There are a lot of organs which help a person speak with proper pronunciation and clarity. Some organs are helpful in differentiating the sounds through articulation.
Lungs
They act as the main source of energy for speech. It has small air pockets called alveoles in which oxygen is stored. When the air in the alveolus is pushed up, the displaced air comes up the windpipe (trachea) and reaches the larynx. The air passes through the larynx and reaches pharynx. By adjusting the various parts in the mouth different speech sounds are produced before the lung air goes out into the atmosphere either through the mouth (oral passage) or the nose (nasal passage).
Larynx
It is the protruding part of the throat commonly called Adam’s apple. It is also known as the soundbox of the body.
Vocal cords
They are two elastic strips placed across the larynx facing each other. They are fixed at one end (far end) and free at the other. In the case of normal breathing, the vocal cords are drawn apart leaving a gap between them through which the air passes freely from the lungs. This gap between the vocal cords is known as glottis. Sometimes while speaking, the vocal cords are brought into contact with each other gently. In this position, the air from the lungs pushes through these vocal cords setting them in vibration. Speech sounds that are produced with the vocal cords vibrating are known as voiced sounds, e.g. /z/. sometimes, speech sounds are produced with the vocal cords, not in contact with each other and hence not vibrating such speech sounds which are known as voiceless sounds. E.g. /s/
Glottal Stop /p/
It happens when the vocal cords are brought into contact with each other rather firmly and thus stopping the air from passing through them.
Lips
The two lips are flexible organs of speech. They can combine with each other to produce certain sounds, e.g. /p, b/. sometimes the lower lip can combine with upper front teeth to produce certain sounds, e.g. /f, v/
The Roof of the Mouth
It consists of the upper front teeth, alveolar ridge, palate or hard palate and soft palate.
Teeth
The upper front teeth are fixed part of speech. The upper front teeth can combine with the lower lip to produce some sounds like /f, v/. they can also combine with the tongue to produce certain sounds like /ð/ as in this, either, θ as in thing, myth.
Alveolar Ridge
It is a hard, bulging, bony part found immediately behind the upper front teeth. This can combine with the tongue to produce certain sounds like /l, t, n/
Palate
It is also known as a hard palate.it is the hard-concave part of the roof of the mouth. Sometimes it can combine with the tongue to produce certain sounds, e.g. /j/
Soft Palate
It is soft, loosely hanging, the fleshy part after the hard palate. This can be in 3 positions.
- In between the wall of the mouth and back of the tongue. This is the position of the soft palate in the case of normal breathing. This position is also known as a neutral position. It can be raised sufficiently to be in firm contact with the wall of the mouth. Then the nasal passage is completely blocked, and all the lung air passes out only through the oral passage (mouth).
- It can also be lowered sufficiently to be in firm contact with the back of the tongue. Thus, the oral passage is completely locked and all the air from the lung passes out only through the nasal passage (nose).
- Certain sounds are produced with soft palate and the tongue combining with each other. E.g. /k, g/. the tip of the soft palate is called vellum.
Tongue
It is the most flexible part; the prime organ of speech. The tongue is divided into 4 parts namely, the tip, the blade, the front, and the back. The tip of the tongue can move in the direction of the back part of the upper front teeth in the production of certain sounds. / ð, θ/
The Blade
It can combine with the alveolar ridge to produce certain sounds, /t, s, n/
The Front
The front of the tongue can combine with the hard palate to produce certain sounds, /I, i:, j/
The Back
The back of the tongue combines with the soft palate to produce certain sounds, /k/.