respiration Flashcards
define respiration
the process whereby organic molecules are oxidised to release chemical potential energy for the synthesis of ATP
what are the 2 methods of ATP synthesis?
substrate-level phosphorylation and oxidative phosphorylation
function of coenzymes NAD+ and FAD+
act as electron acceptors and donors that transfer electrons from substrates to ETC
what is the structure-function relationship of the inner mitochondrial membrane?
the inner mitochondrial membrane is extensively folded into cristae projecting inwards towards the matrix=> providing a large surface area for the attachment of electron carriers, enzymes and ATP synthase
site of accumulation of H+
intermembrane space
direction of diffusion of H+
from intermembrane space to the matrix
site of glycolysis
cytosol
outline the process of glycolysis
- phosphorylation of hexose
->glucose is phosphorylated by ATP into glucose-6-phosphate
->glucose-6-phosphate is converted into fructose-6-phosphate
->fructose-6-phosphate is phosphorylated by ATP into fructose-1,6-bisphosphate - cleavage of 6C sugar bisphosphate
->fructose-1,6-bisphosphate is cleaved into 2 triose phosphate molecules (3C)
3.triose phosphates are converted into pyruvate
->oxidation occurs and 2 NADH are synthesized
->substrate-level phosphorylation also occurs producing 4 ATP
-> net 2 ATP produced
requirements for glycolysis (reactants)
1 glucose, 4 ADP, 2 NAD+
products of glycolysis
2 pyruvate, 2 ATP, 2 NADH
name the enzyme which catlayzes the phosphorylation of glucose into glucose-6-phosphate
hexokinase
hexokinase is allosterically inhibited by…
its product glucose-6-phosphate
name the enzyme which catalyzes the phosphorylation of fructose-6-phosphate into fructose-1,6-bisphosphate
phosphofructokinase (PFK1)
PFK1 is allosterically inhibited by…
ATP
outline the process of link reaction
1.pyruvate is decarboxylated releasing one CO2 this is catalysed by pyruvate decarboxylase
2. NAD+ is reduced to NADH
3. the remaining 2C compound combines with coenzyme A to form acetyl-CoA