Final answer:
A normoblast would not normally be found in circulating blood; it's an immature red blood cell found in the bone marrow. Neutrophils, erythrocytes, and electrolytes are all normal components of circulating blood. Mature erythrocytes are anucleate and have a lifespan of approximately 120 days.
Step-by-step explanation:
The component that would NOT normally be found in circulating blood is the normoblast. A normoblast, also known as an erythroblast, is an immature red blood cell (erythrocyte) that typically resides in the bone marrow and is not usually found in the circulating blood. In contrast, neutrophils, erythrocytes, and electrolytes are normal constituents of circulating blood. Neutrophils are a type of white blood cell that play a key role in the immune response, erythrocytes are responsible for transporting oxygen and carbon dioxide, and electrolytes are minerals that help maintain the body's fluid balance and conduct electrical impulses.
For statement 11 about circulating erythrocytes, the true statement is 'a. They have no nucleus.' Mature erythrocytes lack a nucleus and mitochondria and have a lifespan of about 120 days on average, rather than just 4 days.