Mit: Oxidative phosphorylation → ATP Chl: Photosynthesis → ATP +a and oxidative phosphorylation A. Mitochondrial structure and function
Intermembrane space: Contains several enzymes use ATP to phosphorylate other nucleotides. Matrix: Enzymes; Mit DNA, Ribosomes, etc.
B. Specific functions localized within the Mit by disruption of the organelle and fractionation
Matrix Pyruvate oxidation TCA cycle ßoxidation of fats
Electron transport Oxidative phosphorylation Metabolite transport
Intermembrane space Nucleotide phosphorylation
Outer membrane: Contains channel-forming protein, called Porin. Permeable to all molecules of 5000 daltons or less. Inner membrane (Impermeability):
Contains proteins with three types of functions:
Localization of metabolic functions within the mitochondrion
Outer membrane: Inner membrane:
Phospholipid synthesis fatty acid desaturation Fatty acid elongation
Figure 7-5 Localization of mitochondria near sites of high ATP utilization in cardiac muscle and a sperm tail.
Inner and outer mitochondrial membranes enclose two spaces: the matrix and intermembrane space.
The size and number of mitochondria reflect the energy requirements of the cell.
Figure 7-4 Relationship between mitochondria and microtubules.
Figure 7-3 Mitochondrial plasticity. Rapid changes of shape are observed when a mitochondrion is visualized in a living cell.
DNA replication, RNA transcription, Protein translation
Chapter 7
Energy Generation in Mitochondria and Chloroplasts
(1) Mitochondria: in all eukaryotic cells The relationship between the structure and function of mit. (2) Chloroplasts: in plant cells The relationship between the structure and function of chl.
(1) Electron-transport chain: Carry out oxidation reactions; (2) ATP synthase: Makes ATP in the matrix; (3) Transport proteins: Allow the passage of metabolites
Figure 14-6 Fractionation of purified mitochondria into separate components. These techniques have made
it possible to study the different proteins in each mitochondrial compartment. The method shown, which allows the processing of large numbers of mitochondria at the same time, takes advantage of the fact that in media of low osmotic strength water flows into mitochondria and greatly expands the matrix space (yellow). While the cristae of the inner membrane allow it to unfold to accommodate the expansion, the outer membranewhich has no folds to begin withbreaks, releasing a structure composed of only the inner membrane and the matrix.