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

Cytochrome c plays a critical role in the electron transport chain, which is a vital component of cellular respiration. It is a small heme protein that resides in the inner mitochondrial membrane and functions as an electron carrier. Its primary significance lies in its ability to accept electrons from complex III (cytochrome bc1 complex) and transfer them to complex IV (cytochrome c oxidase). This transfer of electrons is essential for the continuation of the electron transport process.

As electrons are transported through the chain, they help pump protons (H+) from the mitochondrial matrix into the intermembrane space. This creates a proton gradient across the mitochondrial membrane, which is essential for the synthesis of ATP. The gradient drives ATP synthase, allowing for the conversion of ADP and inorganic phosphate into ATP during oxidative phosphorylation. Hence, cytochrome c directly contributes to the establishment of this proton gradient, which is fundamental for energy production in the cell.

In contrast, other options refer to processes not closely associated with the role of cytochrome c. The initial breakdown of glucose occurs during glycolysis, while the Krebs cycle involves a different set of enzymes and molecules altogether. Additionally, fatty acid synthesis is a distinct metabolic pathway unrelated to the function of cyto