Final answer:
Skin leucocytes, also known as white blood cells, are immune cells that respond to chemical attractants released by pathogens and injured cells.
Step-by-step explanation:
Skin leucocytes, also known as white blood cells, are immune cells that are found in the blood. They respond to chemical an attractant released by pathogens and chemical signals from nearby injured cells. These leucocytes play a crucial role in the inflammatory response and immune defense mechanisms of the body.