Final answer:
Cellular accumulations in normal and injured cells are known as infiltrations, which can include proteins that have misfolded and accumulated within cells, leading to diseases such as Alzheimer's.
Step-by-step explanation:
Cellular accumulations in normal and injured cells are known as infiltrations. These accumulations may include substances that a cell has taken up from the outside environment or substances that are normally produced within the cell but have built up to excessive levels. When proteins fold incorrectly, they can lose their function and lead to accumulation within the cell. This accumulation, in the case of certain diseases like Alzheimer's or Creutzfeld-Jacob disease, involves amyloid plaques which are toxic to cells. Recognition of these accumulations has led to the exploration of new potential therapeutic strategies aimed at preventing or reducing these protein accumulations to treat diseases.