Respiration Flashcards
(28 cards)
What is glycolysis?
The first stage of respiration which can be both aerobic and anaerobic, turns one 6 carbon glucose into 2 pyruvate (3 carbon), 2 reduced NAD, and 2 ATP.
Where does glycolysis occur?
The cytoplasm
What is the first stage of glycolysis?
Glucose (6 carbon) is changed into hexose biphosphate by surface level phosphorylation, 2 ATP are used.
What is the second stage of glycolysis?
Hexose biphosphate is broken into 2 triose phosphates by a lysis reaction.
What is the third stage of glycolysis?
The triose phosphates are changed into 2 pyruvates required to enter the link reaction in the mitocholdrial matrix. During this stage the oxidation of NAD occurs, and the dephosphorylation of ADP to make reduced NAD and ATP.
What is the link reaction?
When oxygen is available, the end product of glycolysis - pyruvate - will enter the link reaction to produce more ATP.
Where does the link reaction occur?
The mitochondrial matrix
How does pyruvate enter the mitochondrial matrix?
By active transport, the pyruvate requires a small amount of ATP and a transport protein.
What is the first stage of the link reaction?
Pyruvte is oxidised to form acetate and carbon dioxide, this also turns NAD to become reduced into NADH.
What is respiration?
A chemical reaction in the cells which releases ATP (energy) from glucose.
What is the second stage of the link reaction?
Acetate combines with coenzyme A to produce acetyl coenzyme A.
What are the end products of the link reaction?
Acetyl coenzyme A, reduced NAD, and carbon dioxide.
What is the role of coenzyme A?
Coenzyme A binds to the acetate to form acetyl coenzyme A, it also supplies the acetyl CoA to the krebbs cycle to be used in aerobic respiration.
What is a coenzyme?
Coenzymes help enzymes carry out their functions without being used up in the reaction itself.
What is the krebbs cycle?
The krebbs cycle is the third stage of respiration and follows a series of enzyme controlled reactions to produce carbon dioxide, reduced NAD and FADH and ATP from acetyl coenzyme A.
What is the first stage of the krebbs cycle?
The 2 carbon acetyl coenzyme A binds with the 4 carbon oxaloacetate to form 6 carbon citrate which releases coenzyme A.
How is oxaloacetate regenerated?
Through a series of redox reactions. Redox reactions are reactions which involve a transfer of electrons. Redox is both reduction and oxidation takes place.
What is decarboxylation?
A chemical reaction where the carboxyl group is removed and carbon dioxide is produced.
What happens to citrate during the krebs cycle?
Citrate is decarboxylated to produce carbon dioxide and then is then oxidated to produce reduced NAD and FAD.
How is ATP produced during the krebs cycle?
The substrate level phosphorylation of the intermediate transfers a phosphate to ADP.
What is the fourth stage of respiration?
Oxidative phosphorylation
What are the products of oxidative phosphorylation?
Water from oxygen and many ATP molecules.
What is the chemiosmotic theory?
Where does oxidative phosphorylation occur?
The inner mitochondrial membrane.
