Red blood cells

Definition

Red blood cells (RBCs), also known as erythrocytes, are the most abundant cells in the blood and are responsible for transporting oxygen from the lungs to tissues throughout the body. They contain hemoglobin, a protein that binds to oxygen.

5 Must Know Facts For Your Next Test

1. Red blood cells are biconcave in shape, which increases their surface area for gas exchange.
2. They have a lifespan of about 120 days in the human body.
3. RBCs lack a nucleus and most organelles, allowing more room for hemoglobin.
4. Hemoglobin within RBCs is crucial for oxygen transport and gives blood its red color.
5. Red blood cell production occurs in the bone marrow through a process called erythropoiesis.

Review Questions

• What is the primary function of red blood cells?
• Describe the shape of red blood cells and explain how it aids their function.
• Where does red blood cell production take place?

Related terms

Hemoglobin:

A protein in red blood cells that binds to oxygen and transports it to tissues.

Erythropoiesis: The process by which new red blood cells are produced in the bone marrow.

Bone Marrow: The spongy tissue inside bones where red blood cell production occurs.