What are Red Blood Cells (RBCs)?

RBCs, or erythrocytes, are one of the components of blood. (The others are plasma, platelets and white blood cells.)

What are Red Blood Cells (RBCs)?
  • About Red Blood Cells (RBCs):
  • RBCs, or erythrocytes, are one of the components of blood. (The others are plasma, platelets and white blood cells.) 
  • Function:
    • They deliver oxygen to the tissues throughout the human body. 
    • Oxygen turns into energy, and tissues release carbon dioxide.
    • RBCs also transport carbon dioxide back to the lungs to be exhaled.
  • Where are RBCs made?
    • They are made in the bone marrow.
    • They typically live for about 120 days, and then they die.
  • Hemoglobin:
    • RBCs contain a protein called hemoglobin, which binds to oxygen in the lungs, forming oxyhemoglobin.
    • Hemoglobin also helps carry carbon dioxide back to the lungs as carbaminohemoglobin.
  • Shape:  
    • RBCs are biconcave, disc-shaped cells with a dimple in the center on both sides. This unique shape increases the surface area of the cell, allowing for efficient gas exchange.
    • It is covered with a membrane composed of lipids and proteins and lacks a nucleus.
  • What does a low RBC count mean?
    • A low RBC count, known as anemia, can cause fatigue, shortness of breath, dizziness and other symptoms. If untreated, anemia can lead to serious complications. 
    • In many cases, anemia occurs when people don’t eat a nutrient-rich diet.
    • It can also be caused by pregnancy and certain medical conditions such as bleeding disorders and kidney disease.
    • Choosing foods that are rich in iron and other vitamins and minerals can help raise the RBC count. 

 

What is Sickle cell anemia?

  • It is an inherited blood disorder.
  • It affects hemoglobin, the molecule in red blood cells that delivers oxygen to cells throughout the body. 
  • People with this disease have atypical hemoglobin molecules called hemoglobin S, which can distort red blood cells into a sickle, or crescent, shape.
  • These sickle cells also become rigid and sticky, which can slow or block blood flow.
  • What causes it?
    • The cause of Sickle cell disease is a defective gene called a sickle cell gene.
    • A person will be born with sickle cell disease only if two genes are inherited—one from the mother and one from the father.
  • Treatments:
    • The only cure for this disease is bone marrow or stem cell transplantation.
    • However, there are treatments that can help relieve symptoms, lessen complications, and prolong life.

 


Q1) What is bone marrow?

Bone marrow is a soft, spongy tissue found in the cavities of certain bones in the human body. It is a crucial part of the human circulatory system and plays a vital role in blood formation, immune function, and the storage of fat.

Source: Red blood cells exposed to oxygen deficiency protect against heart attack

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