Red Blood Cells

Red Blood Cells are responsible for the transport of oxygen throughout the body. They are one of the three main classes of blood cells, the other two are white blood cells and platelets. Red blood cells are named so because they contain the iron-containing protein called the haemoglobin which imparts the characteristic red colour to the cells.

They are present in the highest numbers in the blood. This is why they are responsible for the characteristic red colour of the blood. In this article, we will look into the diagram of red blood cells, structure, and function in detail.

What are Red Blood Cells?

Red Blood Cell are also known as erythrocytes. They are the most abundant cells of the blood circulatory system i.e. around 40% to 45% volume of the blood consists of red blood cells. They have a unique biconcave, disc-like appearance. They do not have a functional nucleus and mitochondria in them due to which they have a very limited lifespan i.e. around 120 days.

They are produced in the bone marrow by the process of erythropoiesis and get destroyed in the spleen or in some cases the liver by the process of erythrocyte apoptosis. They consist of iron-containing haemoglobin that is responsible for carrying and transporting oxygen throughout the body.

Diagram of Red Blood Cells

A mature RBC diagram is given below:

Red Blood Cells Structure

The structure of RBCs is as follows:

• The red blood cells are biconcave and disc-shaped i.e. they are round like a disc with depression in the centre.
• They lack nuclei and many other functional cell organelles. This feature allows them maximum space to carry haemoglobin.
• Red blood cells have a flexible cell membrane that allows them to fold or bend to pass through narrow blood vessels.
• They have certain enzymes like carbonic anhydrase and some cytoskeletal proteins like actin other than the haemoglobin in their cell cytoplasm.
• Biconcave shape provides a large surface area-to-volume ratio helping in efficient oxygen transport.

Features of Red Blood Cells

The following are some of the characteristic features of the RBC:

1. They have a biconcave, disc-shaped appearance.
2. The biconcave shape of the RBC provides a maximum surface-to-volume ratio for efficient transport of oxygen.
3. They contain haemoglobin that binds with oxygen to facilitate its transport throughout the body.
4. The red colour of blood is due to the iron-containing heme group group of the haemoglobin.
5. The normal count of RBC in the human body is 4.5 to 6.5 million cells per microliter of blood in males and 4.0 to 5.5 million cells per microliter of blood in females.
6. They eject out their nucleus and other cell organelles (the process of enucleation) during their developmental phase in bone marrow.
7. As they lack mitochondria the RBCs depend only on glycolysis for energy generation.
8. They are highly flexible cells to ensure movement through narrow passages of the blood vessels.
9. After their destruction, the broken components of the RBCs are used again for the synthesis of new RBCs.
10. They also help in the transport of carbon dioxide from tissues to the lungs.

Functions of Red Blood Cells

Following are some of the crucial functions of the RBCs:

• RBCs are responsible for the transport of oxygen throughout the body.
• They also help in the removal of carbon dioxide from the body.
• RBCs maintain the blood’s pH levels by regulating the acid-base balance.
• They also help in the regulation of blood volume by increasing or decreasing their numbers as per need.
• RBCs help to regulate blood flow and blood pressure by contracting and dilating the blood vessels.

Factors Affecting the Function of RBC

There are certain factors responsible for the proper functioning of the RBCs, which are:

• Oxygen levels in the atmosphere i.e. low oxygen levels lead to increased production of RBC to compensate.
• The concentration of haemoglobin in the RBCs can affect the oxygen-carrying capacity of the blood.
• Deficiency of nutrients like iron, vitamin B12, and folate can cause iron deficiency anaemia that leads to impaired oxygen transport.
• Diseases or disorders like sickle cell anaemia, thalassemia, etc. can affect RBC structure and its function.
• Toxic substances like carbon monoxide can impair RBC’s functioning.

Conclusion – Red Blood Cells

Red blood cells (RBCs) are a component of blood that transport gases and nutrients throughout the body. Their main function is to carry oxygen from the lungs to the body’s tissues. They also transport carbon dioxide back to the lungs to be exhaled. Red blood cells make up 40% of the blood in the bloodstream. They are small, disc-shaped cells with an indentation in the middle, which makes them look a little bit like a doughnut. Because they are so small, they can fit through the tiny capillaries where the exchange of oxygen for carbon dioxide typically occurs.

FAQs on Red Blood Cells: Diagram and Features

What is the Function of Red Blood Cells?

The main function of the red blood cells in the body is to transport oxygen throughout the body.

How do you Increase Red Blood Cells?

The red blood cell count can be increased by a regular intake of iron, vitamin B12, and folate.

How many Days Red Blood Cells Live?

A red blood cell in its mature form can survive up to 120 days in the circulatory system.

What is the Other Name of Red Blood Cell?

The other name of the red blood cell is Erythrocyte. This word comes from the Greek words “erythrose” meaning “red” and “cyte” meaning “cell”.

What is the Red Blood Cells Normal Range?

The normal count of RBC in the human body is 4.5 to 6.5 million cells per microliter of blood in males and 4.0 to 5.5 million cells per microliter of blood in females.

What are the Identifying Features of RBC?

The main identifying feature of RBC is its biconcave, disc-shaped structure and the absence of a nucleus in it.

How many Haemoglobin in one RBC?

In a single RBC, there are approximately around 260 million haemoglobin molecules present.