What is the average lifespan of Red blood cells?

Appeared in: AIIMS Raipur NO - 2019 (Shift-1)

Explanation

Red blood cells (erythrocytes) in a healthy adult have a finite lifespan, averaging about 120 days.
This duration is due to the wear and tear they endure while circulating and transporting oxygen.
Mature RBCs lack a nucleus and other organelles, which prevents them from repairing themselves, leading to eventual degradation.
After approximately 120 days, they become fragile and are removed from circulation by macrophages, mainly in the spleen and liver.

Option A: 250 days is more than double the actual average lifespan of a human red blood cell. No human blood cell has such a long lifespan.
Option B: 180 days (approximately 6 months) is significantly longer than the correct average lifespan of an RBC.
Option C: 50 days is too short for the average lifespan of an adult RBC. A lifespan this short would be indicative of a pathological condition like hemolytic anemia.

Clinical Relevance

Nursing practice connection: Knowing The average lifespan of red blood cells (erythrocytes) in the human body helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Understanding the 120-day lifespan is crucial for managing blood disorders. In hemolytic anemias, the RBC lifespan is drastically shortened, leading to anemia, jaundice, and splenomegaly.
The lifespan of RBCs is the basis for the recommended interval between whole blood donations, which is typically around 12 weeks (84 days) to allow the donor's body to replenish its red cell volume.
The HbA1c test, used to monitor long-term blood glucose control in diabetics, measures glucose attached to hemoglobin and provides an average blood sugar level over the preceding 2-3 months, which corresponds to the RBC lifespan.

How to Approach the Question

This is a direct factual recall question.
Identify the core concept being asked: the 'average lifespan' of 'Red blood cells'.
Access your knowledge base of hematology.
Recall the specific, standard value for the lifespan of an erythrocyte.
Compare this recalled value (120 days) with the given options.
Select the option that matches the correct value.

Concept Tested & Keywords

Concept Tested: The average lifespan of red blood cells (erythrocytes) in the human body.
Stem keywords: average lifespan, Red blood cells
Lead-in keywords: What is

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