Respiration Flashcards
Metabolism
All chemical reactions that take place in a cell
Glycolysis
Splitting of 6-carbon glucose into two 3-carbon pyruvate
Describe the process of glycolysis
- substrate level phosphorylation of glucose using 2 ATP to raise to higher energy
- phosphorylated glucose splits into two triose phosphate
- triose phosphate is oxidised by removing hydrogen to produce NADH
- releases some energy to phosphorylate ADP to ATP
State where glycolysis occurs
cytoplasm
State the products of glycolysis per glycose
- 4 ATP (net ATP 2)
- 2 NADH
Suggest how red blood cells (which have no mitochondria) produce ATP
- anaerobic respiration
- glycolysis in cytoplasm produces ATP
Link Reaction
Production of 2-carbon acetyl coenzyme A from 3-carbon pyruvate
Describe the process of link reaction
- decarboxylation of pyruvate by losing CO2
- 2-carbon compound loses hydrogen by oxidation
- reduced NAD and 2-carbon acetate formed
- acetate combines with coA to form acetyl coA
Suggest how pyruvate enters the mitochondria
active transport
State where link reaction and Kreb’s cycle occur
mitochondrial matrix
Kreb’s Cycle
- acetyl coA combines with 4-carbon oxaloacetate from previous cycle
- forms 6-carbon citrate
- decarboxylation and oxidation of citrate forms NADH and 5-carbon sugar
- decarboxylation and oxidation of 5-carbon sugar forms 2 NADH and FADH2
- oxaloacetate reformed
- some energy released for substrate level phosphorylation of ADP to ATP
State products of Kreb’s cycle per glucose
Kreb’s cycle occurs twice
- 2 ATP
- 4 CO2
- 6 NADH
- 2 FADH2
Suggest reasons Kreb’s cycle is significant
- source of intermediate compounds required to manufacture fatty acids, amino acids etc.
- provides hydrogen atoms carried by coenzymes NAD and FAD for oxidative phosphorylation = ATP
- regenerates 4-carbon oxaloacetate
Suggest how hydrogen atoms carried by coenzymes NAD and FAD are used to release energy
- electrons travel along e- transport chain and H+ pumped across to intermembramal space
- provides energy for oxidative phosphorylation
- produces ATP
State where oxidative phosphorylation occurs
cristae