Anatomy 25 organelles lysosomes

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Anatomy 25 organelles lysosomes
2012-01-26 04:43:05
anatomy 25 cytology organelles lysosomes

anatomy 25 cytology organelles lysosomes
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  1. Organelles
    Lysosomes translates from latin to mean "break body", they are little sacs of acid hydrolases ( digestive enzymes ) which break down various things in the cell or outside which need broken down.

    Acid hydrolases are encased in unit memrane at the trans-Golgi-network and sent out as a lysosome.

    Peptide bonds between amino acids in a protein are formed by removing H from one amino and OH from another amino and hooking the two together at the snipped off parts. Acid hydrolases add the H2O back in to break this bond and break the protein down.

    A primary lysosome is a lysosome that is not yet activated, it has not yet attached and begun breaking down material.
  2. Organelles
    The process of a lysosome attaching to and breaking down something else is called "Heterophagy", meaning "other eating".

    Material to be digested is "endocytosed", brought into the cell via phagosome ( phagocytosis ), pinocytotic vesicles ( pinocytoses ) or coated vesicle ( receptor mediated endocytosis ).

    The coated vesicle merges with the lysosome, forming a secondary lysosome.

    The contents of the secondary lysosome are acidified and the lysosome membrane pumps hydrogen ions into the coated vesicle or phagosome and its contents are digested.

    Useful materials are ( released into cytoplasm?, transported to other parts of the cel? ) and waste material is encased in unit membrane and excreted or stored...?
  3. Organelles
    Autophagy means "self eating".

    Cell material or structure in cell is tagged with a "kill signal", ubiquitin. The offending material is encased in unit membrane from rer to form an auotophagic vacuole.

    A lysosome bonds to the autophagic vacuole forming a secondary lysosome.

    The rest of the process is like heterophagy - contents of lysosome become acidc, hydrogen ions are pumped into vacuole, material in vacuole is broken down.