Mitochondria ByDr P B Sirsat Assist Professor in
Mitochondria By-Dr. P. B. Sirsat Assist. Professor in Zoology, B. Sc. F. Y.
Mitochondria • The mitochondria are found in plant and animal cells. • Mitochondria are bounded by a double membrane surrounding fluid-filled matrix. 3 -2
• The mitochondria are found in plant and animal cells. • Mitochondria are bounded by a double membrane surrounding fluid-filled matrix. 3 -3
Organelles and evolution • Both chloroplasts and mitochondria are double membrane bound • They involved in energy reactions • They contain extranuclear DNA and characteristic small ribosomes of their own • This has led biologists to believe that there may be some similarity in their origins in the cells of eukaryotes. • The endosymbiotic theory
MITOCHONDRION • The inner membrane contains the enzyme necessary for the synthesis of Adenosine Triphosphate (ATP) • The mitochondria are closely associated with the pathways of respiration • These metabolic pathways are divided up and supported by the membranes
• The inner membranes of mitochondria are cristae. • The matrix contains enzymes that break down carbohydrates and the cristae house protein complexes that produce ATP. 3 -6
• The mitochondrial matrix contains lipids, protein, circular DNA and 70 -S ribosomes. • The mitochondrial crestae shows a layers of protein molecules and lipid molecules. • The creaste also shows respiratory chain enzymes and F 1 particles called alimentary particles. FUNCTIONS OF MITOCHONDRIA • It performs function such as oxidation, oxidative photophosporylation and respiratory chain enzymes. • It is actually respiratory organ of cells where the food stuff i. e. carbohydrate, fat are complementary, oxidize in to the CO 2 and H 2 O & large amount of energy is released which is utilized by mitochondria for the synthesis ATP. Therefore mitochondria is known as ‘powerhouse of cell’. REACTION: A-P~P~P ------ ADP+Pi+7000 Cal.
Mitochondrial Structure (cont. )
Mitochondrial Structure
Mitochondrial Structure (cont. ) SUBSARCOLEMMAL MITOCHONDRIA MODELED CAPILLARY INTERFIBRILLAR MITOCHONDRIA
MITOCHONDRION (pl. mitochondria) Cristae Inter membrane space Mitochond rial envelope outer membran e inner membra ne 1. 0 to 12. 5 µm Inner matrix
MITOCHONDRION (gk mitos = thread khondrion = granule) TEM of mitochondrion from mouse kidney cell
Mitochondrion structure 3 -14
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