Gluconeogenesis

This video tutorial explains gluconeogenesis, a metabolic pathway that synthesizes glucose from non-carbohydrate sources. It highlights the differences from glycolysis, focusing on the three irreversible steps that require different enzymes. The process starts with pyruvate and involves key enzymes like pyruvate carboxylase and phosphoenolpyruvate carboxykinase. The tutorial also covers the conversion of fructose 1,6-bisphosphate to glucose and discusses the regulation of gluconeogenesis through energy charge and allosteric enzyme inhibition.

What is the primary goal of gluconeogenesis?

• To convert glucose into pyruvate

• To convert pyruvate into glucose

• To produce ATP from glucose

• To break down fatty acids

Which enzyme is responsible for the conversion of pyruvate to oxaloacetate?

• Pyruvate kinase

• Pyruvate carboxylase

• Phosphofructokinase

• Hexokinase

What molecule is used by pyruvate carboxylase in the conversion of pyruvate to oxaloacetate?

• Carbon dioxide

• Bicarbonate

• NADH

• FADH2

Which enzyme catalyzes the conversion of oxaloacetate to phosphoenolpyruvate?

• Phosphoglycerate mutase

• PEP carboxykinase

• Pyruvate kinase

• Hexokinase

What is the role of GTP in the conversion of oxaloacetate to phosphoenolpyruvate?

• It is a byproduct of the reaction

• It acts as a substrate

• It inhibits the reaction

• It provides energy for the reaction

What is the function of fructose 1,6-bisphosphatase in gluconeogenesis?

• To add a phosphate group to fructose 6-phosphate

• To remove a phosphate group from fructose 1,6-bisphosphate

• To convert glucose to fructose

• To catalyze the formation of ATP

Which enzyme is responsible for converting fructose 6-phosphate to glucose 6-phosphate?

• Phosphoglucose isomerase

• Fructose 1,6-bisphosphatase

• Hexokinase

• Pyruvate kinase

What happens to the activity of glycolysis enzymes when energy charge is high?

• They remain unchanged

• They are inhibited

• They are activated

• They are degraded

Which of the following enzymes is NOT allosterically regulated in glycolysis?

• Phosphoglucose isomerase

• Hexokinase

• Pyruvate kinase

• Phosphofructokinase

What is the effect of low energy charge on gluconeogenesis?

• It has no effect

• It inhibits gluconeogenesis

• It promotes gluconeogenesis

• It converts glucose to glycogen