Entrance Exams
Govt. Exams
Pompe disease results from deficiency of acid α-glucosidase (lysosomal α-1,4-glucosidase), leading to accumulation of glycogen in lysosomes, especially in muscles and heart.
Under anaerobic conditions, pyruvate is reduced to lactate by lactate dehydrogenase (LDH) to regenerate NAD+ for continued glycolysis.
During exercise, epinephrine increases and ATP/AMP ratio decreases, both of which activate phosphorylase kinase and promote glycogenolysis.
Acetyl-CoA condenses with oxaloacetate to form citrate, which enters the citric acid cycle. Citrate synthase catalyzes this reaction.
Maltose is a reducing sugar because it has a free anomeric carbon. Sucrose and trehalose are non-reducing sugars as both anomeric carbons are involved in glycosidic bonds.
Anaerobic glycolysis produces 4 ATP molecules but consumes 2 ATP, resulting in a net gain of 2 ATP per glucose molecule.
Phosphofructokinase-1 (PFK-1) catalyzes the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate and is subject to allosteric inhibition by ATP and citrate.
Phosphoglucose isomerase catalyzes the isomerization of glucose-6-phosphate to fructose-6-phosphate in the second step of glycolysis.
Ribose is a 5-carbon (pentose) sugar, while glucose, galactose, and fructose are hexoses (6-carbon sugars).
Glycogen's highly branched structure with α-1,6-branch points every 8-12 glucose residues increases its solubility, provides multiple substrate sites for glycogen phosphorylase simultaneously, and enables rapid glucose mobilization during energy demands. This is metabolically superior to linear polymers.