Cell

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An Introduction To Biochemical Aspects Of Animal Cell.

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Cell

  1. 1. Biochemical Aspects Of Cell
  2. 2. Beginning of life on earth is still a mystery ! BUT <ul><li>All multicellular creatures begin their life as a single cell e;g., </li></ul><ul><ul><li>Fertilized ovum. </li></ul></ul><ul><ul><li>Seed. </li></ul></ul>
  3. 3. Cell is Structural & Functional Unit of an Organism All organisms are made up of cells <ul><li>Consisting of: </li></ul><ul><ul><li>Membrane. </li></ul></ul><ul><ul><li>Nucleus. </li></ul></ul><ul><ul><li>Cytoplasm. </li></ul></ul><ul><ul><li>Organelles. </li></ul></ul><ul><li>Capable of: </li></ul><ul><ul><li>Growth. </li></ul></ul><ul><ul><li>Reproduction. </li></ul></ul><ul><ul><li>Independent Functioning. </li></ul></ul>
  4. 4. Different types of cells are different in their minute Structure & Functions <ul><li>Cells of human body are divided into a variety of types, Such as: </li></ul><ul><ul><li>Muscle cells. </li></ul></ul><ul><ul><li>Nerve cells. </li></ul></ul><ul><ul><li>Connective tissue cells. </li></ul></ul><ul><ul><li>Epithelial cells etc. </li></ul></ul><ul><li>Collective Behaviour of a system is the collaborated functions of individual cells. </li></ul>
  5. 5. Fundamental Structural and Functional Organisation of all cells are Similar <ul><li>Although different types of cells are different in their minute structure & functions but the fundamental structural and functional organisation of all cells are similar. </li></ul>
  6. 6. Why We Need To Understand Cells? <ul><li>All the functions take place at the cellular level: </li></ul><ul><ul><ul><li>From simple digestion to delicate process of Growth & R eproduction . </li></ul></ul></ul><ul><ul><ul><li>From minor sickness to life threatening diseases like cancer. </li></ul></ul></ul><ul><ul><ul><li>From minor injury like a simple skin cut to grievous injuries like brain damage. </li></ul></ul></ul><ul><ul><ul><li>Healing of a simple wound to repair of bone fracture. </li></ul></ul></ul>
  7. 7. Why? The Study of cell is a logical starting point of medical education. <ul><li>Structural and functional unit. </li></ul><ul><li>Collective Behaviour of a system is the collaborated functions of individual cells. </li></ul><ul><li>Diseases begin in the cell. </li></ul><ul><li>Any abnormal change occurs at the level of single cell. </li></ul>
  8. 8. Thorough Knowledge of Structure and Function of cell is Necessary to Understand Modern aspects of medical sciences like: <ul><li>Biotechnology </li></ul><ul><li>Gene splicing </li></ul><ul><li>Human genome </li></ul><ul><li>Genetic engineering </li></ul><ul><li>Recombinant DNA </li></ul><ul><li>Genetic diseases </li></ul><ul><li>Gene therapy </li></ul><ul><li>DNA mutations </li></ul><ul><li>DNA fingerprinting or DNA profiling. </li></ul>
  9. 9. Living Systems Have Different Levels of Organization. <ul><li>Cell (The Lowest Level): The simplest level of organization. </li></ul><ul><li>Tissue: A group of cells with a similar function. </li></ul><ul><li>Organs: Groups of tissues working together to perform a common function. </li></ul><ul><li>Organ system (The Highest Level): Groups of organs working together to </li></ul><ul><ul><li>perform a common function. </li></ul></ul>
  10. 10. Tissue Cell Organs System
  11. 11. Structural Organization of Animal Cell <ul><li>Cell Membrane. </li></ul><ul><li>Protoplasm (Bioplasm). </li></ul><ul><ul><li>The Living Substance Inside the Cell. </li></ul></ul><ul><ul><li>Organized Colloidal Complex of Organic and Inorganic Substances (as Proteins and Water) </li></ul></ul><ul><ul><li>At the simplest level, it is divisible into </li></ul></ul><ul><ul><ul><li>Cytoplasm. </li></ul></ul></ul><ul><ul><ul><li>Nucleus. </li></ul></ul></ul>
  12. 12. Compartments in Protoplasm <ul><li>Cytoplasm: </li></ul><ul><ul><li>Portion of Protoplasm Surrounded by Cell membrane Present Outside the Nucleus. </li></ul></ul><ul><li>Nucleoplasm: </li></ul><ul><ul><li>Portion of Protoplasm Surrounded by Nuclear Membrane. </li></ul></ul>
