In humans, end product of purine metabolism –
**Core Concept**
In humans, purine metabolism involves the breakdown and recycling of purine nucleotides, ultimately producing an end product that is excreted in the urine. This process is crucial for maintaining proper levels of nucleic acids in the body.
**Why the Correct Answer is Right**
The end product of purine metabolism is uric acid, which is formed through the sequential action of several enzymes, including xanthine oxidase and urate oxidase. Uric acid is then excreted in the urine, where its concentration is influenced by factors such as diet, kidney function, and genetic predisposition. In individuals with normal purine metabolism, uric acid is the final product, whereas in some cases, such as gout, uric acid levels can become elevated.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not accurately represent the end product of purine metabolism. While AMP (adenosine monophosphate) is a purine nucleotide, it is not the end product of purine catabolism.
* **Option B:** This option is incorrect because it is not a known end product of purine metabolism. Although some purine analogs may be broken down to form other compounds, uric acid is the primary end product in humans.
* **Option C:** This option is incorrect because it is not a direct product of purine catabolism. While xanthine is an intermediate in the breakdown of purines, it is not the final product.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that elevated uric acid levels can lead to conditions such as gout, which is characterized by acute inflammatory arthritis and deposition of urate crystals in the joints.
**Correct Answer:** C. Uric acid.