respiration Flashcards
(18 cards)
where does glycolysis occur
-in the cytoplasm
what are the 4 stages of respiration
-glycolysis
-link reaction
-Krebs cycle
-oxidative phosphorylation
where does link reaction occur
matrix of the mitochondria
where does the Krebs cycle occur
matrix of mitochondrial
where does oxidative phosphorylation occur
cristae (folds of inner membrane ) of mitochondria
describe the stages in glycolysis briefly
glucose ( 6c)
glucose phosphate
2 x triose phospahte(3c)
2 x pyruvate (3c)
describe the steps in glycolysis completely
1) glucose (6c) is split into 2 carbons
-requires atp
2) this is then turned into glucose phospahte (3c)
3) glucose phospahte then turns into 2 x triose phospahte (3c)
-also needing atp
4)triose phosphate is then converted into 2 x pyruvate
-this reaction actually releases energy by substrate level oxidation
-the triose phospahte is oxidised (oxygen is lost ) and hydrogen is lost , its then met with the co enzyme NAD
hydrogen then is accepted by NAD whihc from reduced NAD
during this reaction ,
6) the pyruvate is then actively transported into the mitochondrion for next stage
what happens if oxygen is not available
anaerobic respiration occurs but the pyruvate remains in the cytoplasm and is converted into other products
what process is glycolysis
anaerobic and occurs in cytoplasm
what type of reaction is the link reaction
-aerobic reaction and occurs in the matrix of the mitochondria
describe the link reaction
-pyruvate is oxidised by the removal of hydrogen atoms
-and co2 is removed
-co enzyme A is added to Acetate ( a 2 carbon mol) to from acetyl coenzyme A
what is the co enzymes in link reaction
co-enzyme A
-NAD
how is pyruvate oxidised in the link reaction
2 hydrogen atoms are removed from pyruvate and are accepted by NAD ( oxidation) to form reduced NAD
-Which forms acetate 2c
-then coenzyme a is added to this to make Acetyl CoA
what is removed also when pyruvate is oxidised
-2 hydrogen atoms
-c02
what is the Krebs cycle
-a series of oxidation -reduction reaction where acetylcoenzye A (2c) combines with with a four carbon molecule , forming a 6c carbon molecule whihc enters the Krebs cycle
-co enzyme A is removed
-the six carbon molecule enters a cycle of reaction resulting in the formation of the 4c molecule
what reaction occur in the Krebs cycle
-removal of hydrogen atoms
-removal of c02
what happens with the hydrogen atoms that are removed during the Krebs cycle
-passed to the coenzymes NAD and FAD forming reduced NAD and reduced FAD
-these reduced coenzymes pass the hydrogen atoms to the electron transport chain producing ATP via oxidative phosphorylation
-additionly each cycle produces one ATP molecule via substrate level phosphorylation ( a reaction releasing energy for ATP production )
-the link reaction and Krebs cycle occur twice per glucose molecule as two pyruvate molecules are produced in glycosides