  13. 13. Cytoplasm & Nucleoplasm Have Fluid Part and Insoluble Structures <ul><li>Cytoplasm : </li></ul><ul><ul><li>Cytosol (Fluid Part). </li></ul></ul><ul><ul><li>Insoluble Structures (Surrounded By Membranes). </li></ul></ul><ul><li>Nucleoplasm : </li></ul><ul><ul><li>Fluid Part (Water & Solutes). </li></ul></ul><ul><ul><li>Chromatin. </li></ul></ul>
  14. 15. CYTOPLASM <ul><li>Gelatinous, Semi-Transparent Fluid That Lies Within The Cell Membrane, But Outside The Nucleus. </li></ul><ul><li>Organized complex of inorganic and organic substances </li></ul><ul><li>Fills Most Cells in Which The Other Cytoplasmic Elements Are Suspended. </li></ul>
  15. 16. Components of Cytoplasm <ul><li>Fluid part (Cytosol). </li></ul><ul><ul><li>About 70% of the cell </li></ul></ul><ul><ul><li>Composed of: </li></ul></ul><ul><ul><ul><li>Water. </li></ul></ul></ul><ul><ul><ul><li>Solutes. </li></ul></ul></ul><ul><ul><ul><ul><li>Organic Substances. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Inorganic substances. </li></ul></ul></ul></ul><ul><li>Physical Structures. </li></ul>
  16. 17. Cytosol is the Fluid component of Cytoplasm Excluding Organelles and the Insoluble Components.
  17. 18. Organic Solutes of Cytosol <ul><ul><ul><li>Proteins & Amino acids. </li></ul></ul></ul><ul><ul><ul><li>Enzymes. </li></ul></ul></ul><ul><ul><ul><li>Carbohydrates. </li></ul></ul></ul><ul><ul><ul><li>Lipids. </li></ul></ul></ul><ul><ul><ul><li>Vitamins. </li></ul></ul></ul><ul><ul><ul><li>Nucleic acids. </li></ul></ul></ul>
  18. 19. <ul><li>Mineral salts </li></ul><ul><ul><ul><ul><ul><li>NaCl </li></ul></ul></ul></ul></ul><ul><li>Gases </li></ul><ul><ul><ul><ul><ul><li>Oxygen </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Carbon dioxide. </li></ul></ul></ul></ul></ul>Inorganic Solutes of Cytosol
  19. 20. Functions of Cytoplasm <ul><li>Support. </li></ul><ul><li>Site for most cellular activities. </li></ul><ul><li>Maintain cell shape. </li></ul><ul><li>cell motility. </li></ul>
  20. 21. <ul><li>Provides a platform in which Organelles and Inclusions are Suspended. </li></ul><ul><li>Provides Aqueous Media to Keep Proteins, Enzymes and other Solutes in Dissolved Form so that Remain Equally Distributed. </li></ul>Supporting Functions of Cytoplasm
  21. 22. <ul><li>All of the functions such as respiration, protein synthesis, energy generation etc. are carried out in Cytosol and organelles. </li></ul><ul><li>The cytosol has enzymes that Break Large molecules, so that the organelles can use them as they need to. </li></ul>Cytoplasm is Site for Most cellular activities
  22. 23. Functions of a Multicellular Organism such as, Growth , Reproduction, Respiration, Excretion etc. are the Ultimate Result of Individual Cellular Activities <ul><li>Two Major Types Of Functions: </li></ul><ul><ul><li>Vital Functions. </li></ul></ul><ul><ul><li>Specified Functions. </li></ul></ul>
  23. 24. Vital Functions <ul><ul><li>Growth. </li></ul></ul><ul><ul><li>Reproduction. </li></ul></ul><ul><ul><li>Respiration (Generation of Energy by Oxidation Of food Stuffs) </li></ul></ul>
  24. 25. Specified Functions <ul><li>Transmission of Messages (Sensory & Motor) by Nerve Cells. </li></ul><ul><li>Synthesis of Hormones by Endocrine Glands. </li></ul><ul><li>Synthesis of digestive Enzymes by Salivary Glands, Stomach, Intestine, Pancreas etc. </li></ul><ul><li>Contraction & Relaxation of Muscles. </li></ul><ul><li>Synthesis & Storage of Fats (Energy) by Adipocytes. </li></ul><ul><li>Many More! </li></ul>
  25. 26. Two Major Requirements For Cell Functions <ul><li>Synthesis of Biomolecules. </li></ul><ul><ul><li>Proteins & Enzymes. </li></ul></ul><ul><ul><li>Carbohydrates. </li></ul></ul><ul><ul><li>Lipids. </li></ul></ul><ul><ul><li>Nucleic Acids. </li></ul></ul><ul><li>Energy Generation: </li></ul><ul><ul><li>Chemical Energy. </li></ul></ul><ul><ul><li>Mechanical Energy. </li></ul></ul><ul><ul><li>Thermal Energy. </li></ul></ul>
