RRB Nsg. Superintendent-21 July 2019 (Shift-2nd)
Applied Physiology
Easy

Which among the following do the phagocytic action?

Appeared in: RRB Nsg. Superintendent-21 July 2019 (Shift-2nd)

Explanation

  • Neutrophils are the most abundant type of granulocytes and are the primary phagocytic cells in the blood.
  • They are considered the first line of defense in the body's innate immune system, migrating quickly to sites of infection or injury.
  • Their main function is to engulf and destroy microorganisms, particularly bacteria, through a process called phagocytosis.
  • Dead neutrophils, along with bacteria and tissue debris, are a major component of pus.

Why Other Options Were Wrong

  • Option B: Eosinophils are only weakly phagocytic. Their primary role is to defend against larger parasites like helminths (worms) and to participate in allergic reactions.
  • Option C: The term 'Polymorphs' (or polymorphonuclear leukocytes) is a general category that includes neutrophils, eosinophils, and basophils. It is not a specific cell type.
  • Option D: Basophils are not phagocytic cells. Their primary function is to release potent chemical mediators, such as histamine and heparin, which are involved in inflammatory and allergic reactions.

Related Visual

A flowchart illustrating the process of phagocytosis, showing a neutrophil engulfing and digesting a bacterium.
  • Visual 1: Diagram - A flowchart illustrating the process of phagocytosis, showing a neutrophil engulfing and digesting a bacterium.
  • Visual 2: Micrograph - A stained blood smear image comparing the appearance of a neutrophil, eosinophil, and basophil, highlighting their distinct nuclear shapes and granular staining.
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Functions of White Blood Cells (Leukocytes) as background academic context rather than a clinical decision trigger.
  • Nurses frequently review the Complete Blood Count (CBC) with differential. A high neutrophil count (neutrophilia) is a critical indicator of an acute bacterial infection, guiding antibiotic therapy.
  • Conversely, a low neutrophil count (neutropenia), often seen in chemotherapy patients, drastically increases infection risk. This requires implementing neutropenic precautions to protect the patient.
  • What if? If a patient's lab results showed a normal neutrophil count but a significantly elevated eosinophil count (eosinophilia), the nurse's assessment should shift from suspecting a bacterial infection to considering an allergic reaction or a parasitic infection as the underlying cause.
How to Approach the Question
  • This is a factual recall question testing knowledge of hematology.
  • First, identify the key process in the question: 'phagocytic action'. This means the engulfing and destruction of foreign particles.
  • Next, review the function of each cell type listed in the options.
  • Evaluate Option A (Neutrophils): Recall that these are the primary phagocytes of the immune system.
  • Evaluate Option B (Eosinophils) and D (Basophils): Recall their main roles are in parasitic/allergic reactions and allergic responses, respectively, not primary phagocytosis.
  • Evaluate Option C (Polymorphs): Recognize this as a broader category that includes neutrophils. When a specific, correct option ('Neutrophils') and a general category that contains it ('Polymorphs') are both choices, the more specific option is the better answer.
Concept Tested & Keywords
  • Concept Tested: Functions of White Blood Cells (Leukocytes)
  • Stem keywords: phagocytic action, Neutrophils, Eosinophils, Polymorphs, Basophils
  • Lead-in keywords: Which among the following

Question ID

QESsR375vxb_s26JNISS0P

Practise the full RRB Nsg. Superintendent-21 July 2019 (Shift-2nd)

Attempt every question from this paper in a timed mock, then review the full solution for each one.