help to maintain osmotic pressure of the cell. They stored metabolic byproducts and end products. They stored waste products and food in animal cell. In plant cells, vacuoles are full of cell sap and provide turgidity and rigidity to them. 9 TH STD. 5. CELL: THE UNIT OF LIFE SCIENCE & TECH-PPT

RAYAT SHIKSHAN SANSTHA, SATARA KARMAVEER VIDYA PRABODHINI, MADHYA VIBHAG, SATARA MAHARAJA SAYAJIRAO VIDYALAYA , SATARA (I. S. O. 9001– 2011. . 12) Nikam S. R.