Chapter 5, Problem 1RQ

Which of the following are granulocytes?

1. Neutrophils

2. Monocytes

3. Eosinophils

4. Lymphocytes

5. Basophils

A. 2 only

B. 5 only

C. 2 and 4 only

D. 1,3, and 5 only

Summary Introduction

Introduction:

The white blood cells (WBCs) are one of the components of blood. White blood cells, along with red blood corpuscles, platelets, and proteins, form the blood. When the white blood cells, red blood corpuscles (RBCs), and the clotting factors are removed, the remaining fluid is known as the serum.

Answer to Problem 1RQ

Correct answer:

Neutrophils, basophils, and eosinophils are the granulocytes.

Explanation of Solution

Justification for the correct answer:

Option (D) states that neutrophils (1), eosinophils (3), and basophils (5) are the only granulocytes. Granulocytes are white blood cells in which the cytoplasm contains granules. Granulocytes are further distinguished on the basis of the shape of the nucleus. Granulocytic WBCs are of three types, namely neutrophils, basophils, and eosinophils. Hence, option (D) is correct.

Justification for the incorrect answers:

Option (A) states that monocytes (2) are the only granulocytes. Monocytes are non-granulated cells. When present in tissues, they have the capability of differentiating into macrophages. The process of adaptive immunity is influenced by the presence of monocytes. So, it is an incorrect option.

Option (B) states that basophils (5) are the only granulocytes. The basophils are not the only granulocytes present in the bloodstream. Neutrophils and eosinophils are also granulocytes. They are categorized on the basis of the presence of granules in them. So, it is an incorrect option.

Option (C) states that monocytes (2) and lymphocytes (4) are the only granulocytes. Lymphocytes and monocytes are agranulocytes, that is, they do not possess cytoplasmic granules. Together, they make up approximately 33% of the hematologic blood values. So, it is an incorrect option.

Hence, options (A), (B), and (C) are incorrect.

Conclusion

Thus, it can be concluded that granulocytes and agranulocytes are categorized on the basis of the presence of cytoplasmic granules. Neutrophils, eosinophils, and basophils are granulocytes. Monocytes and lymphocytes are agranulocytes.