Final answer:
The parotid salivary glands produce about 20-25% of the saliva and are important for digestion and oral health.
Step-by-step explanation:
The parotid salivary glands are the largest of the three major pairs of salivary glands. These glands are situated on either side of the mouth, anterior and inferior to the ears, and they produce saliva that enters the mouth through the parotid duct, near the second upper molar tooth. The parotid glands are responsible for producing about 20-25% of the total saliva in the oral cavity, which is crucial for initiating digestion, lubricating food, and maintaining oral health.