Question

Hereditary fructose intolerance is an autosomal recessive genetic disorder characterized by the lack of the enzyme aldolase B. Symptoms include convulsions, excessive sleepiness, irritability, vomiting, and hypoglycemia. What intermediate accumulates in these individuals, and how may this be associated with the observed symptoms?

a) Fructose-1-phosphate accumulates; it inhibits gluconeogenesis
b) Glucose-6-phosphate accumulates; it impairs glycogen synthesis
c) Fructose-6-phosphate accumulates; it enhances glycolysis
d) Glyceraldehyde-3-phosphate accumulates; it activates lipogenesis

Answer 1

Hereditary fructose intolerance is characterized by the accumulation of fructose-1-phosphate due to the lack of the enzyme aldolase B. This accumulation is associated with symptoms such as convulsions, excessive sleepiness, irritability, vomiting, and hypoglycemia. Fructose-1-phosphate inhibits gluconeogenesis, leading to a decrease in blood glucose levels and the observed symptoms.

Step-by-step explanation:

The intermediate that accumulates in individuals with hereditary fructose intolerance is fructose-1-phosphate. This accumulation is due to the lack of the enzyme aldolase B, which is necessary for the breakdown of fructose-1-phosphate. The observed symptoms, such as convulsions, excessive sleepiness, irritability, vomiting, and hypoglycemia, can be associated with the accumulation of fructose-1-phosphate. Fructose-1-phosphate inhibits gluconeogenesis, the process of producing glucose from non-carbohydrate sources, which can lead to a decrease in blood glucose levels and the symptoms experienced by these individuals.