Which component found inside your capillaries is primarily responsible for carrying oxygen to your heart?

• A. Platelets (thrombocytes)
• B. Red blood cells (erythrocytes)
• C. White blood cells (leukocytes)
• D. Plasma proteins

Answer: (B)

Verified step by step guidance

1. Understand the function of each component listed in the problem: Platelets (thrombocytes) are involved in blood clotting, White blood cells (leukocytes) are part of the immune system, Plasma proteins help with transport and maintaining osmotic balance, and Red blood cells (erythrocytes) are responsible for oxygen transport.
2. Recall that oxygen is carried in the blood by binding to hemoglobin, a protein found inside red blood cells (erythrocytes). Hemoglobin has a high affinity for oxygen and facilitates its transport.
3. Consider the role of capillaries: Capillaries are the smallest blood vessels where gas exchange occurs. Oxygen carried by red blood cells is delivered to tissues, including the heart, through capillaries.
4. Eliminate incorrect options based on their primary functions: Platelets are not involved in oxygen transport, White blood cells are focused on immune defense, and Plasma proteins do not directly carry oxygen.
5. Conclude that the correct answer is Red blood cells (erythrocytes), as they are the primary component responsible for carrying oxygen to the heart and other tissues.