Which of the following is NOT a way that alveoli are adapted for efficient gas exchange?

Alveoli are small air sacs located in the lungs and are essential for gas exchange. They are specially adapted to maximize the efficiency of this process. One of the key adaptations is their large surface area, which allows for a greater volume of gases to diffuse in and out simultaneously. Thin walls, which are composed of a single layer of epithelial cells, minimize the distance oxygen and carbon dioxide must travel, greatly enhancing diffusion rates. The presence of a large blood supply ensures that oxygen is quickly transported away from the alveoli into the bloodstream and that carbon dioxide is removed efficiently.

High levels of proteins are not a known adaptation of alveoli for gas exchange. While proteins are important in many cellular functions, the primary structures and adaptations of the alveoli focus on surface area, wall thinness, and blood supply. Therefore, the option regarding high levels of proteins does not pertain to their role in facilitating gas exchange.