  26. 27. Cellular Function are Based on Metabolism <ul><li>Metabolic Reactions are essence of life. </li></ul><ul><li>A metabolic reaction is defined as Any Chemical Reaction Taking Place In a Living Cell: </li></ul><ul><ul><li>Simple or Complex. </li></ul></ul><ul><ul><li>Normal or Abnormal. </li></ul></ul>
  27. 28. Purpose of metabolic reaction may be: <ul><li>Anabolism , Synthesis of substances, necessary for Growth, Reproduction, Repair and formation of biological compounds. </li></ul><ul><ul><ul><li>Proteins. </li></ul></ul></ul><ul><ul><ul><li>Enzymes. </li></ul></ul></ul><ul><ul><ul><li>Hormones. </li></ul></ul></ul><ul><ul><li>Anabolic Reactions Require Energy. </li></ul></ul><ul><li>Catabolism , Breakdown of substances For energy generation ( Glycolysis, Lipolysis ). </li></ul><ul><ul><ul><li>Carbohydrates. </li></ul></ul></ul><ul><ul><ul><li>Lipids. </li></ul></ul></ul><ul><ul><ul><li>Nucleic Acids. </li></ul></ul></ul>
  28. 29. Cellular Activities Required to Maintain Normal Life are Based on Specific Metabolic Processes <ul><li>Growth: </li></ul><ul><ul><li>Synthesis of Proteins & Other Compounds. </li></ul></ul><ul><li>Reproduction (Mitosis): </li></ul><ul><ul><li>DNA replication. </li></ul></ul><ul><li>Energy Generation (Respiration): </li></ul><ul><ul><li>Catabolism of Glucose, Fats and Other Molecules. </li></ul></ul>
  29. 30. Many Other Cellular Activities are also Required to Maintain Normal Life <ul><li>Aggregation & storage: Of Synthesized Products. </li></ul><ul><li>Intracellular Transport: Transport of the products to different parts of cell. </li></ul><ul><li>Digestion: Complex nutritional compounds like Carbohydrates, Proteins and Fats. </li></ul><ul><li>Defence: Against Injurious Agents. </li></ul>
  30. 31. Many Other Cellular Activities are also Required to Maintain Normal Life <ul><li>Cell Motility : Cell Locomotion and internal movement of organelles. </li></ul><ul><li>Excretion: Cells must get rid of excretory wastes; they usually diffuse out of the cell through the cell membrane. </li></ul><ul><li>Irritability: The living protoplasm responds to stimuli, e.g. retinal cells in the eye respond to light. </li></ul>
  31. 32. Overall Behaviour of Human body is Collaborated Functions of Organs <ul><li>Functions of an individual organ are due to collective activities of various types of cells present in that organ. </li></ul>
  32. 33. Specific Cellular Activities are Performed In Different Compartments Of Cell <ul><li>Overall Behaviour of Cell is Collaborated Functions of: </li></ul><ul><ul><ul><li>Cell Membrane. </li></ul></ul></ul><ul><ul><ul><li>Cytosol. </li></ul></ul></ul><ul><ul><ul><li>Organelles. </li></ul></ul></ul><ul><ul><ul><li>Nucleus. </li></ul></ul></ul>
  33. 34. Specific Cellular Activities In Cytosol <ul><li>Glycolysis: </li></ul><ul><ul><li>Initial Stage Of Carbohydrate Breakdown (Catabolism) & Generation Of Energy. </li></ul></ul><ul><li>Biosynthesis of: </li></ul><ul><ul><li>Fatty Acids. </li></ul></ul><ul><ul><li>Glucose & Other Sugars. </li></ul></ul><ul><ul><li>Amino Acids. </li></ul></ul>
  34. 35. Organelles Are Metabolic Machinery of the Cell <ul><li>All the functions of life take place in each individual cell. </li></ul><ul><li>Within cells there is a network of physical structures work like different organs of our body So Called Organelles. </li></ul><ul><li>Cell organelles are the little workhouses within the cell. </li></ul>
  35. 36. Metabolic machinery of the cell: <ul><li>Like little organs themselves. </li></ul><ul><li>Always present. </li></ul><ul><li>The major organelles that are suspended in the cytosol are: </li></ul><ul><ul><li>Mitochondria. </li></ul></ul><ul><ul><li>Endoplasmic reticulum. </li></ul></ul><ul><ul><li>Ribosomes </li></ul></ul><ul><ul><li>Golgi apparatus. </li></ul></ul><ul><ul><li>Lysosome. </li></ul></ul><ul><ul><li>Cytoskeleton. </li></ul></ul>ORGANELLES
