Renal arteries ar formed by

Options

A. Ventral aorta
B. Dorsal aorta
C. Inferior venacava
D. Aortic arch

Answer

**Step-by-Step Solution:**

1. **Understanding the Formation of Renal Arteries:**
- Renal arteries are blood vessels that supply oxygenated blood to the kidneys. To understand how they are formed, we need to look at the major arteries in the body.

2. **Identifying the Source of Renal Arteries:**
- The primary source of renal arteries is the dorsal aorta. The dorsal aorta is a major artery that carries oxygenated blood from the heart to various parts of the body, including the kidneys.

3. **Role of the Dorsal Aorta:**
- The dorsal aorta emerges from the heart and travels down the body. As it approaches the kidneys, it branches off into the renal arteries, which specifically supply blood to the kidneys.

4. **Elimination of Incorrect Options:**
- The other options provided (ventral aorta, inferior vena cava, and aortic arch) do not contribute to the formation of renal arteries:
- **Ventral Aorta:** This is primarily found in embryos and carries blood from the heart, but it does not form renal arteries.
- **Inferior Vena Cava:** This vessel carries deoxygenated blood back to the heart from the lower body, not supplying blood to the kidneys.
- **Aortic Arch:** While it is a major artery, it does not directly form the renal arteries; it gives rise to other branches.

5. **Conclusion:**
- Therefore, the correct answer to the question "Renal arteries are formed by" is the **dorsal aorta**.