Which of the following is not a function of vertebrate liver

Options

A. Uptake and excretion of bilirubin
B. Bile production
C. Release of glycogen into blood
D. Urea synthesis

Answer

To determine which of the following is not a function of the vertebrate liver, let's analyze each option step by step.

### Step 1: Understand the Functions of the Liver
The liver has several important functions, including:
- Uptake and excretion of bilirubin
- Bile production
- Glycogen storage and conversion to glucose
- Urea synthesis

### Step 2: Analyze Each Option
1. **Uptake and Excretion of Bilirubin**:
- Bilirubin is a breakdown product of hemoglobin. The liver cells (hepatocytes) take up bilirubin, process it, and excrete it. This is indeed a function of the liver.

2. **Bile Production**:
- The liver produces bile, which contains bile salts and pigments. Bile is essential for the digestion and emulsification of fats. This is a primary function of the liver.

3. **Release of Glycogen in Blood**:
- Glycogen is stored in the liver and serves as a reserve energy source. However, the liver does not release glycogen directly into the blood; instead, it converts glycogen into glucose (a process known as glycogenolysis) and then releases glucose into the blood. Therefore, the statement "release of glycogen in blood" is misleading and not a direct function of the liver.

4. **Urea Synthesis**:
- The liver synthesizes urea from ammonia, which is a product of amino acid metabolism. This process is known as the urea cycle and is a crucial function of the liver.

### Step 3: Conclusion
Based on the analysis, the option that is not a function of the vertebrate liver is:
- **Release of Glycogen in Blood** (Option C)

### Final Answer
**Option C: Release of Glycogen in Blood is not a function of the vertebrate liver.**

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