  36. 37. All Organelles have unique functions and perform specific jobs <ul><li>Mitochondria; Cellular Respiration. </li></ul><ul><li>Endoplasmic reticulum; Synthesis of Compounds. </li></ul><ul><li>Ribosomes; Synthesis of Proteins. </li></ul><ul><li>Golgi apparatus; Aggregation, Packaging, Storage and Exportation of the Products Synthesized Within ER. </li></ul><ul><li>Lysosome; Digestion of Macromolecules. </li></ul>
  37. 38. Mitochondrion (Chondriosome) <ul><li>Spherical or elongated organelle. </li></ul><ul><li>Responsible for cellular respiration. </li></ul><ul><li>Cellular Respiration </li></ul><ul><ul><li>Conversion of food to usable energy. </li></ul></ul><ul><ul><ul><li>The series of metabolic processes by which living cells produce energy through the oxidation of organic substances. </li></ul></ul></ul>
  38. 39. Mitochondrion Matrix Inter Membrane Space Outer Membrane Inner Membrane Folded Inside To Form Cristae
  39. 40. Mitochondrion Energy yielding metabolic processes  Biological Oxidation (Respiratory Chain).  Oxidative Phosphorylation.  Citric Acid Cycle.  Oxidation of Fatty Acids. CO, CN and other deadly Poisons cause Death because they block the energy yielding reactions in Mitochondria.
  40. 41. Cut Section of Mitochondrion
  41. 42. Mitochondria (Chondriosomes) are Powerhouse of cells <ul><li>Cellular Respiration (Energy Generation): </li></ul><ul><ul><li>Oxidation of Fatty Acids </li></ul></ul><ul><ul><li>Citric Acid Cycle: </li></ul></ul><ul><ul><ul><li>Final Catabolism of Glucose, Fats and Amino Acids. </li></ul></ul></ul>
  42. 43. Mitochondria are site for many other Specific Cellular Activities <ul><li>Heme synthesis. </li></ul><ul><li>Steroid synthesis. </li></ul><ul><li>Detoxification of Ammonia (in liver cells). </li></ul>
  43. 44. Mitochondrial Medicine <ul><li>A New and Rapidly Developing Medical Subspecialty that deals with Mitochondrial Diseases (Mitochondrial Cytopathies) </li></ul>
  44. 45. Mitochondrial Diseases (Mitochondrial Cytopathies) <ul><li>Abnormality of one or more functions of Mitochondria. </li></ul><ul><li>Include > 40 different identified diseases. </li></ul><ul><li>The common factor is the biochemical defect that makes the mitochondria unable to completely burn food and oxygen in order to generate energy. </li></ul>
  45. 46. Depending on which cells of the body are affected, Mitochondrial Diseases may result in: <ul><li>Poor growth. </li></ul><ul><li>Muscle Weakness and Loss of coordination. </li></ul><ul><li>Visual Problems & Hearing Problems. </li></ul><ul><li>Mental retardation. </li></ul><ul><li>Heart, liver, or kidney disease. </li></ul><ul><li>Gastrointestinal disorders. </li></ul><ul><li>Respiratory disorders. </li></ul><ul><li>Increased risk of infection. </li></ul><ul><li>Neurological problems, seizures. </li></ul><ul><li>Thyroid dysfunction. </li></ul><ul><li>Dementia (mental disorder characterized by confusion, disorientation, and memory loss). </li></ul>
  46. 47. Endoplasmic Reticulum is Interconnected Network of branching canals and vesicles
  47. 48. Endoplasmic Reticulum is Interconnected Network of: Tubules Vesicles Sacs (Cisternae)
  48. 49. Two Types Of Endoplasmic Reticulum <ul><li>Granular or Rough </li></ul><ul><li>Agranular or Smooth </li></ul>Ribosomes
  49. 50. Endoplasmic Reticulum is Membrane Bound Organelle Involved in Synthesis of Proteins & other Compounds <ul><li>Two types of Endoplasmic Reticulum. </li></ul><ul><li>Granular or Rough ER. </li></ul><ul><ul><li>Studded with Ribosomes. </li></ul></ul><ul><ul><li>Synthesis of proteins . </li></ul></ul><ul><li>Agranular or smooth ER. </li></ul><ul><ul><li>Synthesis of Lipids, Glycogen etc. </li></ul></ul>
  50. 51. RER Is the Site for Protein Synthesis <ul><li>A variety of Proteins are synthesized by RER: </li></ul><ul><ul><li>Membranes proteins. </li></ul></ul><ul><ul><li>Other proteins synthesized depends on the specificity of cell such as: </li></ul></ul><ul><ul><ul><li>In Leukocytes the Rough ER Produces Antibodies. </li></ul></ul></ul><ul><ul><ul><li>In Pancreatic Cells the Rough ER Produces Insulin. </li></ul></ul></ul>
