Glycolysis and Glucose Transport Quiz

The phosphorylation of glucose to glucose-6-phosphate (G6P) is the key regulatory step in glycolysis. This reaction is catalyzed by hexokinase, which is tightly regulated to ensure that glucose is only used when needed.

The enzyme aldolase catalyzes the cleavage of fructose-1,6-bisphosphate (F1,6BP) into two three-carbon molecules: glyceraldehyde-3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP).

GLUT4 is a glucose transporter protein found in muscle and adipose tissue. Its expression and activity are regulated by insulin, facilitating glucose uptake into cells.

Phosphofructokinase-1 (PFK-1) catalyzes the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate (F1,6BP), a crucial irreversible step in glycolysis.

AMP, a molecule that indicates low energy levels in the cell, allosterically stimulates the activity of PFK-1, increasing glycolysis and ATP production.

Hexokinase is the enzyme responsible for the phosphorylation of glucose to glucose-6-phosphate (G6P), the first committed step in glycolysis.

PFK-1 is a key regulatory enzyme in glycolysis. It catalyzes the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate (F1,6BP), a committed and irreversible step in the pathway.

The net gain of ATP produced per glucose molecule during glycolysis is 2 ATP. While 4 ATP are generated, 2 are used in the initial steps, resulting in a net gain of 2.

Under anaerobic conditions, pyruvate is converted to lactate. This process is also called lactic acid fermentation and it regenerates NAD+, which is essential for glycolysis to continue.

The Warburg effect is a shift in the metabolism of cancer cells towards glycolysis, even in the presence of oxygen. This phenomenon allows rapid cell proliferation despite limited oxygen availability.

2,3-bisphosphoglycerate (2,3-BPG) is a byproduct of glycolysis in red blood cells (RBCs). It binds to hemoglobin, decreasing its affinity for oxygen and promoting oxygen release in tissues.

Glucose-6-phosphate can be utilized for various metabolic pathways including glycolysis, glycogen synthesis, the pentose phosphate pathway, and others, making it a metabolic branch point.