Electron transport chain

• What is the final common pathway for coenzymes NADH and FADH2?

  Electron Transport Chain (ETC)
• What do reduced coenzymes donate to the electron carriers in the ETC?

  A pair of electrons
• What happens to electrons as they pass down the ETC?

  They lose energy and generate ATP
• What is the role of the proton gradient in ATP synthesis?

  It drives ATP synthesis through ATP synthase
• Where does glycolysis take place?

  Cytoplasm
• What is the inner mitochondrial membrane's permeability status?

  Impermeable to most ions and molecules
• What is the function of substrate shuttles in mitochondria?

  Permit passage of specific molecules to the matrix
• How are electrons from cytosolic NADH transported into mitochondria?

  By shuttle systems to mitochondrial NAD+ or FAD
• What are the components of the respiratory chain?

  NADH, Coenzyme Q, Cytochrome C, Molecular O2
• What is the role of Complex I in the ETC?

  Catalyzes transfer of electrons from NADH to CoQ
• What does Complex II do in the ETC?

  Transfers electrons from succinate to CoQ
• What is the function of Complex III in the ETC?

  Transfers electrons from ubiquinol to cytochrome C
• What is the role of Complex IV in the ETC?

  Transfers electrons from cytochrome C to O2
• What is the relationship between electron transport and proton pumping?

  Energy released pumps protons across the membrane
• What is oxidative phosphorylation?

  Process where electrons generate ATP via ETC
• What does the chemiosmotic hypothesis describe?

  ATP generation from electron transport and proton gradient
• What is the significance of the proton motive force?

  It drives ATP synthesis through ATP synthase
• How many ATP are produced from one NADH?

  3 ATP
• How many ATP are produced from one FADH2?

  2 ATP
• What is the effect of uncoupling proteins in mitochondria?

  Create a proton leak and release heat
• What is the role of thermogenin in brown adipose tissue?

  Responsible for heat production
• What happens during an overdose of synthetic uncouplers?

  No ATP synthesis; energy released as heat
• What is kernicterus?

  A neurological disorder from high bilirubin levels
• What are mitochondrial diseases related to?

  Defects in oxidative phosphorylation due to mutations
• What is Leber hereditary optic neuropathy?

  Point mutations in mitochondrial ETC components
• What is the impact of riboflavin deficiency?

  Affects Complex I and II of the ETC
• What is the effect of cyanide on the ETC?

  Inhibits Complex IV by competing with O2
• What vitamins are coenzymes for the ETC?

  NAD from Niacin (B3) and FAD from Riboflavin (B2)
• What are the symptoms of vitamin deficiencies affecting the ETC?

  Severe lethargy and fatigue
• What complications can arise from ETC-related vitamin deficiencies?

  Affects cardiovascular, nervous, muscular systems
• What is the role of ATP synthase in ATP production?

  It synthesizes ATP from ADP and Pi using proton gradient
• What are the specific functions of each complex in the ETC?

  Each complex transfers electrons and pumps protons
• What are the differences between NADH and FADH2 in ATP yield?

  NADH yields 3 ATP, FADH2 yields 2 ATP
• What are the mechanisms of synthetic uncouplers?

  They increase permeability of the inner mitochondrial membrane
• How do mitochondrial diseases relate to energy demand in tissues?

  They affect tissues with high energy demand like heart and brain
• What is the significance of heteroplasmy in mitochondrial inheritance?

  It affects the severity of mitochondrial diseases
• How do mutations in mitochondrial tRNA affect oxidative phosphorylation?

  They impair protein synthesis for ETC components
• What is the role of specific metal ions in the ETC complexes?

  They act as electron carriers in the complexes
• What is the importance of proton channels in ATP synthase function?

  They allow protons to flow back into the matrix, driving ATP synthesis