Urine formation occurs in

Options

A. Liver
B. Kidneys
C. Spleen
D. Heart

Answer

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

1. **Understanding Urine Formation**: Urine formation is a crucial biological process that occurs in the body to eliminate waste products. It involves several key processes that take place in specific organs.

2. **Identifying the Organ**: The primary organ responsible for urine formation is the kidney. Each human has two kidneys, which are bean-shaped and reddish-brown in color.

3. **Processes Involved in Urine Formation**: The formation of urine occurs through three main processes:
- **Filtration**: This is the first step where blood is filtered in the kidneys to remove waste products.
- **Reabsorption**: In this second step, essential substances such as water, glucose, and ions are reabsorbed back into the bloodstream.
- **Secretion**: This final step involves the secretion of additional waste products into the urine.

4. **Nephrons**: The functional unit of the kidney is called the nephron. Each kidney contains approximately 1 million nephrons (2 million in total for both kidneys), which are responsible for the processes of filtration, reabsorption, and secretion.

5. **Urine Pathway**: Once urine is formed in the kidneys, it travels through the ureters to the urinary bladder, where it is stored until it is excreted through the urethra.

6. **Conclusion**: Based on the above information, we conclude that urine formation occurs in the kidneys.

**Final Answer**: Urine formation occurs in the kidneys.

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