GENERAL HISTOLOGY

Detailed explanation-1: -Simple squamous epithelium lines air sac or alveoli. These squamous epithelial cells are permeable and allow the oxygen from the air to enter the blood in the capillaries of the lung, So, the correct answer is option ‘Squamous epithelium’.

Detailed explanation-2: -Simple squamous epithelia are found in endothelium (lining of blood and lymph capillaries), mesothelium (coelomic epithelium/peritoneum), alveoli of lungs, glomeruli, and other tissues where rapid diffusion is required.

Detailed explanation-3: -Simple squamous epithelium also makes up the alveoli in the lungs (Figure 3), where rapid gas exchange occurs, as oxygen enters the bloodstream through alveolar blood vessels and carbon dioxide exits as waste.

Detailed explanation-4: -Simple squamous epithelial cells are flat and thin enough to allow molecules to pass via diffusion. This cell type is found in the walls of capillaries, linings of the pericardium, and alveoli.

Detailed explanation-5: -Simple squamous epithelia are found in alveoli and capillaries of lungs where gas exchange occurs, kidney glomerulus and tubules where filtration and diffusion processes form urine, and capillaries where diffusion and osmosis occur.