The yellow colour of urine is due to the presence of

Options

A. urea
B. uric acid
C. urochrome
D. bilirubin

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Urine Color**: The color of urine is an important characteristic that can indicate various health conditions. The typical yellow color of urine is a common observation.

2. **Identifying the Substance Responsible for Color**: The yellow color of urine is primarily due to the presence of a pigment. This pigment is known as urochrome.

3. **Formation of Urochrome**: Urochrome is derived from the breakdown of hemoglobin. When red blood cells are broken down, bilirubin is produced. In the intestines, a portion of bilirubin is converted into urobilinogen through bacterial action.

4. **Reabsorption and Excretion**: Some of the urobilinogen is reabsorbed back into the bloodstream, while the majority is excreted by the liver into the intestines. A small percentage (about 5%) of urobilinogen is filtered by the kidneys and excreted in urine.

5. **Oxidation of Urobilinogen**: When urine is exposed to air, urobilinogen undergoes oxidation to form urobilin, which is the actual compound that gives urine its yellow color.

6. **Conclusion**: Therefore, the yellow color of urine is due to the presence of urochrome, which is formed from the oxidation of urobilinogen.

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