To Protect Against Spam, Many ISPs and Most Web-Based Email

question 52

Short Answer

To protect against spam, many ISPs and most web-based email services provide _________________________ services.

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Definitions:

Electron Transport Chain

A series of complexes that transfer electrons from electron donors to electron acceptors via redox (reduction and oxidation) reactions, and the transfer of electrons is coupled with the transfer of protons (H+ ions) across a membrane, which generates ATP.

Proton Pumping

The active transport of hydrogen ions (protons) across a membrane, often creating a gradient used for energy production in cells.

Intermembrane Space

The region between the inner and outer membranes of mitochondria or chloroplasts, involved in energy production.

Fermentation

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen, utilized in food production and biofuel generation.