Fossa ovalis is present on septum separating

Options

A. 1)Atria
B. 2)Ventricles
C. 3)Sinus venosus
D. 4)Aortae

Answer

To answer the question regarding the location of the fossa ovalis, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Fossa Ovalis**:
- The fossa ovalis is an oval depression located on the septal wall of the heart.
- It is a remnant of a structure that was present during fetal development, known as the foramen ovale.

2. **Identifying the Septum**:
- The septum in the heart refers to the wall that separates the left and right sides of the heart.
- There are two main septa: the interatrial septum (between the atria) and the interventricular septum (between the ventricles).

3. **Locating the Fossa Ovalis**:
- The fossa ovalis is specifically found on the interatrial septum, which separates the left atrium from the right atrium.
- It is located in the lower part of the septum, to the left of the inferior vena cava.

4. **Determining What It Separates**:
- Since the fossa ovalis is located on the interatrial septum, it separates the left atrium from the right atrium.

5. **Evaluating the Options**:
- The question provides four options:
1. Atria
2. Ventricles
3. Sinus venosus
4. Aorta
- Based on our understanding, the fossa ovalis separates the left and right atria.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the fossa ovalis is present on the septum separating the atria.

### Final Answer:
The fossa ovalis is present on the septum separating the left and right atria.

---