Question

What is Ferritin?

• A. It is an iron storage protein in muscle fibers, liver cells and macrophages of the spleen and liver. Iron detaches from transferrin and attaches to ferritin.
• B. It is a non-iron portion of heme which is converted to biliverdin.
• C. It is plasma protein which transfers free iron into the blood stream.
• D. It is an iron-containing molecule which transports oxygen from the blood stream to the tissues.

Hint:

Remember the key proteins in iron metabolism:

\textbf{Hemoglobin}: Oxygen \textbf{transport} in blood.
\textbf{Transferrin}: Iron \textbf{transport} in blood.
\textbf{Ferritin}: Iron \textbf{storage} in cells. \end{itemize}

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question asks for the definition of ferritin, a key protein involved in iron metabolism.

Step 2: Detailed Explanation of Options:
- Statement 1: This is the correct definition. Ferritin is the primary intracellular protein for iron storage. It is found in most tissues, but particularly in the liver, spleen, and skeletal muscle. Iron is transported in the blood by transferrin, and when it reaches a cell for storage, it is released from transferrin and taken up by ferritin.
- Statement 2: This describes the breakdown of the heme group from hemoglobin. The iron is removed, and the remaining porphyrin ring is converted to biliverdin, which is then reduced to bilirubin.
- Statement 3: This describes Transferrin, the main plasma protein that transports iron through the blood.
- Statement 4: This describes Hemoglobin, the protein in red blood cells that contains iron in its heme groups and is responsible for transporting oxygen.

Step 3: Final Answer:
The most accurate description of ferritin is that it is the main iron storage protein inside cells. Therefore, option (A) is correct.