What are the solutes found in blood?

• A. Platelets and plasma cells.
• B. Hormones and enzymes.
• C. Nutrients, wastes, gases, and electrolytes.
• D. Red blood cells and white blood cells.

Answer: (C)

Solutes are the dissolved substances in blood plasma—the things the blood carries in a dissolved form rather than as cells. The main categories of these dissolved substances include nutrients (like glucose and amino acids), wastes (such as urea), gases (oxygen and carbon dioxide), and electrolytes (sodium, potassium, chloride, calcium, etc.). These solutes are essential for delivering energy and materials to tissues, removing waste, maintaining acid-base balance, and supporting nerve and muscle function.

The other options describe cellular components or more specific molecules rather than the broad dissolved substances in plasma. Platelets and plasma cells are cells involved in clotting and immune responses, not solutes. Hormones and enzymes can be present in blood as solutes, but they are specific types of solutes rather than the broad category of dissolved substances that includes nutrients, wastes, gases, and electrolytes. Red and white blood cells are also cellular components, not solutes.