how many carbons from one glucose molecule enter one round of krebs cycle?

Question

how many carbons from one glucose molecule enter one round of krebs cycle?

Answer 1

6 carbons in a Glucose molecule (Fructose, Mannose, Galactose as well).
2 molecules of pyruvate (has 3 carbons each) from one Glucose.
Each pyruvate loses one carbon via pyruvate dehydrogenase complex and the remaining 2 carbons enter kreb's cycle.

So.. the answer is 2 since only 2 carbons from pyruvate (in the form of an acetate) are contributed to oxaloacetate to form citrate.

Answer 2

Two carbons enter each round of the Krebs cycle.

-- Glycolysis ended with two 3-carbon molecules.
-- The transition phase removed one carbon dioxide from each of the 3-carbon molecules, leaving 2-carbon molecules.

Answer 3

two