Saran's Learn Microbiology

  CHLOROPLAST ·     Plastids are Cytoplasmic organelles of Photosynthetic protists and Plants that often possess pigments such as Chlorophylls and Carotenoids, and are the sites of synthesis and storage of food reserves. The most important type of plastid is the Chloroplast. ·       Chloroplasts (Greek  “chloros” , meaning “green” and  “plast” , meaning “form” or “entity”) are Light harvestings structures present in Algae and Plants and it is the site of Photosynthesis. ·        Chloroplast is an organelle that contains the Photosynthetic pigment Chlorophyll. ·      The size of the Chloroplast usually varies between 4 - 6 µm in diameter and 1 - 3 µm in thickness. ·        Chloroplasts are Oval or Biconvex in shape. ·        Chloroplasts are relatively large and readily visible with the Light microscope, and their number per cell varies among species. ·        Like Mitochondria and the Nucleus, Chloroplasts have two Phospholipid bilayer membranes and DNA. ·       Althoug

  HYDROGENOSOMES ·      Mitochondria typically respire oxygen and possess a small DNA genome. But among various groups of Anaerobic Eukaryotes, typical Mitochondria are often lacking, organelles called Hydrogenosomes being found instead. ·        Hydrogenosomes are approximately 1 to 2 micrometers in size. ·       Hydrogenosomes were first described in the flagellate  Tritrichomonas foetus  by Lindmark and Muller (1973)  as sub-cellular compartments that produce Hydrogen and ATP. Since then, these organelles have been described in a number of different unicellular eukaryotes adapted to microaerobic or anoxic environments. ·       Like Mitochondria, Hydrogenosomes are surrounded by a double membrane, produce ATP and sometimes even have Cristae. ·    In contrast to Mitochondria, Hydrogenosomes produce molecular Hydrogen through fermentations, lack Cytochromes and usually lack DNA.   Biochemistry of Hydrogenosomes ·     The major biochemical reaction in the Hydrogenosomes is

  MITOCHONDRIA ·        The mitochondria ( Greek . “mitos” - thread; “chondros” - granule) are the centres for the Cellular respiration and Energy metabolism. ·        Mitochondria was first described by a German Pathologist named Richard Altmann in 1890. ·        Mitochondria are regarded as the “Power houses of the cell”. ·     Mitochondria are rod-like or filamentous bodies. It is present in eukaryotes and absent in prokaryotes. ·        The Eukaryotic cells contains 800 to 2500 Mitochondria per cell. ·        The size of the mitochondria is 0.2 to 0.8 µm in diameter and 0.5 to 1.0 µm in length. ·        The shape of the mitochondria in Non – static. ·        Major function of Mitochondria ATP Generation through Electron Transport Chain (ETC). ·        Mitochondria consist of 5 important parts. They are a)      Outer Mitochondrial Membrane b)      Inner Mitochondrial Membrane c)      Inter Membrane Space d)      Cristae e)      Matrix