Introduction:
Mucus is a viscous, slimy substance produced by certain glands and cells in the body. It plays a vital role in protecting and lubricating the surfaces of various organs. Several glands and cells contribute to mucus production in the body.

Associated Glands:
1. Submandibular gland: It is one of the three major salivary glands, located beneath the lower jaw. Submandibular gland secretes a mixture of saliva and mucus that keeps the mouth moist and lubricated.

2. Sublingual gland: It is another major salivary gland located under the tongue. Sublingual gland produces a thin, watery saliva that contains mucus.

3. Goblet cells: These are specialized epithelial cells found in various organs, such as the respiratory and digestive tracts. Goblet cells secrete mucus that protects and lubricates the surfaces of these organs.

Not Associated Gland:
4. Parotid gland: This is the largest of the three major salivary glands, located in front of the ears. Parotid gland secretes a watery saliva that does not contain mucus.

Conclusion:
In summary, submandibular gland, sublingual gland, and goblet cells are associated with mucus production, while the parotid gland is not. These glands and cells play an essential role in maintaining the health and function of various organs in the body.