👉 The four fundamental fluids in nature are water, air, oil, and blood. Water is the most abundant and essential fluid, comprising about 71% of Earth's surface and playing a crucial role in all biological processes. Air, consisting mainly of nitrogen and oxygen, is vital for respiration and acts as a medium for gas exchange. Oil, a mixture of hydrocarbons, is non-polar and serves as an energy source and lubricant, while blood, a complex fluid composed of plasma, red and white blood cells, and platelets, is responsible for transporting oxygen, nutrients, hormones, and waste products throughout the body. These fluids interact and exchange components, maintaining life-sustaining processes in all living organisms.
