TERMINAL RES-BI25M7 Flashcards
What is the primary function of the electron transport chain?
To pass high-energy electrons from NADH and FADH2 to oxygen, forming water and producing ATP.
What are the high-energy electron carriers mentioned?
- NADH
- FADH2
What process allows the production of ATP via oxidative phosphorylation?
The coupling of the oxidation of carbon fuels to ATP synthesis through the electron transport chain.
What is the role of mitochondria in cellular respiration?
The only site of oxidative phosphorylation in eukaryotes.
What are the two main components of ATP synthase?
- F0 – membrane bound proton conducting unit
- F1 – catalytic unit for ATP synthesis
What does the glycerol phosphate shuttle do?
Transfers reducing equivalents from cytoplasmic NADH to FADH2 in the mitochondria.
Which complex in the electron transport chain oxidizes NADH?
Complex I: NADH-Q oxidoreductase.
What is the main consequence of using FADH2 instead of NADH in the electron transport chain?
Less ATP is generated when FADH2 is oxidized compared to NADH.
Fill in the blank: The process of moving protons across the inner mitochondrial membrane creates a _______.
proton gradient.
What is the stoichiometry of ATP production from NADH and FADH2?
- Approximately 2.5 mol of ATP per mol of NADH
- Approximately 1.5 mol of ATP per mol of FADH2
What happens during uncoupling of electron transport and ATP synthesis?
Electron transport occurs without ATP production, releasing energy as heat.
True or False: Malignant hyperthermia is caused by a leak in the mitochondrial membrane.
True.
What triggers the opening of thermogenin in brown fat cells?
Nor-epinephrine in response to cold.
What is the evolutionary significance of oxygen-involving mechanisms in respiration?
Allowed more potential energy to be released and conserved from food molecules, expanding the range of usable substrates.
What does the term ‘chemiosmosis’ refer to?
The movement of protons across a membrane, generating ATP.
Which complex in the electron transport chain is involved in the oxidation of FADH2?
Complex II: Succinate-Q reductase.
What is the function of ubiquinone in the electron transport chain?
Acts as an electron carrier, transferring electrons from Complexes I and II to Complex III.
Fill in the blank: The reduced co-reactants NADH and FADH2 eventually combine with _______ to form water.
oxygen.
What is the main product of the citric acid cycle per turn?
- 3 NADH
- 1 FADH2
- 1 GTP
What is the primary energy currency of cells produced during oxidative phosphorylation?
ATP.
What is the outcome of electron transport if the inner mitochondrial membrane becomes permeable to protons?
Electron transport continues, but no ATP is produced.
What are brown fat cells?
Specialized cells that generate heat through non-shivering thermogenesis
Brown fat cells are crucial in thermoregulation and energy expenditure.
What is intentional uncoupling?
A process where oxidative phosphorylation is uncoupled to generate heat instead of ATP
It can occur in both mammals and plants.
Which plant can attract insects through heat generation?
Arum lily
The Arum lily can heat up to 42°C even when the air temperature is 0°C.
What is the purpose of skunk cabbage melting snow?
To emerge from the ground and attract pollinators
Skunk cabbage can heat to 15°C in an environment where the air temperature is -15°C.
What does the citric acid cycle (CAC) produce?
Energy-containing NADH and FADH2
These molecules are critical for the electron transport chain.
How many protein complexes are involved in the electron transport chain?
Four
These complexes facilitate the movement of protons across the mitochondrial inner membrane.
What does the proton gradient act as in the electron transport chain?
A store of potential energy
This energy drives the production of ATP.
What is ATPase?
An enzyme that synthesizes ATP from ADP and inorganic phosphate
It utilizes the proton gradient generated by the electron transport chain.
What is the binding-change mechanism?
A model explaining how ATP is synthesized during oxidative phosphorylation
It describes changes in the ATPase enzyme structure that drive ATP production.
What happens when you uncouple oxidative phosphorylation?
Heat is produced instead of ATP
This can occur either intentionally or in disease states.
What is malignant hypothermia?
A genetic disorder that causes a severe reaction to certain anesthetics
It leads to increased calcium release from the sarcoplasmic reticulum and excessive heat production.
Fill in the blank: The stoichiometry of the complete breakdown of glucose is _____ .
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy
This equation summarizes the overall process of cellular respiration.
