Which tissue is NOT listed as containing nonsulfated sialomucins?

• A. Goblet cells
• B. Salivary glands
• C. Pancreas
• D. Liver

Answer: (D)

Nonsulfated sialomucins are a type of acidic mucin that contains sialic acid but not sulfate groups. They’re typical in tissues with mucous-secreting cells, helping to lubricate and protect surfaces. Goblet cells lining mucosal surfaces produce mucins that include nonsulfated sialomucins, giving the mucus its viscous, protective quality. Salivary glands also secrete mucins rich in nonsulfated sialomucins, contributing to the thickness and lubricating properties of saliva. The pancreas has ductal and mucous components that produce mucins as well, including nonsulfated sialomucins, though its main function is enzyme secretion rather than mucus production.

The liver, on the other hand, doesn’t rely on goblet cells or mucous-secreting ducts for its secretions; it primarily makes bile and plasma proteins rather than mucins. Because it lacks these mucin-secreting tissues, it’s not listed as containing nonsulfated sialomucins.