Hemoglobin is a protein found in red blood cells, which are produced in the bone marrow. Here's why:

* Function: Hemoglobin's primary function is to carry oxygen from the lungs to the rest of the body and deliver carbon dioxide back to the lungs.

* Red Blood Cells: Red blood cells are specialized cells that are optimized for this oxygen transport role. They are produced in the bone marrow, which is a soft, spongy tissue found inside bones.

* Production Process: The process of making red blood cells and hemoglobin is complex and involves various steps, including the synthesis of heme (the iron-containing portion of hemoglobin) and globin (the protein component).

While skin cells are important for protecting the body, they do not play a role in producing hemoglobin.