Glyceraldehyde-3-phosphate was radioactively labeled with carbon-14 [ 14 C] on i
ID: 179955 • Letter: G
Question
Glyceraldehyde-3-phosphate was radioactively labeled with carbon-14 [14C] on its number 3 carbon (C3). Food availability was removed from a mouse to put the mouse into a fasting state. The [14C]-glyceraldehyde-3-phosphate was then injected into the mouse's blood and the radioactive compound was taken up by the liver. After a short time, glucose was identified in the plasma with [14C]-label at its number 1 and 6 carbons. Where did the second [14C]-label in plasma glucose come from?
Answers:
Condensation reaction using a second molecule of [14C]-glyceraldehyde-3-phosphate.
From return of carbons to glycolysis from the pentose phosphate pathway.
Aldolase reaction forming fructose-1,6-bisphosphate from [14C]-glyceraldehyde-3-phosphate and [14C]-dihydroxyacetone phosphate.
Oxidation of [14C]-glyceraldehyde-3-phosphate to fructose-1,6-bisphosphate.
Isomerization of glucose-6-phosphate to fructose-6-phosphate by phosphoglucoisomerase.
Glyceraldehyde-3-phosphate was radioactively labeled with carbon-14 [14C] on its number 3 carbon (C3). Food availability was removed from a mouse to put the mouse into a fasting state. The [14C]-glyceraldehyde-3-phosphate was then injected into the mouse's blood and the radioactive compound was taken up by the liver. After a short time, glucose was identified in the plasma with [14C]-label at its number 1 and 6 carbons. Where did the second [14C]-label in plasma glucose come from?
Answers:
Condensation reaction using a second molecule of [14C]-glyceraldehyde-3-phosphate.
From return of carbons to glycolysis from the pentose phosphate pathway.
Aldolase reaction forming fructose-1,6-bisphosphate from [14C]-glyceraldehyde-3-phosphate and [14C]-dihydroxyacetone phosphate.
Oxidation of [14C]-glyceraldehyde-3-phosphate to fructose-1,6-bisphosphate.
Isomerization of glucose-6-phosphate to fructose-6-phosphate by phosphoglucoisomerase.
Explanation / Answer
From return of Pentose phosphate shunt to the Glycolysis, the carbons are derived,the radioactive C14 Glyceraldehyde 3 phosphate from HMP to glucose obtained in gluconeogenesis so the glucose C14 is observed in the blood circulation due to administration of radio active carbon.