How Does the Reductive (Reverse) TCA Cycle Participate in Carbon

question 56

Multiple Choice

How does the reductive (reverse) TCA cycle participate in carbon fixation?

• A) Some of the TCA reactions occur in reverse, assimilating small amounts of CO₂.
• B) CO₂ assimilation replenishes TCA intermediates for anabolic pathways.
• C) Reverse TCA regenerates acetyl-CoA, which may enter gluconeogenesis via pyruvate.
• D) All of the above.
• E) None of the above.

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Definitions:

Payback

A method of investment appraisal that calculates the time needed for an investment to generate cash flows sufficient to recover the initial outlay.

Four Year Payback

A capital budgeting method that calculates the time required to recoup the initial investment in a project, specifically over a period of four years.

Payback Period

The payback period is the length of time required to recover the cost of an investment, calculated by dividing the initial investment by the annual cash inflow.