The first step in liver’s metabolism of fructose is ?
**Core Concept**
The liver's metabolism of fructose involves a series of enzymatic reactions that convert it into intermediates that can be used for energy production or stored as glycogen. The first step in this process is catalyzed by a specific enzyme that facilitates the conversion of fructose into a more reactive intermediate.
**Why the Correct Answer is Right**
The correct answer involves the enzyme aldolase B, which catalyzes the conversion of fructose-1-phosphate into glyceraldehyde and dihydroxyacetone phosphate. This step is crucial in the metabolism of fructose, as it allows the liver to generate intermediates that can be used for energy production or stored as glycogen. The enzyme aldolase B is specifically involved in this reaction, and its activity is essential for the proper metabolism of fructose in the liver.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not accurately describe the first step in the liver's metabolism of fructose.
* **Option B:** This option is incorrect because it involves a different enzyme and a different step in the metabolism of fructose.
* **Option D:** This option is incorrect because it does not accurately describe the first step in the liver's metabolism of fructose, and the enzyme involved in this reaction is not specified.
**Clinical Pearl / High-Yield Fact**
Aldolase B deficiency is a rare genetic disorder that affects the metabolism of fructose, leading to the accumulation of fructose-1-phosphate in the liver and causing symptoms such as hypoglycemia, hepatomegaly, and vomiting. This condition highlights the importance of the first step in the liver's metabolism of fructose and the role of aldolase B in maintaining normal glucose and lipid homeostasis.
**Correct Answer: C. Aldolase B catalyzes the conversion of fructose-1-phosphate into glyceraldehyde and dihydroxyacetone phosphate.**