Detailed Study of Blood Cells
Blood cells are the main components of blood in a living body. Blood can be defined as a circulating fluid that is constantly providing our body with oxygen and nutrition. The consistency of blood is mostly in the liquid form and there are numerous proteins and cells suspended in blood. Hence, the entire texture of blood tends to be a bit thicker than the consistency of pure water. There are about 5 litres of blood in an average person.
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There is a liquid known as plasma that is another major constituent of blood. Plasma is rich in protein that allows the blood to transport, clot, and take substances through the system along with performing some other functions as well. The plasma in the blood is also pretty rich in nutrients such as glucose. In this article, students will learn about blood and the origin of blood cells along with some other details.
What are Blood Cells?
A major component in the blood is the blood cells. There are 3 different types, known as red blood cells, white blood cells, and platelets. The blood is transported and conducted with the help of blood vessels such as arteries and veins.
By looking at a picture of blood, students will be able to study the entire structure and read all about the related details as well. In certain cases, the blood might have some clotting issues in the blood vessels. In case the blood vessels are smooth, the clotting factors can easily be tuned.
Different Blood Conditions
There are different medical conditions related to the blood inside a living body. Some of these conditions include haemorrhage, hematoma, leukaemia, multiple myeloma, lymphoma, etc. These conditions have a pretty serious nature and can lead to the loss of lives. There are some other conditions such as anaemia, hemolytic anaemia, hemochromatosis, sickle cell disease, bacteremia, malaria, thrombocytopenia, DIC or Disseminated Intravascular Coagulation, Leukopenia, Hemophilia, Myocardial Infarction, and many other such conditions.
What are Blood Vessels?
Blood vessels can be defined as the channels or distributaries through which blood is transported throughout the entire body. There are three sections of blood vessels and they are arteries, capillaries, and veins. The main function of arteries is to take the blood away from the heart and transport it. The capillaries act as the connection between the main vessels and help in the process of transportation. Veins on the other hand carry all the blood towards the heart. This picture of blood vessels provides a detailed explanation of the three different types.
What are the Different Types of Blood Cells?
There are three different types of blood cells in the body and they make up almost half of the blood composition. Here is a picture of blood cells to clear the topic better.
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Different Blood Cells in the Body
Red Blood Cells
Red blood cells are also known as erythrocytes. These are the most abundant ones of the blood cells in the human body. These account for about 40-45% of the entire blood in the body. The shape of the red blood cells is biconcave and it is round as well as flat. The disc diameter tends to be about 6.2-8.2 µm and there is no nucleus present in the red blood cells. RBCs are rich in haemoglobin and provide a red colour in the blood. Red blood cells tend to last up to 4 months or 120 days in total before new formation takes place. Males produced 4.3-5.9 million/mm3 of RBCs and Females produced 3.5-5.5 million/mm3 of RBCs.
Some of the main functions of red blood cells include the transportation of oxygen from the lungs to other cells in the body. These cells also help in picking up CO2 from other tissues so that it can be unloaded in the lungs.
White Blood Cells
These cells form just about 1% in total of the blood in the body. These cells are responsible for the immune system of the body and hence are responsible for protecting the body against certain foreign substances as well as infections. The creation of white blood cells happens in the bone marrow. The different types of white blood cells include neutrophils, Eosinophils, Basophils, Lymphocytes, and Monocytes. The main functions of blood cells that are white are to kill bacteria and other viruses that enter the body and to provide the body with proper immunity.
Platelets
Thrombocytes or platelets are the third component of the blood cells. There is no nucleus present in the platelets. After careful study of a picture of blood circulation in human body, students will be able to learn more about platelets. These are small fragments of the cells in the bone marrow. There are about 150,000–400,000 platelets present in a microliter of human blood. The main functions of platelets are to clot the blood. These cells also help in promoting other mechanisms of blood clotting. These also help with the secretion of chemicals that attract monocytes and neutrophils to different inflammatory sites.
Conclusion
The above-mentioned article attempts to provide a detailed explanation of the blood cells that are present in the human body. Students can read the article and study the picture of blood cells in order to know more.
