Which of the following is concerned with the formation of urea in rabbit ?

Options

A. blood
B. kidney
C. spleen
D. liver

Answer

To answer the question "Which of the following is concerned with the formation of urea in rabbit?", we can follow these steps:

### Step 1: Understand Urea Formation
Urea is formed in the liver through a process called the urea cycle. This cycle converts ammonia, which is toxic, into urea, which is less harmful and can be excreted from the body.

### Step 2: Identify the Organ Involved
The primary organ responsible for the formation of urea in rabbits (and other mammals) is the liver. The liver processes nitrogenous waste and converts it into urea.

### Step 3: Consider the Transport Mechanism
Once urea is formed in the liver, it is transported to the kidneys through the bloodstream. The kidneys then filter the blood and excrete urea along with other waste products in urine.

### Step 4: Conclude the Answer
The correct answer to the question is the liver, as it is the organ directly involved in the formation of urea in rabbits.

### Final Answer
The organ concerned with the formation of urea in rabbits is the **liver**.

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