Types of White Blood Cells

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Blood is a fluid connective tissue which supplies oxygen and the mineral resources and carries out the waste products and carbon dioxide throughout the body. It is made up of different types of blood cells, which are produced in the bone marrow. It is about 80% water and 20% solids.

Types of Blood Cells:

The blood is made up of four different types of cells:

  1.  Red blood cells (RBC)

  2.  White blood cells (WBC)

  3.  Plasma

  4.  Platelets

The composition of blood is as follows, ~55% of plasma and ~45% of blood cells. Now we will discuss briefly about WBC.

What are White Blood Cells?

WBC is a type of blood cell which helps us to fight against diseases. These WBC are produced by stem cells in the bone marrow and it is found in the blood and lymph tissue. WBC are also called leukocytes.

The lifespan of WBC is about 13 to 20 days. After this, they are destroyed inside the lymphatic system. The normal white blood cell count in blood is 4,500 to 11,000 per microlitre.

White Blood Cells Function: 

WBC are a part of the immune system, if there is a decrease in the immune power, then the body releases the WBC. The main function of these cells is to protect the body from getting affected by foreign particles. Whenever an infection or foreign particle invades the body, the WBC builds up the antibodies and attacks the germs to destroy it.

Types of White Blood Cells and their Function:

There are three different types of white blood cells,

1.  Granulocytes: 

Granulocytes are a type of WBC, which has small granules made up of proteins. These are further divided into three types, and they are:

a. Basophils: Basophils helps to provide immune responses to parasitic infections. In addition to that, it has the following functions:

  1. Prevents blood clotting: Basophil contains a substance called heparin, which is a blood-thinning substance, this avoids clotting of blood inside the body.

  2. Mediates allergic reactions: When an immune system is exposed to an allergen, the basophil releases a substance called histamine which helps to kill the allergens, it is well known for its role to fight against asthma.

b. Eosinophils: Eosinophils are the special cells inside the immune system which are involved in inflammatory and anti-parasitic responses.

c. Neutrophils: Neutrophils help to heal damaged tissues, it also helps to fight against bacterial or viral infections.

Difference Between Basophils, Eosinophils and Neutrophils:






Helps to diagnose autoimmune disease or blood-related disorders

Helps to fight against allergies and diseases

Provide an immune response against any foreign particle attack


Multi lobed nucleus

Bean shaped nucleus

Two or bilobed nucleus

Life span

Life span is about 60-70 hours

Life span is about 8-12 hours

Life span is about 5 to 90 hours


Diameter is of 10-14 micrometres

Diameter is about 12-17 micrometres

Diametre is about 8.86 micrometres



Leukopenia (low level) and Eosinophilia(High level) 

Leukocytosis (high level) and Neutropenia (low level)

2. Lymphocytes: 

The lymphocytes are further divided into three types:

  1. B cells: The B cells are also referred to as B lymphocytes, which produce antibodies in the immune system.

  2. T cells: The T cells are also referred to as T lymphocytes, which helps to recognize and remove the infection-causing pathogens.

  3. Natural killer cells: These cells are responsible for attacking and killing the pathogens, it also kills cancerous cells.

Difference between B cells and T cells:


B cells

T cells

Site of maturation

It originates and matures in the bone marrow.

It originates in the bone marrow and matures in the thymus.

Also called

B lymphocytes.

T lymphocytes.


Present outside the lymph nodes.

Present inside the lymph nodes.

Life span

Shorter life span.

Larger life span compared to B cells.

3. Monocytes:

Monocytes make up around 2 to 8% of the WBC, which helps to fight against chronic infections.

WBC Normal Range:

The WBC normal range is based on age.


Normal Range(Per Cubic Millimetre)


13,000 - 38,000

2 week old baby

5,000 - 28,000


4,500 - 11,000

What Happens When a Person Has a High White Blood Cell Count?

If the WBC count increases in the body, then may lead to the disease leukocytosis. Below are the medical conditions indicated dues to high white blood cell count:

  1. Asthma attack

  2. Heart attack

  3. Rheumatoid arthritis, inflammatory bowel diseases

  4. Leukemia

What Happens When a Person Has a Low White Blood Cell Count?

If the human body is producing lower numbers of  WBC it leads to a disease called leukopenia.

Conditions for leukopenia are as follows:

  1. Bone marrow disorders

  2. Vitamin B-12 deficiency

  3. Autoimmune conditions, HIV

Hence we can conclude that blood cells play an important role in our life. It protects our body by keeping a track of foreign bodies. They also supply oxygen to cells and tissues and provide essential nutrients. Blood cells help to keep our body clean by removing the waste products through the kidney.

FAQ (Frequently Asked Questions)

1. What are the Foods that Increase the Count of White Blood Cells?

Answer: Consuming the foods which are rich in vitamin C will increase the WBC count. The foods which are rich in vitamin C are citrus fruits which include, grapefruit, oranges, lemon, bell peppers.

2. What are the Symptoms of Low White Blood Cell Count?

Answer: Below are the symptoms of low white blood cell count in a human body -

  1. Having repeated fevers and infections.

  2. Bladder infections may make you urinate more often or make it painful to pass urine.

  3. Lung infections which cause coughing and you may feel difficulty in breathing.

  4. Mouth sores.

  5. Sinus infections and a stuffy nose.

  6. Skin infections.