Final answer:
The observed cell without a nucleus and shaped like a disk in human blood is a red blood cell (erythrocyte), which is responsible for transporting oxygen and carbon dioxide throughout the body.
Step-by-step explanation:
Identification of the Blood Cell
- If you observed a cell from human blood that has no nucleus and is shaped like a disk, then it is likely an erythrocyte, commonly known as a red blood cell (RBC). Red blood cells are specialized for the transport of oxygen thanks to the protein hemoglobin, which binds oxygen molecules. Unlike other cells in the body, red blood cells lack a nucleus at maturity, which allows for more space to carry hemoglobin. They have a distinctive biconcave shape that facilitates the exchange of oxygen and carbon dioxide.
Role of Red Blood Cells
- Red blood cells are essential for life as they deliver oxygen to cells throughout the body and remove carbon dioxide, a waste product of cellular metabolism. They are produced from stem cells in the bone marrow and are designed to function efficiently in oxygen transport. The lack of a nucleus and other organelles in red blood cells limits their lifespan to about 120 days, after which they are replaced by new cells.
Incorrect Alternatives
- Other cell types in the blood include white blood cells (leukocytes), which are part of the immune system and contain nuclei, and platelets (thrombocytes), which are fragments of cells important for blood clotting. Neurons are nerve cells responsible for transmitting nerve impulses and are not found in the blood.