FAQs on Blood Cells
1. What are the main components of human blood?
Human blood is a specialised connective tissue composed of two main components: Plasma and Formed Elements. Plasma is the liquid matrix, making up about 55% of the blood, and consists of water, proteins, hormones, and salts. The Formed Elements, which constitute the remaining 45%, are the blood cells. These include Red Blood Cells (RBCs), White Blood Cells (WBCs), and Platelets.
2. What are the three main types of blood cells found in the body?
The three main types of blood cells, also known as formed elements, are:
- Red Blood Cells (RBCs or Erythrocytes): These are the most abundant cells responsible for transporting oxygen.
- White Blood Cells (WBCs or Leucocytes): These cells are a critical part of the immune system, defending the body against infections and diseases.
- Platelets (Thrombocytes): These are not true cells but cell fragments that play a vital role in blood clotting.
3. What is the primary function of Red Blood Cells (RBCs) and why are they red?
The primary function of Red Blood Cells (RBCs) is to transport oxygen from the lungs to all the tissues and organs of the body, and to carry carbon dioxide back to the lungs for exhalation. RBCs are red because they contain a large amount of a protein called haemoglobin. This iron-rich protein binds with oxygen, and it is the iron component that gives blood its characteristic red colour.
4. How do Red Blood Cells and White Blood Cells differ in structure and function?
Red Blood Cells (RBCs) and White Blood Cells (WBCs) differ significantly in their structure and roles:
- Function: RBCs are responsible for oxygen transport, while WBCs are key to the immune system and fighting infections.
- Nucleus: Mature mammalian RBCs are anucleated (lack a nucleus) to maximise space for haemoglobin. In contrast, all WBCs have a prominent nucleus.
- Quantity: RBCs are far more numerous, with about 4.5-5.5 million cells per microlitre of blood, whereas WBCs range from 4,000 to 11,000 cells per microlitre.
- Shape: RBCs have a distinct biconcave disc shape, which increases surface area for gas exchange. WBCs have an irregular, amoeboid shape, allowing them to move through tissues.
5. What are the different types of White Blood Cells (WBCs) and their specific roles?
White Blood Cells are classified into two main categories, granulocytes and agranulocytes, which are further divided into five specific types:
- Neutrophils: The most common type of WBC, they are phagocytic cells that engulf and destroy pathogens like bacteria.
- Lymphocytes: These are crucial for adaptive immunity and include B-cells (which produce antibodies) and T-cells (which destroy infected cells).
- Monocytes: The largest WBCs, they differentiate into macrophages in tissues and perform phagocytosis of cellular debris and pathogens.
- Eosinophils: They fight parasitic infections and are involved in allergic reactions.
- Basophils: The least common type, they release histamine and other mediators during allergic reactions and inflammation.
6. Why do mature mammalian Red Blood Cells not have a nucleus?
Mature mammalian Red Blood Cells lack a nucleus and other organelles like mitochondria for a crucial reason: to maximise intracellular space for haemoglobin. By removing the nucleus, the cell can pack in more haemoglobin molecules, thereby increasing its oxygen-carrying capacity. This adaptation makes oxygen transport highly efficient. The absence of mitochondria also ensures that the RBC does not consume the oxygen it is transporting through aerobic respiration.
7. What is the function of platelets or thrombocytes in the body?
The primary function of platelets (thrombocytes) is to initiate blood clotting, a process also known as coagulation. When a blood vessel is damaged, platelets rush to the site, stick to the wound, and form a temporary plug. They also release chemical signals that activate a cascade of clotting factors, leading to the formation of a stable fibrin clot. This clot seals the wound, prevents excessive blood loss, and allows the tissue to heal.
8. Where are blood cells produced in the human body?
All blood cells are produced in the bone marrow, the soft, spongy tissue found inside bones. This process is called haematopoiesis. In adults, haematopoiesis primarily occurs in the bone marrow of the pelvis, vertebrae, ribs, and sternum. All three types of blood cells—Red Blood Cells, White Blood Cells, and Platelets—originate from a common type of cell known as a haematopoietic stem cell.
