Question

Which of the following cells is not phagocytic in nature?
A. Mast cells
B. RBC
C. Macrophages
D. Neutrophils

Answer 1

The cell engulfs a particle and secretes digestive enzymes to digest it. This process is called phagocytosis. This process is adopted by many unicellular organisms as their mode of nutrition. Our body defence system works on this principle.

Complete Answer:
White blood cells are the defensive cell in our body. They are present in the blood which helps the body against foreign infectious particles or disease causing microbes. WBCS are divided into two categories according to the presence and absence of granules-
(I) Granulocytes- These cells contain granular cytoplasm. They can even kill parasites. They are involved in phagocytosis. The granulocytes are Neutrophils, Eosinophils, Basophils.
(II) Agranulocytes do not have granules in the cytoplasm. They are present in the lymphatic system. They aid in fighting against disease by secreting antibodies. They do not kill parasites.

They are of two types-Lymphocytes, Monocytes.
(i) Macrophages- They are the cells of the immune system which are involved in engulfing and destroying the foreign particles.
(ii) Mast Cells- They are the defensive cells present in our body which acts on the pathogens by phagocytosis. They are produced by the bone marrow.
(iii) RBC- This is nucleated red blood cells present in the blood. Their main function is transport of gases.

Thus the correct answer is (B). RBC is not phagocytic in nature.

Note: The macrophages present in our body are meant for the first line of defence in our body. These cells recognise and engulf the antigens. They break down the foreign particles in smaller proteins which are further acted upon by T-lymphocytes.