Mitochondria, power house of a cell.

MITOCHONDRIA :-

🐣Found in all eukaryotic cells.

🐣Term mitochondria coind by = C. Benda.

🐣Mitochondria = 'energy converting organelle'. 

🐣Sites of aerobic respiration.  

🐣Produce cellular energy in the form of ATP, hence called power house of a cell. 

🐣Mitochondria = double membrane bound organelle. 

🐣Inside mitochondria = its own dsDNA, multiple copies of dsDNA, mitochondrial ribosome,  tRNA, voltage proteins etc. 

🐣Mitochondrial dsDNA = circular &its size = species specific. 

🐣Mitochondrial ribosomes = 55S - 75 S. 

🐣In mitochondria of Tripanosoma brucei  & T. cruzi  = two types of circular DNA. 

1. Maxicircles & 2. Minicircles & both are interlocked into a single massive network & their mitochondrial DNA known as = kinetoplast DNA (KDNA). 

🐣Mitochondria = semi autonomous organelle.

🐣Semi autonomous bcoz = have their own genetic material (DNA), their own ribosome & able to synthesis own proteins.

🐣Mitochondria = dynamic structure,

🐣Dynamic structure bcoz = it frequently dividing, fusing & changing their shape. 

🐣Condition change = it's shape cylindrical to spherical. 

🐣Mitochondria multiply by = binary fission just like bacteria. 

🐣Dynamin - like Drp1/Dmn1 protein aggregates in ring structure around the outer surface of mitochondria, at region where mitochondria will soon divide. 

Evidence to support endosymbiotic theory :- 

🐣M DNA similar to B DNA. 

🐣M ribosome enzymes & transport  system similar to bacteria. 

🐣M & B = approx same size. 

🐣(M = Mitochondria & B = Bacteria) 

🐣Protein synthesis of mitochondria is inhibited by variety of antibiotics.

🐣Antibiotics like, chloramphenicol, tetracycline, erythromycine. 

🐣M inherited = cytoplasmically, nearly uniparental in eukaryotes (from mother). 

MITOCHONDRIAN - RELATED ORGANELLES :-

1. Hydrogenosomes = in Trichomonas vaginalis. 

🐣Trichomonas vaginalis =  a protist, instead of mitochondria it has hydrogenosome.

🐣Hydrogenosome = also a double membrane bound organelle & production of ATP & H.

🐣ATP production via = substrate leval phosphorylation. 

2. Mitosomes = double membrane - bound organelles.

🐣Found in some unicellular anaerobic parasitic eukaryotes, eg., Entamoeba histolytica , Giardia lamblila & microsporidia. 

🐣These unicellular anaerobic parasitic eukaryotes = lack mitochondria & usable to generate ATP. 

🐥In next post i will give you a simple notes about TARGETING OF MITOCHONDRIAL PROTEINS.

Thank you so much student for your interest in science.🙏