In which one of the following options the two examples are correctly matched with their particular type of immunity ?

Options

A. `{:("Examples" , "Type of immunity"),("Polymorphonuclear leukocytes and monocytes ","Cellular barriers"):}`
B. `{:("Examples" , "Type of immunity"),("Anti-tetanus and anti-snake bite injections ","Active immunity"):}`
C. `{:("Examples" , "Type of immunity"),("Saliva in mouth and tears in eyes ","Physical barriers"):}`
D. `{:("Examples" , "Type of immunity"),("Mucus coating of epithelium ","Chemical barriers"):}`

Answer

A

Explanation

Phagocytosis is an important feature of cellular innate immunity, performed by cells called phagocytes that engulf or eat pathogens or foreign particles. Common examples of these phagocytes are monocytes, macrophages, neutrophil granulocytes (often referred to as polymorphonuclear leukocytes or PMN or PML, because of the varying shapes of nucleus), tissue dendritic cells, mast cells etc. Anti-tetanus and anti snake bite injections are examples of passive immunity.