Final answer:
The beginning of an atherosclerotic plaque is called a fatty streak, which forms when LDLs accumulate and cause inflammation within the artery walls.
Step-by-step explanation:
The beginning of an atherosclerotic plaque is called a fatty streak. This is one of the earliest visible signs of the atherosclerotic process. A fatty streak is formed when low-density lipoproteins (LDLs) accumulate inside the endothelial cells that line the artery walls. This accumulation causes inflammation, which in turn attracts white blood cells leading to plaque formation. As the process continues, a cascade of immune responses causes the plaque to grow, becoming more fibrous and potentially calcified, reducing the elasticity of artery walls and narrowing the artery, which impedes blood flow.