Blood: The Body's Transport System
Blood is like a busy highway carrying passengers and cargo to every corner of your body. Red blood cells (erythrocytes) are the oxygen delivery trucks, packed with hemoglobin that bonds with oxygen to form oxyhemoglobin for transport to tissues.
White blood cells (leucocytes) act as your body's security force, surrounding and destroying harmful invaders while producing antibodies to fight infections. Platelets are your emergency repair crew - they rush to wounds and stick together to form clots that stop bleeding.
All these components float in plasma, which is about 90% water mixed with glucose, salts, proteins, and waste products. The circulatory system creates two main loops: deoxygenated blood travels to the lungs through the pulmonary artery, while oxygenated blood returns via the pulmonary vein.
Cool fact: Your blood makes a complete journey through your entire body in just about 60 seconds - that's faster than most jeepney routes in Manila!