  51. 52. Each cell contains thousands Miniature “Protein Factories” The Ribosomes <ul><li>Non-membranous, bodies. </li></ul><ul><li>Consists of two subunits </li></ul><ul><ul><li>Large. </li></ul></ul><ul><ul><li>Small. </li></ul></ul><ul><ul><li>Each of which has a characteristic shape. </li></ul></ul>
  52. 53. A ribosome is a small, dense, functional structure found in all known cells that assemble proteins <ul><li>Contain RNA, Enzymes & Amino acids necessary for protein synthesis. </li></ul><ul><li>Ribosomes occur as: </li></ul><ul><ul><li>Free particles (Polysomes) within cells. </li></ul></ul><ul><ul><li>Particles attached to the membranes of the endoplasmic reticulum (So called Rough ER). </li></ul></ul>
  53. 54. Ribosomes Are Embedded On Surface Of ER Or Found Free In Cytoplasm <ul><li>Stationary type: </li></ul><ul><ul><li>Embedded On surface of ER. </li></ul></ul><ul><ul><li>Injects Proteins In Tubular Network Of Endoplasmic Reticulum. </li></ul></ul><ul><li>Mobile type: </li></ul><ul><ul><li>Found Floating Free (Unbound To Membrane) As Polysomes In Cytoplasm. </li></ul></ul><ul><ul><li>Injects Proteins Directly Into Cytoplasm. </li></ul></ul>
  54. 55. Protein Synthesis Can be Interrupted By External Factors <ul><li>Antibiotics: </li></ul><ul><ul><li>Many of the antibiotics used to treat bacterial infections specifically inhibit ribosome activity in the bacteria. </li></ul></ul><ul><li>Viruses, Radiations or Other injurious agents: </li></ul><ul><ul><li>May produce Diseases by disturbing Protein synthesis in Ribosomes. </li></ul></ul>
  55. 56. The Smooth ER Has a Wide Range Of Functions <ul><li>Synthesis of: </li></ul><ul><ul><li>Glycogen. </li></ul></ul><ul><ul><li>Lipids. </li></ul></ul><ul><ul><li>Steroid hormones. </li></ul></ul>
  56. 57. The Rough and Smooth ER Are Usually Interconnected <ul><li>Proteins & other Products made by Rough ER, move & isolated in Sacs (Cisternae) of Smooth ER. </li></ul>
  57. 58. ER & Intracellular Transport <ul><li>The ER is additionally responsible for moving Proteins, Carbohydrates and other products to appropriate locations for further processing. </li></ul><ul><li>Proteins & other products are transported to: </li></ul><ul><ul><li>Golgi Apparatus. </li></ul></ul><ul><ul><li>Plasma Membrane. </li></ul></ul><ul><ul><li>Lysosomes. </li></ul></ul>
  58. 59. Golgi Apparatus (Golgi Body or Golgi Complex) Network of membranous tubules and vesicles present in most living cells
  59. 60. Golgi Apparatus is In Direct connection with ER <ul><li>Involved in the Aggregation, Packaging, Storage and Exportation of the Products Synthesized Within ER. </li></ul><ul><li>Site for the Formation of Lysosomes. </li></ul><ul><ul><li>Aggregation & Packaging of Lysosomal Enzymes </li></ul></ul>
  60. 61. Golgi Apparatus is involved in secretory functions of cells <ul><li>Golgi Apparatus seems to be Involved in the Aggregation, Packaging and Storage of secretions of Gland cells. </li></ul><ul><li>Golgi Bodies are located: </li></ul><ul><ul><li>Near the Nucleus in Non-Secretory Cells like Nerve cells. </li></ul></ul><ul><ul><li>Near Periphery Close to Cell Membrane in Secretory Cells such as Glands. </li></ul></ul>
  61. 62. Lysosomes are Small and Simple Membranous Sacs, Contain Digestive Enzymes. Membrane Enzymes
  62. 63. Lysosome is a cellular organelle responsible for intracellular digestion and recycling of macromolecules. <ul><li>Some important enzymes found within lysosomes include: </li></ul><ul><ul><li>Lipase, which digests lipids. </li></ul></ul><ul><ul><li>Amylase, which digest carbohydrates (e.g., sugars). </li></ul></ul><ul><ul><li>Proteases, which digest proteins. </li></ul></ul><ul><ul><li>Nucleases, which digest nucleic acids. </li></ul></ul>
  63. 64. Lysosomes: Autolysis of Dead Cell Material <ul><li>Digestion of Defective Organelles: </li></ul><ul><ul><li>Digestion compartments for cellular materials that have completed their lifespan or are otherwise no longer useful. </li></ul></ul><ul><li>This function of the lysosome makes it sort of a scavenger. </li></ul>
