mitochondriait is the power house of the cell

Question

MITOCHONDRIA

1. It is the power house of the cell because they are the major centers of release of energy in the aerobic respiration.
2. Mitochondria and chloroplast both are antagonistic to each other. Chloroplast stores food stuffs energy during photosynthesis whereas mitochondria convert potential energy of food stuffs into kinetic energy during respiration.
3. Discovered by Kolliker (1880) in striped muscles of insects and he called it Cytoplasmic granules .
4. Flemming called it Fila.
5. Petzium called them Sarcosome.
6. Richard Altman called it Bioplast.
7. The term "mitochondria" given by Benda.
8. F. Meves first observed them in plants ( Nymphea)
9. Kinsbury and Hogeboom related them with cell respiration.
10. Seekevitz called them power house of cell.
11. Palade worked out ultrastructure of mitochondria.
12. Nass-Nass, Afzelius and Margit discovered DNA in mitochondria & called it mtDNA. It is also known as orgenelle DNA.
13. Mitochondria can be stand by stained by Janus Green-B. After staining mitochondria seems Greenish blue.
14. Total mitochondria in a cell = Chondriosome, term given by Ptezium.
15. Life span of mitochondria is 5-10 days.

NUMBER

1. Average number of mitochondria in each cell is about 1000-1600.
2. Single mitochondrion present in Microasterias (alga), Chlorella fusca (Green algae), Trypanosoma, Micromonas (Protozoans).
3. Less than 10 mitochondria present in Fungi.
4. 25 in sperm cell, 300-500 in kidney cells, 500-1000 in liver cells, 30000 in some oocyte, 50000 in giant amoeba (chaos chaos) & 5 lakhs in flight muscle cells.

SHAPE & SIZE

1. Mitochondria are spherical or filamentous in shape.
2. Smallest mitochondria are present in yeast (< 1m).
3. Largest mitochondria are present in Rana pipens ( 20-40 m)
4. In human body largest mitochondria are present in pancreatic cells (10m).
5. Size depends on activity of cell. Active cells (meristematic cells) have large mitochondria.