The Most Ancient CO₂ Fixation Pathway in Methanogens Is the

question 55

Multiple Choice

The most ancient CO₂ fixation pathway in methanogens is the

• A) reverse TCA cycle.
• B) 3-hydroxypropionate cycle.
• C) Calvin cycle.
• D) reductive acetyl-CoA pathway.
• E) Krebs cycle.

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Definitions:

Increasing Order

A sequence arrangement from the lowest to the highest value, often used in chemistry to describe trends in properties or reactivities.

Acid-base Extractions

A technique in organic chemistry used to separate compounds based on their differences in solubility in acidic or basic environments.

Benzoic Acid

An aromatic carboxylic acid with the formula C6H5COOH, used in the manufacture of various cosmetics and pharmaceuticals.

Trichloroacetic Acid

A powerful acetic acid derivative (CCl3COOH), used as a reagent in organic synthesis and as a cauterizing agent in medicine.