Galen Anatomy and Physiology 1 Theory Exam 2 Practice 2026 – Your All-in-One Resource to Master A&P!

Understanding how deep tissue loss goes when epithelium is shed is what this question tests. Erosion describes a shallow loss that affects only the surface epithelium and does not extend into the underlying tissue; such lesions typically heal without scarring. An ulcer, by contrast, is a deeper defect in which the epithelium has been lost and underlying tissue is exposed, creating a crater-like area that goes beyond just the surface and often heals with scar formation. A crust is just dried exudate on the surface, not tissue loss, and a scar is fibrous tissue that forms after healing, not the initial lesion. Since the description implies tissue loss that extends below the surface, the term that fits best is ulcer.