Final answer:
Plasma proteins, primarily albumin, and electrolytes are the main components responsible for creating the blood's osmotic pressure, with albumin being the most significant contributor.
Step-by-step explanation:
The two components of plasma that create most of the blood's osmotic pressure are plasma proteins and salts (electrolytes). Plasma proteins, especially albumin, are crucial for maintaining osmotic pressure. Albumin, the most abundant plasma protein manufactured by the liver, acts as a transport vehicle for fatty acids and steroid hormones and significantly contributes to the osmotic pressure of blood. It helps hold water inside the blood vessels, thus maintaining blood volume and blood pressure. Salts, or electrolytes, such as sodium, potassium, and chloride, also play key roles in osmotic balance, being closely regulated in the body fluids to ensure proper cell function and overall homeostasis.