Question

Mast cells secrete.

• A. Serotonin
• B. Heparin
• C. Histamine
• D. All the above

Answer 1

The correct option is D All the above

• Mast cells are found in mucous membranes and connective tissues and are important for wound healing and defense against pathogens via the inflammatory response.
• The mast cell granules are composed of serotonin, heparin, and histamine. They secrete serotonin, heparin, and histamine when they are activated in the presence of the toxic substance or a pathogen.
• Hence Mast cells secrete 'serotonin, heparin, and histamine'.
• So, the correct answer is 'All the above'.