Question

which step of cellular respiration is shown in the image? (1 point)
krebs cycle
electron transport chain
lactic acid fermentation
glycolysis

Explanation:

1. Analyze each option:

• Krebs cycle: Occurs in the matrix, involves acetyl - CoA oxidation, no electron transport chain components (like NADH reductase, cytochrome complexes, ATP synthase) shown here.
• Electron transport chain: The image shows components like NADH reductase, ubiquinone, cytochrome c, cytochrome oxidase, ATP synthase, and the flow of electrons (from NADH to O₂) and H⁺ transport, which are characteristic of the electron transport chain.
• Lactic acid fermentation: Anaerobic process, produces lactic acid, no components of electron transport chain or O₂ utilization as in the image.
• Glycolysis: Occurs in the cytoplasm, breaks down glucose, no electron transport chain components shown.

Answer:

B. electron transport chain