What does plasma contain that is crucial for blood function?

Plasma is a vital component of blood, constituting about 55% of its overall volume. It serves several important functions, primarily by acting as a transport medium for various substances throughout the body. One of the key aspects of plasma is that it contains a variety of dissolved nutrients and clotting factors.

Dissolved nutrients such as glucose, amino acids, vitamins, and minerals are essential for providing energy and supporting cellular activities. Clotting factors in plasma play a critical role in hemostasis, which is the process of blood clotting that prevents excessive bleeding when there is an injury. These factors work together to facilitate the complex cascade that leads to the formation of a stable clot.

In contrast, other options focus on narrower aspects of blood composition. While hormones and electrolytes are present in plasma, they are not as comprehensive in addressing the full range of substances critical for blood function. The suggestion that plasma primarily contains red blood cells and platelets misrepresents the primary function of plasma, as these components are actually suspended in plasma but are not part of its composition. Lastly, while immune cells and waste products are important components of blood, they do not encompass the crucial functions provided by the dissolved nutrients and clotting factors found in plasma.