A wheal is defined as what type of skin feature?

A wheal is characterized as an area of edema on the skin and is typically associated with allergic reactions or insect bites. It appears as a raised, red or pale swelling, often with a well-defined edge. This edematous feature results from a localized accumulation of fluid within the dermis, and it can be seen in various skin conditions, including urticaria (hives).

The other options describe different skin features that do not accurately define a wheal. A flat red area covered with small bumps refers more to a rash or papular eruption rather than localized swelling. A small collection of pus under the skin describes a pustule, usually related to infections or inflammatory conditions. Lastly, a cut in the skin pertains to a laceration or abrasion, distinct from the fluid-filled characteristic of a wheal. Understanding these distinctions helps in accurately identifying and documenting skin conditions effectively.