What is the term for serum and lymph passing through vessel walls into tissue?

The term that refers to the process of serum and lymph passing through vessel walls into tissue is edema. Edema occurs when there is an accumulation of fluid in the interstitial spaces of the body due to various factors, such as increased hydrostatic pressure or decreased osmotic pressure within the blood vessels. This condition can lead to swelling in the affected areas, making it a significant topic in the study of various skin and tissue reactions, particularly in the context of treatments like electrolysis and laser therapy.

In contrast, the other terms relate to different processes. Inflammation is the body's response to injury or infection, characterized by redness, heat, swelling, and pain, but it is not specifically about fluid movement through vessel walls. Necrosis refers to the death of cells or tissue due to injury or disease, which is also different from the movement of serum and lymph. Hyperemia describes an increase in blood flow to specific tissues, which can also contribute to swelling but does not directly refer to the passage of serum and lymph through vessel walls. Therefore, edema specifically encapsulates the fluid dynamics described in the question.