The non-leukocyte tissue cells known as activate enzymes which produce leukotrienes and prostaglandins in response to allergen binding. The non-leukocyte tissue cells known as activate enzymes which produce leukotrienes and prostaglandins in response to allergen binding. A. mast cells B. basophils C. monocytes D. lymphocytes E. neutrophils

Mast cells. (Ans. A)

Explanation:

Mast cells are called the immune system of vertebrate species, they help to regulate some allergic responses, innate & adaptive immunity, and inflammation such as hypersensitivity. These cells circulate the amounts of their granules into the surrounding tissues, while stimulation by an allergen found and the process called degranulation.

Mast cells help to assist and awaken the immune system to local infection. Once these cells are activated, they generate inflammatory responses by secreting chemical mediators which are stored in preformed granules, and after activation occurs synthesizing leukotrienes and cytokines.

the dark variety, as they are not visible on the dark tree barks

explanation:

sorry, but you do not have posted the diagram.