  64. 65. Lysosomes have about 40 different types of digestive enzymes <ul><li>To accomplish the tasks associated with digestion: </li></ul><ul><ul><li>The lysosomes utilize about 40 different types of hydrolytic enzymes. </li></ul></ul><ul><ul><li>All of which are manufactured in the endoplasmic reticulum and modified in the Golgi Bodies. </li></ul></ul>
  65. 66. <ul><li>Lysosomes are found in all animal cells, but are most numerous in disease-fighting cells, such as white blood cells. </li></ul><ul><li>This is because white blood cells must digest more material than most other types of cells in their quest to battle bacteria, viruses, and other foreign intruders. </li></ul>Lysosomes: Defence against living Bacteria
  66. 67. Lysosomes Allow the Cell to Recycle the Valuable Nutrients <ul><li>Digested cellular waste products are transferred back into the cytoplasm as new cell-building materials. </li></ul><ul><li>So the lysosomes allow the cell to recycle the valuable nutrients that would have to be thrown out. </li></ul><ul><li>Conserves Nutrients so the cell is eating part of itself instead of getting rid of it (Autophagy). </li></ul>
  67. 68. Why Don't Lysosomes Digest the Cell? <ul><li>Lysosomal Membrane protects the rest of the cell from the harsh digestive enzymes contained in the lysosomes, which would otherwise cause significant damage. </li></ul><ul><li>With an average pH of about 4.8, the Lysosomal matrix is favorable for enzymatic activity, but the neutral environment of the cytosol renders most of the digestive enzymes inoperative. </li></ul>
  68. 69. Diseases Due to Absence of Lysosomal Enzymes <ul><li>In Humans, a Variety of Inherited Conditions can Affect Lysosomes. </li></ul><ul><li>These Defects are Called Lysosomal Storage Diseases (LSD). </li></ul><ul><li>Most lysosomal storage diseases are progressive and Life threatening. </li></ul>
  69. 70. Lysosomal Storage Diseases (LSD) are due to absence or deficiency of enzyme(s) <ul><li>People with these disorders are missing one or more of the lysosomal enzymes. </li></ul><ul><li>Undigested Molecules build up within the lysosome, and prevent the cell from working properly. </li></ul><ul><li>Unwanted Accumulation (Storage) of Molecules is the Major Hazard in Lysosomal Storage Diseases (LSD) </li></ul>
  70. 71. Excessive Storage of Molecules is the Major Hazard of LSDs <ul><li>Lipid storage Diseases: </li></ul><ul><ul><li>Tay-Sachs. </li></ul></ul><ul><ul><li>Fabry’s disease. </li></ul></ul><ul><ul><li>Gaucher’s disease. </li></ul></ul><ul><ul><li>Krabbe’s disease. </li></ul></ul><ul><ul><li>Niemann-Pick disease. </li></ul></ul><ul><li>Carbohydrate storage disease: </li></ul><ul><ul><li>Mucopolysacchiradosis. </li></ul></ul><ul><ul><li>Pompe disease. </li></ul></ul>
  71. 72. Common clinical findings in LSDs <ul><li>Mental retardation. </li></ul><ul><li>Enlarged liver & spleen. </li></ul><ul><li>Blindness muscular weakness. </li></ul><ul><li>Kidney failure. </li></ul><ul><li>Skin rashses. </li></ul>
  72. 73. Lysosomes are involved in Programmed Cell Death: Apoptosis. <ul><li>Cell suicide, Also Known as Programmed Cell Death In Good Faith Of Organism. </li></ul><ul><li>They are frequently nicknamed &quot;suicide-bags&quot; or &quot;suicide-sacs&quot; by cell biologists due to their role in autolysis. </li></ul>
  73. 74. The Lysosomsal Membrane Allows Only Small Particles To Exit It. <ul><li>This structural asset assures that only molecules which have been digested into smaller parts can exit the lysosome. </li></ul><ul><li>This makes sure that all the material that leaves the lysosome is properly digested. </li></ul>
  74. 75. INCLUSIONS <ul><li>Chemical substances that store: </li></ul><ul><ul><li>Nutrients. </li></ul></ul><ul><ul><li>Secretory Products. </li></ul></ul><ul><ul><li>Pigment Granules. </li></ul></ul><ul><li>Temporary Products of cellular activity. </li></ul><ul><ul><li>Fat droplets. </li></ul></ul><ul><ul><li>Carbohydrate particles. </li></ul></ul><ul><ul><li>Pigment granules. </li></ul></ul><ul><ul><li>Crystals. </li></ul></ul><ul><ul><li>Secretory granules. </li></ul></ul>
