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In the alveoli, oxygen from the air is absorbed into the blood. Carbon dioxide, a waste product of metabolism, travels from the blood to the alveoli, where it can be exhaled. Between the alveoli is a thin layer of cells called the interstitium, which contains blood vessels and cells that help support the alveoli.
The epithelium is called Bowman's capsule. That part of the epithelium covering the capillaries is called the visceral epithelium. The part forming the capsule is called parietal epithelium. The filtration membrane is formed from the endothelial cells of the capillaries, basement membrane, and visceral epithelium.idney. Kidney Glomerulus. If you hold the section of the kidney up to the light, you can distinguish the CORTEX from the MEDULLA. In the Masson stained section, note the blue-stained CAPSULE covering the surface. View the same regions with the low magnification of the microscope.