(S5)C12- Respiration Flashcards
name the 4 stages of aerobic respiration
Glycolysis, link reaction, Krebs cycle, oxidative phosphorylation
Where does glycolysis take place
cytoplasm
Where does the link reaction take place
matrix (mitochondria)
Where does the krebs cycle take place
matrix
Where does oxidative phosphorylation occur
cristae
In glycolysis how many ATP molecules are invested at the start
2 ATP molecules
What are the products of glycolysis
2x NADH and ATP
2x pyruvate
describe the process of glycolysis
1) glucose phosphorylated by two ATP molecules that were invested
2) Phosphate is released from the breakdown of ATP this cause the glucose molecule to become unstable
3) As it is unstable it breaks in half to form triose phosphate
4) triose phosphate is then dehydrogenated by NAD so NAD becomes NADH
5) The release of this hydrogen bond releases enough energy to form 2 ATP molecules
6) triose phosphate become pyruvate
By which process does pyruvate move into the matrix after glycolysis
active transport
Describe the process of the link reaction
1) pyruvate moves from the cytoplasm to the matrix via active transport
2) The pyruvate is then decarboxylated (CO2 removed) and oxidised (Loss of H+ to NAD) to form Acetate
3) Acetate then combines with Coenzyme A to form Acetyle Coenzyme A
What are the products of the link reaction
2x acteyl CoA, CO2, NADH
describe the process of the krebs cycle
1) Oxaloacetate binds with acetate CoA
2) cause CoA to dissociate from the acetate
3) This forms citrate
4) the citrate is then decarboxylated twice to make a 4 carbon compound
5)the 4 carbon compound is then reformed back to oxaloacetate releasing energy when the hydrogen was given off
6) the energy is then used for the formation of ATP
7) any hydrogens left during the process are accpeted by NAD and FAD
What are the products of the krebs cycle
2 CoA, 2 Oxaloacetate, 4 CO2, 2 ATP, 6 NADH
Describe the process of oxidative phosphorylation
1) when the FADH and NADH are in the cristae they bind to the proteins and dissociate their hydrogen atoms
2)The proteins then encourage these hydrogen atoms to split into electrons (e-) and protons (H+).
3) The electrons then pass along the electron transport chain
4) as they travel they release energy for the protons to be pumped across the carrier proteins to the inter-membrane
5) Electrochemical gradient of protons (High concentration in the inter membrane)
6) As a result the protons travel through ATP synthase via facilitated diffusion
7) This process releases energy that can be used to catalyse the resynthesis of ATP
8) Oxygen final electron acceptor and picks up hydrogen to form water (H20)
What is the role of Oxygen in oxidative phosphorylation
Final electron acceptor
If it didn’t accept the electron:
-then they would build up and no more elctrons will be accpetd into the electron transport chain
-meaning that hydrogen cannot move across the membrane
-no electrochemical gradient
-ATP cannot be created
