What is a common characteristic of psoriasis in terms of its lesions?

The characteristic lesions of psoriasis are indeed sharp, defined plaques that are often covered with silvery scales. These plaques typically arise as a result of hyperproliferation of the epidermis, leading to an accumulation of skin cells. This excessive cell turnover causes the skin to build up rapidly, forming thick patches that are distinctive in appearance. The silvery scales are composed of dead skin cells that accumulate on the surface, and the well-defined edges of these plaques set them apart from other skin conditions. This clarity in the border of the lesions is a hallmark feature of psoriasis and aids in distinguishing it from other dermatological issues.