Question

With the length of the vocal cords, voice quality
A) changes
B) remains same
C) may or may not change
D) remains same but loudness changes

Answer 1

Hint: In human beings, vocal cords are folds of tissues, located in the throat region, for the production of sounds through mouths. It is generally seen that the voice produced by males has low pitch whereas the voice produced by females has high pitch. The pitch of sound produced by a human being with the help of vocal cords is highly dependent on the length of the vocal cords.

Complete step by step answer:
Vocal cords in humans are also known as vocal folds, which are nothing but folds of tissues, seen in their throat region. These tissue folds help humans in the production of sounds through their mouths. When a human being starts talking, pressure is applied so that air is passed from the lungs through the vocal passage, in which vocal folds are present. These vocal cords of particular lengths start vibrating, to create the sensation of voice, produced by humans, through their mouths. The quality of voice produced by human beings is highly dependent on the length of vocal cords in their throat.
It is generally seen that males have low pitch voices whereas females have high pitch voices. The reason behind this magic of nature is nothing but the length of vocal cords present in their throats. In males, vocal cords have lengths ranging from $1.75cm$ to $2.5cm$ whereas in females, vocal cords have lengths ranging from $1.25cm$ to $1.75cm$. When length or size of vocal cords is more, more air from the lungs passes through the vocal cords, thus creating a low pitch sound. On the other hand, when the length of vocal cords is less, less air from the lungs passes through the vocal cords, thus creating a high pitch sound.
Hence, with the length of the vocal cords, the quality of voice changes.

So, the correct answer is “Option A”.

Additional Information: In children, lengths of vocal cords are very small that they produce high pitch sounds. Also, when boys grow into adults, their vocal folds increase in size, which can be perceived as a change-in-voice process in boys, during their teenage. Lengths of vocal cords in humans are not only dependent on sexuality but also on genetic factors.

Note: The vocal cords or vocal folds in human beings work by oscillating or vibrating, when air passes through the opening in between the folds. The fundamental frequency of voice produced by a human being is dependent on the length, size and tension of the vocal cords. Males produce voices of an average fundamental frequency of $125Hz$ whereas females produce voices of an average fundamental frequency of $210Hz$. At the same time, children produce voices of an average fundamental frequency over $300Hz$.