What are the main functions of blood in the human body?

Here are the functions of blood:

• Transport of Gases: Blood transports oxygen from the lungs to all body tissues and carries carbon dioxide, a waste product, from the tissues back to the lungs for exhalation. This is primarily done by hemoglobin in red blood cells.
• Transport of Nutrients: It delivers absorbed nutrients like glucose, amino acids, fatty acids, vitamins, and minerals from the digestive tract to cells throughout the body for energy, growth, and repair.
• Transport of Hormones: Blood acts as a medium for transporting hormones secreted by endocrine glands to their target organs, regulating various physiological processes.
• Transport of Waste Products: Metabolic waste products such as urea, uric acid, and creatinine are transported by blood from the tissues to the kidneys for excretion.
• Regulation of Body Temperature: Blood helps regulate body temperature by distributing heat generated by metabolic activity throughout the body and by carrying heat to the skin for dissipation.
• Regulation of pH: Blood contains buffer systems (e.g., bicarbonate buffer system) that help maintain the body's pH within a narrow, physiological range (7.35-7.45).
• Regulation of Fluid and Electrolyte Balance: Blood plasma contributes to maintaining the osmotic pressure and fluid balance between blood and interstitial fluid, as well as distributing electrolytes.
• Protection Against Infection: White blood cells (leukocytes) and antibodies (immunoglobulins) in the blood are crucial components of the immune system, defending the body against pathogens, foreign substances, and diseased cells.
• Protection Against Blood Loss: Platelets and clotting factors in the blood initiate the process of hemostasis, forming blood clots to prevent excessive blood loss from injured vessels.