Final answer:
The laryngeal structures vary between children and adults in terms of size and development, with adults having a more developed and lower larynx which allows for a wider range of phonation due to the growth and differentiation of the laryngeal cartilages and vocal cords.
Step-by-step explanation:
The laryngeal structures in children and adults differ primarily in size and developmental stage. In children, the larynx is located higher in the neck, and the structures, including the thyroid cartilage, epiglottis, and cricoid cartilage, are less developed and smaller in size. As a child grows, these cartilaginous structures enlarge, with the most significant changes occurring during puberty, especially in males, where the growth of the larynx causes a deepening of the voice due to larger vocal cords and a more prominent Adam's apple. The epiglottis in both children and adults serves the crucial function of covering the trachea during swallowing, preventing food from entering the airways.
Additionally, in adults, the larynx lowers in the neck which allows for a larger range and differentiation of sounds, aiding in complex speech. This evolutionary change in the vocal tract development enabled humans to produce a wide array of sounds necessary for spoken language. The resulting larger larynx and differently shaped resonant cavities also contribute to the difference in pitch and tone between individuals.
In summary, while all the key cartilages such as the thyroid, cricoid, epiglottis, arytenoids, corniculates, and cuneiforms are present in both children and adults, they are more prominent and developed in adults. The functionality, however, remains constant with the larynx playing a pivotal role in protecting the airway during swallowing and facilitating phonation.