Metabolism, glycolysis through electron transport

What are oxidation-reduction reactions in biological systems?

Oxidation is the loss of electrons, and reduction is the gain of electrons. These reactions are key to energy transfer in cells, especially during cellular respiration.

What is the role of electron carriers in energy metabolism?

: Electron carriers like NAD⁺ and FAD transport electrons during cellular respiration, transferring them from glucose to the electron transport chain for ATP production.

What is the role of ATP in biological systems?

ATP provides energy for cellular processes by releasing energy when its phosphate bonds are broken (ATP → ADP + Pi).

What is glycolysis and where does it occur?

Glycolysis is a ten-step process that breaks glucose into 2 pyruvate molecules, generating 2 ATP and 2 NADH, occurring in the cytoplasm (prokaryotes).

What are the key substrates and products of glycolysis?

Substrates: glucose, ATP, NAD⁺. Products: pyruvate, ATP (net 2), NADH.

How does aerobic respiration differ from fermentation?

Aerobic respiration uses oxygen to fully oxidize glucose, producing ~30-32 ATP. Fermentation occurs without oxygen and yields only 2 ATP

How is pyruvate oxidation linked to the citric acid cycle?

pyruvate enters the mitochondrial matrix and is converted to acetyl-CoA, producing NADH and CO₂. Acetyl-CoA enters the citric acid cycle.

Where do the steps of pyruvate oxidation and the citric acid cycle occur?

Pyruvate oxidation and the citric acid cycle occur in the mitochondrial matrix.

What happens to carbon and electrons in the citric acid cycle?

Carbon from acetyl-CoA is released as CO₂. Electrons are transferred to NAD⁺ and FAD, forming NADH and FADH₂

What are the oxidation reactions in the citric acid cycle?

Oxidations include steps where NAD⁺ and FAD are reduced to NADH and FADH₂, and CO₂ is released

What is the structure and function of the electron transport chain (ETC)?

The ETC is a series of protein complexes in the inner mitochondrial membrane that transfer electrons and pump protons to create a proton gradient

How does the proton gradient drive ATP synthesis?

Protons flow back into the mitochondrial matrix through ATP synthase, powering the conversion of ADP and Pi into ATP (chemiosmosis).

How many ATP molecules are produced from aerobic respiration?

Up to 32 ATP: ~2 from glycolysis, ~2 from the citric acid cycle, and ~28 from oxidative phosphorylation.