What is the primary function of blood in the human body?

The primary function of blood in the human body is to transport and deliver oxygen and nutrients to various cells and tissues. Blood serves as a vital fluid that circulates through the body, allowing oxygen absorbed in the lungs to be distributed to all parts of the body. This oxygen is essential for cellular respiration, which is the process through which cells generate energy.

In addition to oxygen, blood also carries nutrients absorbed from the digestive tract, including sugars, fats, vitamins, and minerals, providing the necessary components for energy production and cellular functions. Moreover, blood plays a crucial role in the transportation of waste products, such as carbon dioxide, from cells to the lungs for exhalation, and other metabolic waste products to the kidneys for excretion.

While other functions, such as temperature regulation and support, are important, they are secondary to the critical role blood plays in transport and delivery.