The levetor veli palatini muscle elevates the soft palate, the muscle uvulae bunches the soft palate, and the tensor veli palatini tenses and shortens the palate.
During swallowing, the soft palate and uvula move upward to prevent food from entering the nasal cavity, the uvula also helps to guide the food into the pharynx.
By contrast, lying on your side helps to clear the upper airway and prevents the uvula (the fleshy bit that hangs down in the back of your throat) and the tongue from obstructing the throat, leading to less snoring.
The different moving parts are known as articulators, and the main ones are the tongue, upper lip, lower lip, upper teeth, alveolar ridge, hard palate, soft palate, uvula, the pharyngeal wall, and the glottis.