Which of the following is a reversible procedure

Refer ribbons 7/e p79 The two main morphologic correlates of reversible cell injury are cellular swelling and fatty change. Cellular swell- ing is the result of failure of energy-dependent ion pumps in the plasma membrane, leading to an inability to main- tain ionic and fluid homeostasis. Fatty change occurs in hypoxic injury and in various forms of toxic or metabolic injury and is manifested by the appearance of small or large lipid vacuoles in the cytoplasm. In some situations, potentially injurious insults induce specific alterations in cellular organelles, like the ER. The smooth ER is involved in the metabolism of various chemi- cals, and cells exposed to these chemicals show hypero- phy of the ER as an adaptive response that may have impoant functional consequences.