Which type of cell makes up about 90% of the alveolar surface?

A) Ciliated simple squamous epithelial cells
B) Type I pneumocytes
C) Type II pneumocytes
D) Macrophages

Alveolar Surface

The inner surface area of the alveoli, tiny sacs in the lungs where gas exchange between the air and blood takes place.

Type I Pneumocytes

Thin cells that line the alveoli of the lungs and are involved in the process of gas exchange between the lungs and the blood.

Type II Pneumocytes

are specialized cells in the alveoli of the lungs, responsible for the production and secretion of pulmonary surfactant to decrease surface tension.