Electron Transport Chain

Flashcards covering key concepts from the lecture on the electron transport chain, including its functions, complexes, and biochemical processes.

What is the primary function of the electron transport chain?

To create a proton gradient using high energy electrons.

Where does the citric acid cycle take place?

In the mitochondrial matrix.

Which carriers transport the high energy electrons generated in the citric acid cycle?

NADH and FADH2.

What happens to electrons at the end of the electron transport chain?

They are transferred to oxygen and reduced to form water.

What is the energy used for during the electron transport chain process?

To pump protons from the matrix into the inter membrane space.

Which complexes in the electron transport chain are proton pumps?

Complexes I, III, and IV.

What type of reactions occurs in the electron transport chain?

Redox (oxidation-reduction) reactions.

Why is complex II not considered a proton pump?

It doesn't pump protons across the membrane.

How do electrons from NADH contribute to the electron transport chain?

They are oxidized and transferred through several complexes, contributing to the proton gradient.

What is the role of cytochrome c in the electron transport chain?

It carries electrons between Complex III and Complex IV.

How is proton movement facilitated in Complex I of the electron transport chain?

Through conformational changes triggered by the charge of reduced ubiquinone.

What is the outcome of the reaction catalyzed by Complex IV?

Reduction of oxygen to form water, using protons from the matrix.

What is indicated by a positive cell potential in electrochemical reactions?

The reaction is spontaneous (galvanic).

What does the respiratory chain refer to?

Another name for the electron transport chain.

Why are electrons carried by NADH more energy-rich than those carried by FADH2?

Due to a higher reduction potential, NADH releases more energy upon oxidation.

What happens to protons in the inner mitochondrial space during oxidative phosphorylation?

They create a proton gradient that is used to synthesize ATP.

Which enzyme complex has 45 polypeptide chains and is well conserved across species?

Complex I.

How is ATP produced at the end of the electron transport chain?

Through ATP synthase, as protons flow back into the matrix.

What is the Gibbs free energy change equation for electrical systems?

ΔG = -nFΔE.