Final answer:
A septal cell is known as a Type II pneumocyte, which secretes pulmonary surfactant in the alveolar wall of the lungs and prevents alveolar collapse.
Step-by-step explanation:
The cell that is also called a septal cell is b. Type II pneumocyte. These type II alveolar cells are cuboidal epithelial cells located in the alveolar wall of the lungs. These cells play a critical role in the respiratory system by secreting pulmonary surfactant, which reduces the surface tension within the alveoli and prevents the alveolar collapse during exhalation. It's important to note that these cells are distinct from the more numerous type I alveolar cells, which are squamous epithelial cells that constitute a majority of the alveolar surface area and are highly permeable to gases.