respiration Flashcards
Role of the mitochondria
To release energy in the aerobic phase of respiration. The energy is used to form ATP.
Matrix
Contains enzymes which carry out the citric acid cycle
Inner membrane
Many folds for a large surface area. The carrier proteins of the electron transport chain are here
Making and breaking down ATP
ATP is a high energy molecule. It is used to transfer energy requiring reaction in the cell.
ATP is the link between the breakdown of glucose and releasing its energy (respiration reactions) and having energy to do cell work
Phosphorylation
Phosphorylation means adding a phosphate to a molecule.
As ATP is converted to ADP, its third phosphate binds to glucose or intermediates during glycolysis. The molecule has become PHOSPHORYLATED
The role of the dehydrogenase enzyme
Dehydrogenase enzymes REMOVE hydrogen ion and electrons and pass them to the coenzyme NAD forming NADH
This occurs in both glycolysis and in the citric acid cycle
The role of the dehydrogenase enzyme
Dehydrogenase enzymes REMOVE hydrogen ion and electrons and pass them to the coenzyme NAD forming NADH
This occurs in both glycolysis and in the citric acid cycle
Glycolysis
Glycolysis is the breakdown of glucose to pyruvate in the cytoplasm
Energy investment phase : ATP is required for the phosphorylation of intermediates
Energy pay off phase : During this stage, more ATP is generated than use (4 ATP) resulting in a net gain of 2 ATP
Citric Acid Cycle
In the matrix of the mitochondria and only in the presence of oxygen. Pyruvate is broken down to acetylcholine. This combines with coenzyme A to form acetyl coenzyme A. The acetyl group acetyl coenzyme A enters the citric acid cycle by combining with oxaloacetate to form citrate. During a series for enzyme controlled steps, citrate is gradually converted back to oxaloacetate which results in the generation of ATP and release of CO2 . The hydrogen ions and electrons from NADH are passed to the electron transport chain on the inner mitochondrial membrane