  75. 76. <ul><ul><li>Organized Network of Microtubules that Gives: </li></ul></ul><ul><ul><ul><ul><li>Skeleton to cell. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Structure. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Shape. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Movement (Locomotion). </li></ul></ul></ul></ul>Cytoskeleton of of Cytoplasm Maintain Cell Shape & Motility
  76. 77. Cell Has The Ability to Move During Various Conditions <ul><li>Movement Of WBCs During Inflammation (A Natural Defence Reaction of Tissues to Injury). </li></ul><ul><li>Fibroblasts (Connective Tissue Cells) Move to Remodel Damaged Structures During the Process of Wound Healing. </li></ul><ul><li>Movement Of Immunocytes During Immune Response. </li></ul><ul><li>Cells from a Primary Cancer Move Away and Spread to Other Parts of the Body (Cancer Metastasis). </li></ul>
  77. 78. <ul><li>The Cytoskeleton is an Organized Network of Protein Filaments. </li></ul><ul><li>Primary Importance of the Cytoskeleton is in Cell Motility. </li></ul><ul><ul><li>Controls the Location and Movement of the Different Organelles, and of Cell Itself. </li></ul></ul><ul><ul><li>Moves Parts of the Cell in Processes of Growth and Mobility. </li></ul></ul>Cell motility involves physical forces generated by Cytoskeleton
  78. 79. <ul><li>Forms Tracks Along Which </li></ul><ul><li>Cell Organelles Move By </li></ul><ul><li>Contractile Proteins </li></ul><ul><li>Attached to Their Various Surfaces. </li></ul>The Cytoskeleton is Like a Little Highway Infrastructure Inside The Cell.
  79. 80. Other Important Functions Of CYTOSKELETON <ul><li>Give structure, Shape & Support to Cell. </li></ul><ul><li>Helps to Organize many of the Chemical Reactions that Occur in the Cytoplasm. </li></ul><ul><li>Aids Movement of Materials in/out of cells. </li></ul><ul><li>Helps During Endocytosis, the Uptake of External Materials by a Cell. </li></ul><ul><li>Helps Cytokinesis, the Separation of Daughter Cells after Cell Division. </li></ul><ul><li>Helps intracellular transport. </li></ul>
  80. 81. CELL MEMBRANE (Plasma Membrane, Cytomembrane or Plasmalemma) <ul><li>Sheet like structure. </li></ul><ul><li>Encloses the cytoplasm. </li></ul><ul><li>Made up of specific organic compounds. </li></ul><ul><li>Semi-permeable membrane. </li></ul><ul><li>Similar membranes around organelles. </li></ul>
  81. 82. CELL WALL <ul><li>The rigid outermost layer found in plant cell. </li></ul><ul><li>Made up of Cellulose. </li></ul><ul><li>Absent from animal cell. </li></ul>
  82. 83. <ul><li>Membrane-bound, Spherical structure. </li></ul><ul><li>Contains cell's hereditary material. </li></ul><ul><li>Determines & Controls biological behaviour of the cell. </li></ul><ul><li>Components: </li></ul><ul><ul><li>Nucleoplasm. </li></ul></ul><ul><ul><li>Nucleolus. </li></ul></ul><ul><ul><li>Chromatin (Chromosomes + Proteins). </li></ul></ul>NUCLEUS
  83. 84. Nucleus is Responsible For Overall Behavior of the Cell. <ul><li>Biological Behavior is Ultimately Determined by Enzymes & Other Proteins. </li></ul><ul><li>Overall Behavior of cell is Determined by the Ability to Synthesize Specific Types of Proteins & Enzymes. </li></ul><ul><li>Genetic Material Present In Nucleus Determine Type of Proteins Synthesized by Cell and therefore Responsible for the Overall Behavior and Structure of Cell. </li></ul>
  84. 85. Genetic Material is Organized as Chromatin <ul><li>The nucleus contains the cell's genetic material, in the form of multiple linear DNA molecules organized into structures called chromosomes. </li></ul><ul><li>When a cell is &quot;resting&quot; (not dividing) the chromosomes are organized into long entangled structures called chromatin and not into individual chromosomes as we typically think of them. </li></ul>
