Normal range of white blood cells (WBCs) per microliter of blood is:

White blood cells (WBCs), also known as leukocytes, are an essential component of the immune system. They defend the body against infections, foreign particles, and harmful microorganisms. WBCs are produced in the bone marrow and circulate through the bloodstream, lymphatic system, and tissues to detect and respond to threats.

The normal range of white blood cells in a microliter (µL) of blood is approximately 4,500 to 10,000. This range represents healthy immune function in humans. Counts below this range, called leukopenia, can make a person more susceptible to infections, while counts above this range, known as leukocytosis, may indicate infections, inflammation, or other medical conditions.

There are several types of WBCs, each with specialized functions:

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  Neutrophils: fight bacterial infections

  
  


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  Lymphocytes: produce antibodies and regulate immune response

  
  


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  Monocytes: remove dead cells and pathogens

  
  


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  Eosinophils: combat parasites and allergic reactions

  
  


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  Basophils: release histamine during inflammation

  
  

WBC count is a crucial parameter in hematology, often measured through a complete blood count (CBC) test. Monitoring WBCs helps understand immune system health, detect infections, and track conditions like autoimmune disorders or blood cancers.

Maintaining a healthy WBC count involves balanced nutrition, regular exercise, adequate sleep, and avoiding factors that weaken immunity, such as chronic stress or exposure to toxins.

In summary, the normal WBC range of 4,500 to 10,000 per microliter of blood reflects a properly functioning immune system. Understanding WBCs is a fundamental part of biology and everyday science, as it shows how the body protects itself from harmful agents and maintains overall health.