Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
21 Cards in this Set
- Front
- Back
|
Role of the outer mitochondrial membrane |
Separates cell contents from the outside environment |
|
|
Role of the mitochondrial intermembrane space |
Location for oxidative phosphorylation to occur |
|
|
Role of mitochondrial inner membrane (cristae) |
Provides large amount of surface area for many reactions to occur |
|
|
Role of mitochondrial matrix |
Contains enzymes to catalyse important metabolic reactions |
|
|
Stages of glycolysis |
Energy investment - glucose phosphorylised to hexose biphosphate (2 ATP needed) Cleavage - hexose biphosphate split into 2 triode phosphate molecules Energy generation - triose phosphate molecules oxidised further to pyruvate (4 ATP produced) |
|
|
What happens to the 2 reduced NAD produced from glycolysis? |
Used to further generate more ATP in oxidative phosphorylation later (under aerobic conditions) |
|
|
Describe the link reaction |
Pyruvate actively transpired into mitochondrial matrix
Pyruvate is dehydrogenated and decarboxylised to form acetate
Acetate combined with Coenzyme A to form Acetyl CoA |
|
|
Krebs cycle |
FIND OUT |
|
|
Define oxidative phosphorylation |
Synthesis of ATP from ATP and Pi in the presence of oxygen |
|
|
Describe oxidative phosphorylation |
Hydrogen atoms from reduced NAD/reduced FAD are split into H+ and E- Electron passes along ETC to oxygen (the final electron acceptor) Energy lost by electrons is used to pump protons across membrane into intermembrane space Proton concentration gradient established across inner mitochondrial membrane Protons diffuse back into matrix down electrochemical gradient through transmembrane protein channel associated with ATP synthase Proton motive force drives ATP formation (catalysed by ATP synthase) known as chemiosmosis |
|
|
Overall ATP yield in aerobic respiration |
Total = 32 (ish) Some energy lost as heat to maintain body temperature for enzyme catalysed reactions Some energy lost as heat to maintain body temperature for enzyme catalysed reactions
|
|
|
State 2 processes that occur in the absence of oxygen |
Lactate fermentation (mammals) Ethanol fermentation (yeast) |
|
|
Summarise lactate fermentation |
Hydrogen atoms from reduced NAD are donated to pyruvate (form glycolysis), reducing pyruvate to lactate and regenerating reduced NAD back to NAD |
|
|
Summarise ethanol fermentation |
Pyruvate is decarboxylated to produce CO2 and ethanal (catalysed by pyruvate decarboxylase) Hydrogen atoms from reduced NAD are donated to ethanal, reducing ethanal to ethanol and regenerating reduced NAD back to NAD |
|
|
ATP yield comparison between anaerobic and aerobic respiration |
Aerobic respiration produces much more ATP as pyruvate enters the link reaction and krebs cycle allowing oxidative phosphorylation to take place (producing a larger amount of ATP) |
|
|
Cause of muscle fatigue in mammals |
Build up of lactate Hydrogen ions associated with lactate lower pH and may denature enzymes (changing charge distribution of active site) or other proteins (breaking hydrogen/ionic bonds) |
|
|
Respiritory substrates and when they can be respired |
Carbohydrates - aerobic and anaerobic
Lipids - anaerobic only
Proteins - anaerobic only (only extreme situations i.e. starvation) |
|
|
Typical RQ values |
Carbohydrates = 1.0
Lipids = 0.7
Protein = 0.9 |
|
|
Decarboxylation |
The removal of a carbon atom as carbon dioxide |
|
|
Phosphorylation |
The transfer of a phosphate group to an organic molecule |
|
|
Dehydrogenation |
The removal of a hydrogen atom from a substrate molecule |
