Protons Can Have Different Fates in Bacterial ETS

question 33

Multiple Choice

Protons can have different fates in bacterial ETS. Which of the following processes does NOT affect the proton motive force (Δp) ?

• A) Protons are pumped across the membrane (H+) by oxidoreductase complexes.
• B) Protons are consumed from the cytoplasm by the quinone/quinol pool.
• C) Protons are released outside the membrane from the quinone/quinol pool.
• D) Protons are consumed by combining with terminal electron acceptors such as O₂.
• E) Protons combining with O₂, used as a terminal acceptor, compensate protons released by catabolic pathways.

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Definitions:

Variable Costing

An accounting method that only includes variable production costs—costs that change with production volume—in the cost of goods sold.

Fixed Costs

Expenses that do not change with the level of goods or services produced by a business within a certain range of activity.

Cost of Goods Manufactured

The total production cost of goods completed during a specific period, including materials, labor, and overhead.

Variable Costing

An accounting method that considers only variable costs as product costs and treats fixed costs as period costs.