  85. 86. Chromatin is a DNA-protein complex <ul><li>In chromatin The DNA of a chromosome is associated with proteins, called Histones which organize & compact the DNA. </li></ul><ul><li>During cell division chromatin organizes itself into well defined chromosomes. </li></ul><ul><li>Each chromosome contains a DNA molecule (Having Specific Genes). </li></ul>
  86. 87. CHROMOSOMES <ul><li>Threadlike linear strands of DNA and associated proteins. </li></ul><ul><li>Carries the genes. </li></ul><ul><li>Functions in the transmission of hereditary information. </li></ul>
  87. 88. Each DNA Molecule is Made up of Many Genes <ul><li>Genes are Individual Segments of DNA that Contain the Instructions Needed to Direct the Synthesis of a Protein With a Specific Function. </li></ul>
  88. 89. Genetic Diseases <ul><li>Synthesis of particular enzyme in the cell is controlled by a specific fragment of DNA (Gene). </li></ul><ul><li>Failure of particular fragment results in the deficiency of specific enzyme. </li></ul><ul><li>Results in disorder called genetic diseases. </li></ul>
  89. 90. Examples Of Genetic Diseases <ul><li>Diabetes Mellitus. </li></ul><ul><li>Disorders Of Lipid Metabolism. </li></ul><ul><li>Lipid Storage Diseases. </li></ul><ul><li>Glycogen Storage Diseases. </li></ul><ul><li>Gout. </li></ul><ul><li>PKU. </li></ul><ul><li>Some Types Of Cancers. </li></ul>
  90. 91. NUCLEOLUS <ul><li>Small, round, granular body in the nucleus. </li></ul><ul><li>Composed of protein and RNA. </li></ul><ul><li>Involved in ribosomal RNA synthesis and the formation of ribosomes. </li></ul>
  91. 92. Vacuoles A number of small cavities in the cytoplasm of a cell, bound by a single membrane and containing water, fat, or metabolic waste.
  92. 93. Prokaryotic & Eukaryotic Types on the Basis of Development <ul><li>Prokaryotic. </li></ul><ul><ul><li>Prokaryotes - Missing a Nucleus </li></ul></ul><ul><ul><ul><li>Pro = Pre or Primitive </li></ul></ul></ul><ul><ul><ul><li>Karyotic = Nucleus Bearing </li></ul></ul></ul><ul><li>Eukaryotic. </li></ul><ul><ul><li>Eukaryotes - Having an Organized Nucleus </li></ul></ul><ul><ul><ul><li>eu = True or Good </li></ul></ul></ul><ul><ul><ul><li>Karyotic = Nucleus Bearing </li></ul></ul></ul>
  93. 94. Cell Types On the Basis of Development <ul><li>Eukaryotic. </li></ul><ul><ul><li>Distinct membrane-bound nucleus. </li></ul></ul><ul><ul><li>DNA is organized into chromosomes. </li></ul></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>Protozoa. </li></ul></ul></ul><ul><ul><ul><li>Cells of higher animals and plants. </li></ul></ul></ul><ul><li>Prokaryotic. </li></ul><ul><ul><li>Absence of a nuclear membrane. </li></ul></ul><ul><ul><li>DNA is not organized into chromosomes. </li></ul></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>Bacteria. </li></ul></ul></ul>
  94. 95. Prokaryotic Cell <ul><li>Simple in structure: </li></ul><ul><ul><li>Little or Poor Internal Structural Organisation. </li></ul></ul><ul><ul><li>Poorly Recognizable Organelles. </li></ul></ul><ul><ul><li>An outer cell wall that gives shape. </li></ul></ul><ul><ul><li>Just under the rigid cell wall is the more fluid cell membrane that does not exhibit much structure. </li></ul></ul><ul><li>Nucleus: </li></ul><ul><ul><li>Do not have an organized, well defined nucleus. </li></ul></ul><ul><li>Examples: </li></ul><ul><ul><li>Bacteria, Methanogens and Blue green Algae. </li></ul></ul>
  95. 96. Eukaryotic Cell <ul><li>More complex in structure: </li></ul><ul><ul><li>Well defined Internal Structural Organisation. </li></ul></ul><ul><li>Well defined membrane bound organelles. </li></ul><ul><ul><li>Each organelle has distinctive morphology and perform specific function for the cell. </li></ul></ul><ul><li>Well Organised Nucleus: </li></ul><ul><ul><li>Contained within a membrane, nuclear membrane. </li></ul></ul><ul><ul><li>DNA is organized into chromosomes. </li></ul></ul><ul><li>Examples: </li></ul><ul><ul><li>All the cells of animals and plants. </li></ul></ul><ul><ul><li>A number of unicellular organisms. </li></ul></ul>

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