Rima glottidis is the opening in between

Options

A. external nares
B. internal nares
C. conchae
D. vocal folds

Answer

**Step-by-Step Solution:**

1. **Understanding Rima Glottidis**: The rima glottidis is defined as an elongated opening or space within the larynx. It is crucial to recognize that this structure is not just any opening, but specifically relates to the vocal apparatus.

2. **Location of Rima Glottidis**: The rima glottidis is situated between the vocal folds (also known as vocal cords) at the front and the arytenoid cartilages at the back. This anatomical positioning is essential for its function in sound production.

3. **Anatomical Significance**: It is important to note that the rima glottidis is the narrowest part of the laryngeal cavity. This narrowness plays a significant role in the modulation of sound during phonation.

4. **Size Variation**: The length of the rima glottidis varies between genders. In males, it is approximately 23 millimeters, while in females, it ranges from 17 to 18 millimeters. This variation can influence voice pitch and quality.

5. **Subdivisions of Rima Glottidis**: The rima glottidis can be divided into two parts:
- **Intercartilaginous Part**: This part is located between the arytenoid cartilages.
- **Intramembranous Part (or Glottis Vocalis)**: This part lies between the vocal folds.

6. **Conclusion**: Based on the anatomical description and function, the correct answer to the question "Rima glottidis is the opening in between" is the vocal folds (option 4).

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