Which term describes the components of blood responsible for immune response?

The term that describes the components of blood responsible for immune response is leucocytes, commonly known as white blood cells. These cells play a crucial role in the immune system by identifying and responding to pathogens such as bacteria, viruses, and other foreign invaders. Leucocytes are diverse in their functions, including destroying pathogens, producing antibodies, and regulating immune responses.

Erythrocytes, or red blood cells, are primarily concerned with the transportation of oxygen from the lungs to the body tissues and carbon dioxide back to the lungs. They do not have a role in the immune response.

Platelets, or thrombocytes, are involved in blood clotting and the prevention of bleeding. While they play an essential role in wound healing and repairing blood vessels, they do not directly participate in immune responses.

Hemoglobin is the protein within erythrocytes that binds oxygen for transport. It is not a component that directly engages in immune functions. Therefore, leucocytes are uniquely specialized for immune tasks, making them the correct answer to the question.