LYSOSOMES

Like mitochondrial lysosomes are also  typical membrane bound and dense  fluid filled sac  like cytoplasmic  organelles  of all eukaryotic cells these  however, different  from mitochondria  in their   smaller size  0.08to0.8 in diameter  and typically  spheroidal  ellipsoidal or ovoid shape having  a single   limiting  in units membrane  and containing only  hydrolytic enzymes  in their watery  ,matrix, These  were first  observed and isolated by Nobel  laureate de duve 1949 and named , lysosomes  by him  and novikoff in 1955 .

These  organelles arise as primary  lysosomes  from diastalcisterna  at  the maturing   at the maturing face  of Golgi  complex   units. Each  primary lysosome is known to contain 40to50 hydrolytic enzyme  in an acidic medium,  the protein back bones of these  enzyme are synthesize  by ribosomes, accumulate and glycosylated  conjugated  to carbohydrates  in  endoplasmic  reticulum  and then  transferred  to Golgi  complex  through  transitional vesicles  in the cisternae of Golgi  complex .these  enzyme  are sorted  out and ultimately  packaged  into  primary lysosomes.

Functions of lysosomes: Intracellular  and extracellular  digestion of most biological substance is the sole  function  of lysosomes These are -

1.      Digest liquid  or silid  materials taken  in by cells from extracellular medium  respectively by pinocytosis  and phagocytises  .

2.      Bring  about  breakdown  of organic materials  outside  the cells when poured  out in  extracellular  medium by the  saprozoic  organisms and

3.      Digest worn  out  or unnecessary  parts of the cells or even whole cells by the so called  process of autophagy.