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Bacteria, Types, Harmful and beneficial relation with human

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  1. 1. Life Saving College Of Nursing M. Farooq Marwat RN, Dip. Card, BSN
  2. 2. Objective  At the end of this presentation, the student will be able to :  Understand the bacteria  Know about the characteristics of bacteria  Know about the classification of bacteria  Know about the structure of bacteria  Know about the disease cause by bacteria
  3. 3. Bacteria  The word bacteria is derived from a Latin and a Greek word Bakteria meaning “cane”. (Rod)  Bacteria is a micro organism with few micro meter in length and have wide range of shapes (round, oval, rod and spiral shapes).  First discover by Antony Van Leeun Hook in 1676, initially called “Animalcules”  Study about bacteria is know as “Bacteriology”, while study about the harmful effect of bacteria on human body is known as “Medical bacteriology”.
  4. 4. Bacteria  Bacteria are found everywhere on earth i.e. in soil, water, air, deep earth crust, radio active waste and acidic hot spring  A single gram of soil contain 40 million bacteria while a million bacteria found in an ml of fresh water.  However only few of these are harm full to human body causes disease  They produce more Oxygen than plants
  5. 5. Bacteria  Bacteria are earlier form of life form on earth.  Their fossils are found 2.5 billions years ago
  6. 6. Characteristics of Bacteria  Size of bacteria rang between 0.5 to 5 micrometer  They are prokaryotic microbes (have no membrane bounded Nucleus and mitochondria)  Have a single chromosome as Genetic material  Enclosed in a rigid cell wall made up of peptidoglycane  Some bacteria, along with plasma membrane, contain an additional membrane called Capsule
  7. 7. Characteristics of Bacteria…..  Reproduce by Amitosis (asexual form of reproduction)  Many bacteria form Spores  Some bacteria are Auto tropes while some are hetro tropes  Most grow best at pH of 6.5 to 7.0  Many act as decomposers recycling nutrients
  8. 8. Nutrition Source for bacteria  Saprobes – feed on dead organic matter  Parasites feed on a host cell  Photoautotroph use sunlight to make food  Chemoautotroph oxidize inorganic matter such as iron or sulfur to make food
  9. 9. Classification of bacteria Bacteria are classified according to following properties 1. According to Morphology 2. According to Needs for Oxygen 3. According to Staining they retain 4. According to Heat Tolerance 5. According to Pathoginicity
  10. 10. According to Morphology  According to morphology (shape), Bacteria are classified into  Cocci  Those who appear in Round or oval shape  Bacilli  Those who appear in Rod shape  Spirillia  Those who appear in spring spiral or shape
  11. 11. According to Morphology…
  12. 12. Arrangement of Bacteria  Diplococci  Arrange in pairs  Stephylo cocci  Arrange in cluster  Strepto cocci  Chain like arrangement
  13. 13. According to Needs for Oxygen  According to their need for oxygen, Bacteria are classified into  Aerobic  Those who required Oxygen to live  Anaerobic  Those who don’t required Oxygen to live  Facultative Aerobic  Those who can adjust in either presence or absence of Oxygen
  14. 14. According to Staining they retain  According to stain (color) they retain or appear during the procedure of gram staining, Bacteria are classified into  Gram Positive  Those who appear blue, purple or violate in color  Gram Negative  Those who appear red or pink in color
  15. 15. Gram + Gram -
  16. 16. According to Heat Tolerance  According to temperature on which Bacteria can be best live, they are classified into  Psychrophilic bacteria  Can survive on extreme cold temperature  Mesophilic bacteria  Can survive on extreme cold temperature  Thermophilc bacteria  Can survive on extreme hot temperature
  17. 17. According to Pathoginicity According to disease causing ability of bacteria, they are of two types  Pathogenic bacteria  Those who cause disease in human  Non-Pathogenic bacteria  Those who cannot cause disease in humans
  18. 18. Structure of Bacteria
  19. 19. Structure of Bacteria •Capsule •Cell wall •Ribosomes •Nucleoid •Flagella •Pilli •Cytoplasm
  20. 20. Capsule keeps the cell from drying out and helps it stick to food or other cells
  21. 21. Cell Wall Thick outer covering that maintains the overall shape of the bacterial cell
  22. 22. Ribosomes  cell part where proteins  are made  Ribosomes give the  cytoplasm of bacteria a  granular appearance in  electron micrographs
  23. 23. Chromosome A ring made up of DNA Bacteria contain a single chromosome
  24. 24. Flagella A whip-like tail that some bacteria have for locomotion
  25. 25. Bacteria Reproduction  Under optimum conditions bacteria can reproduce every 20 minutes. (double every 10 to 20 minutes.  Bacteria reproduction is controlled by various factors including : temperature and food availability.  Their reproduction can be by:  Asexual: Binary fission  Sexual: conjugation
  26. 26. Binary Fission • It involves the copying of the DNA and the splitting into two new cells.
  27. 27. Conjugation • Sexual reproduction • One bacteria is able to transfer its DNA into another bacteria by means of a pilus (pili)
  28. 28. Beneficence of Bacteria  Makes cheese, yogurt, buttermilk and pickles  Produces vitamins in your intestine  Helps in digestion of insoluble fibers  In industry, bacteria are important in sewage treatment and the breakdown of oil spills, the recovery of gold, copper and other metals in the mining sector,
  29. 29. Beneficence of Bacteria  Bacteria are also helpful in biotechnology, and the manufacture of antibiotics and other chemicals.  Many act as decomposers recycling nutrients  Actinomycetes, produce antibiotics such as streptomycin and nocardicin.  Saprobes help to break down dead organic matter.
  30. 30. Harmful effect of Bacteria  Cause disease in body including: 1. TB 2. Pertusis 3. Diphtheria 4. Tetanus 5. Dysentery 6. Typhoid 7. Meningitis, Encephalitis 8. Gonorrhea 9. Pneumonia 10. Syphilis
  31. 31. Endospores  Some bacteria are capable to produce spore that are highly resistant to extreme environmental condition.  In favorable condition, bacteria re grow again to a bacteria
  32. 32. Toxins  Some bacteria release poisons known as toxins which cause food poisoning. Some toxins, known as exotoxins multiply in food. These toxins are not easily destroyed by cooking and may remain in food once they have developed.  Other bacteria produce toxins inside the human body only after the food has been eaten. These are called endotoxins