Difference Between RBC and WBC

The difference between RBC and WBC is mainly due to the following properties like colour, morphology and function. RBC stands for Red blood cell. WBC stands for white blood cell.

Colour: The terms (red blood cell and white blood cell) clear the colour difference. The reason behind the red colour of the RBCs is due to the iron atom present in the haemoglobin pigment. The white blood cells are colourless because they lack any coloured pigment.

Morphology: The structure of red blood and white blood cells have a characteristic shape. Red blood cells resemble a shallow bowl, as they have a flattened centre and elevated margin. White blood cells seem like amoeboid cells, as they have an irregular margin.

Function: Both red blood and white blood cells belong to the circulatory system, in which the former facilitates the gaseous exchange between the cardiovascular system and the latter provides resistance against the infection and pathogen attack.

Content: RBC Vs WBC

1. Comparison Chart
2. Definition
3. Key Differences
4. Similarities
5. Conclusion

Comparison Chart

Properties	RBC	WBC
Stands for	Red Blood Cell	White Blood Cell
Alternative name	Erythrocytes	Leukocytes
Shape	Biconcave, disc-like	Irregular, amoeboid-like
Diameter	7.5 µm	15 µm
Colour	Red coloured due to haemoglobin pigment	Colourless and does not contain such pigment molecules
Method of production	Erythropoiesis	Leucopoiesis
Regulatory hormone	Erythropoietin hormone	Leucopoietin hormone
Origination	Bone marrow	Bone marrow, lymph nodes, spleen etc.
Nucleus	Absent	Present
Motility	Non-motile	Motile
Life span	100-120 days	12-20 days
Constitution in blood	36-50%	Around 1%
Circulatory movement	Moves between the cardiovascular system	Moves between the cardiovascular and lymphatic system
Cell count/µl of blood	4.7-6.1 million/µl	4500-11000/µl
When cell count increases	Leads to Polycythaemia	Leads to Leukocytosis
When cell count decreases	Leads to anemia	Leads to Leukopenia
Measurement	Can be measured by using haemocytometer via RBC pipette	Can be measured by using haemocytometer via WBC pipette
Number increments	Cell count of RBCs increases by the uptake of iron-rich food, doing exercise etc.	Cell count of WBCs increases by any kind of foreign attack
Types	It has no subtypes	These are of five kinds: neutrophil, eosinophil, basophil, lymphocytes and monocytes
Functional role	Helps in circulation of oxygenated blood and nutrients throughout the body	Provides protection against the pathogens and removes the infected cells via phagocytosis

Definition of RBC

RBC is an acronym of the term “Red Blood Cell”. It refers to the component of blood or a type of blood cells, which originates from the bone marrow, attains maturity for at least seven days and finally enters the bloodstream to transport O₂ and CO₂ into and out of the body.

The formation of red blood cells is regulated by a hormone “Erythropoietin” produced primarily by the juxtaglomerular cells of the kidney through a process “Erythropoiesis”.

“Reticulocytes” are immature RBCs. Oppositely, “Erythrocytes” are the mature RBCs. The structure of mature RBCs lacks a nucleus and other cell organelles like ribosomes, mitochondria etc., and they can modify their shape.

The red blood cells move freely in the bloodstream, and they can flexibly pass through the small blood vessels and capillaries. RBCs possess red colour due to the presence of protein pigment “Haemoglobin”.

Haemoglobin is an oxygen-carrying pigment, which contains four iron atoms that bind to the four oxygen molecules. Therefore, haemoglobin is the major component of red blood cell that imparts a red colour and facilitates the transportation of oxygenated blood from the lungs to the other body parts and carbon dioxide from the other body parts back into the lungs.

Mutation in the haemoglobin gene can cause abnormal disease like sickle cell anaemia, where the oval shape of RBCs changes to sickle-like. “Haematocrit” is a standard unit that measures the volume of RBCs.

The method determining the RBC ratio in the blood is known as the “Haematocrit test”. The “Homeostasis” is an equilibrium state in which the degradation and production occur simultaneously, or it maintains the RBCs concentration.

Definition of WBC

WBC is an abbreviation of the term “White Blood Cell”. It refers to the component of blood or a type of blood cells, which also originates from the bone marrow and attains maturity in the organs like lymph nodes, spleen and thymus gland.

The production of white blood cells is regulated by a hormone “Leucopoietin” that stimulates myeloid cells’ production through a process “Leucopoiesis”.

Based on cell lineage, myeloid and lymphoid cells are the two common types of leucocytes. A myeloid stem cell produces monocytes and myelocytes (neutrophils, eosinophils and basophils), while a lymphoid stem cell produces lymphocytes.
Similarly, based on specific cytoplasmic granules, granulocytes and agranulocytes are the two common types of leucocytes. The granulocytes involve neutrophils, eosinophils and basophils and possess distinct granules in the cell cytoplasm. In contrast, non-granulocytes include monocytes and lymphocytes, which consist of non-distinct or non-functional granules.

• Neutrophils are phagocytic cells. They become activated against acute infection due to bacterial and fungal attack.
• Eosinophil stimulates in counter to any parasitic infections.
• Basophils target the allergic sites, especially in the case of type-1 hypersensitivity.
• Monocytes present the antigenic fragments to the T-cell and target the chronic infection site.
• Lymphocytes are of two kinds. B-lymphocytes produce antibodies to neutralize the antigenicity or block the pathogen invasion, and T-lymphocytes activate in counter to the viral and chronic infection.

Similarities

1. Both RBC and WBC are the kinds of blood cells, which are the universal constituents of blood.
2. Haematocrit test is a complete blood count test that can measure the cell concentration of RBC (represented as haematocrit) and the concentration of WBC (represented by the Buffy layer).
3. Both RBC and WBC are produced by the haematopoietic stem cells, and the process is commonly called haematopoiesis.
4. The cell number of both red blood and white blood cells can be determined using a Neubauer counting chamber or haemocytometer under the microscope.

Conclusion

Therefore, we can conclude that RBCs and WBCs are a part of the circulatory system, which perform distinct functions to boost the body’s immunity and metabolism.