1. Where does pyruvate formation during glycolysis take place in a eukaryotic cell?
A.
Cytoplasm
B.
Nucleus
C.
Mitochondrial matrix
D.
Chloroplast stroma
Correct Answer:
Cytoplasm
Explanation:
Glycolysis, including the formation of pyruvate, occurs in the cytoplasm of the cell.
2. How many molecules of pyruvate are formed from one molecule of glucose during glycolysis?
A.
One
B.
Two
C.
Three
D.
Four
Correct Answer:
Two
Explanation:
A six-carbon glucose molecule is split into two three-carbon molecules, and each forms one pyruvate.
3. What is the carbon number of one pyruvate molecule formed in glycolysis?
A.
Two
B.
Three
C.
Four
D.
Six
Correct Answer:
Three
Explanation:
Pyruvate is a three-carbon product formed when the six-carbon glucose molecule is split during glycolysis.
4. Which molecule is directly converted into pyruvate in the final step of glycolysis?
A.
Glucose
B.
Fructose-6-phosphate
C.
Phosphoenolpyruvate
D.
Lactic acid
Correct Answer:
Phosphoenolpyruvate
Explanation:
Phosphoenolpyruvate, or PEP, is converted into pyruvate in the final step of glycolysis.
5. Which enzyme catalyzes the final step of pyruvate formation in glycolysis?
A.
Hexokinase
B.
Phosphofructokinase
C.
Pyruvate kinase
D.
Lactate dehydrogenase
Correct Answer:
Pyruvate kinase
Explanation:
Pyruvate kinase catalyzes the conversion of phosphoenolpyruvate into pyruvate.
6. How many net ATP molecules are produced when one glucose molecule is converted into pyruvate during glycolysis?
A.
One
B.
Two
C.
Four
D.
Six
Correct Answer:
Two
Explanation:
Glycolysis produces four ATP molecules but uses two ATP molecules, giving a net gain of two ATP per glucose.
7. What type of ATP production occurs during the conversion of phosphoenolpyruvate to pyruvate?
A.
Oxidative phosphorylation
B.
Photophosphorylation
C.
Substrate-level phosphorylation
D.
Chemiosmosis only
Correct Answer:
Substrate-level phosphorylation
Explanation:
In this step, a phosphate group is transferred directly from phosphoenolpyruvate to ADP to form ATP.
8. Besides pyruvate, which reduced electron carrier is produced during glycolysis?
A.
FADH2
B.
NADH
C.
ATP synthase
D.
Acetyl-CoA
Correct Answer:
NADH
Explanation:
During glycolysis, NAD+ is reduced to NADH while glucose is converted into pyruvate.
9. What is the main end product of glycolysis before any further metabolic processing?
A.
Pyruvate
B.
Acetyl-CoA
C.
Carbon dioxide
D.
Lactose
Correct Answer:
Pyruvate
Explanation:
Glycolysis ends with the formation of pyruvate from glucose.
10. What happens to the six-carbon glucose molecule during pyruvate formation in glycolysis?
A.
It remains unchanged as a six-carbon molecule
B.
It is split into two three-carbon molecules
C.
It combines with oxygen to form one six-carbon product
D.
It is converted directly into two two-carbon molecules
Correct Answer:
It is split into two three-carbon molecules
Explanation:
Glycolysis divides glucose into two three-carbon pathways, each ending in the formation of one pyruvate molecule.
Short questions are currently unavailable for this page.