Guided Lecture Notes Chapter 2: Cellular Responses to Stress, Injury, and Aging Learning Objective 1. Cite the general purpose of changes in cell structure and function that occur as a result of normal adaptive processes. Using examples, explain how work demands or threats to survival lead to changes in cellular number, size, and/or type. Explain the factors that cause cellular adaptation to begin and end. Learning Objective 2. Describe cell changes that occur with atrophy, hypertrophy, hyperplasia, metaplasia, and dysplasia, and state general conditions under which these changes occur (refer to PowerPoint Slide 3 and Fig. 2-1). Explain how diminished work demands or harmful environmental conditions cause cells to shrink/atrophy. Explain how increased work demands result in hyperplasia or hypertrophy. Using examples, explain how chronic irritation leads to metaplasia. Describe conditions that result in cell growth that is out of control. Identify the cell change that is often linked with cancer. Learning Objective 3. Define intracellular accumulations and cite four sources. Describe the circumstances under which cells accumulate abnormal amounts of certain substances. Identify cell accumulations (lipids, glycogen, proteins, pigments) (refer to PowerPoint Slide 7). Discuss causes of reversible accumulations and how to undo them. Give examples of conditions resulting from irreversible accumulations. Explain the likely result of irreversible accumulation. Learning Objective 4. Compare the pathogenesis and effects of dystrophic and metastatic calcifications. Define dystrophic and metastatic calcification, emphasizing where each type is found. Identify conditions where dystrophic calcification occurs, and describe the pathology that is likely to result (refer to Fig. 2-3). Identify conditions where metastatic calcification occurs, and describe the pathology that is likely to result. Learning Objective 5. State and discuss two patterns of reversible cell injury. List the factors that determine the extent of cellular injury. List the factors that determine whether cell injury is reversible or irreversible. Identify causes of cellular swelling, and explain how the condition may be reversed. Identify the cause of fatty changes, and discuss in which organs these changes are most likely to occur. Compare the severity of cell injury caused by cellular swelling and fatty changes. Learning Objective 6. Describe the mechanisms whereby physical agents such as mechanical forces, extremes of temperature, and electrical forces produce cell injury. Identify common causes of injuries from physical agents. Use examples to explain how mechanical forces cause injury to the cells. Using examples, discuss the range of high temperatures that lead to cell injury. Explain how cold temperatures cause damage to the cell. List factors that determine the extent of electrical injury to the body, and discuss the effects of each factor (refer to Fig. 2-5). Learning Objective 7. Explain how the injurious effects of biologic agents differ from those produced by physical and chemical agents. Explain how biologic agents can continue to produce harmful effects. Discuss the mechanisms by which biologic agents injure the cells. Learning Objective 8. Differentiate between the effects of ionizing and nonionizing radiation in terms of their ability to cause cell injury. Explain how ionizing radiation results in the formation of free radicals (refer to Figs. 2-6 and 2-7). List the factors that affect the extent of cellular injury for both ionizing and nonionizing radiation. Compare the cell’s response to ionizing and nonionizing radiation. Describe the effects of chronic radiation. Learning Objective 9. State how nutritional imbalances contribute to cell injury. Identify nutritional excesses and nutritional deficiencies. Using examples, discuss how nutritional excesses and deficiencies may lead to cellular injury. Learning Objective 10. Describe the three major mechanisms whereby most injurious agents exert their effects. List the causes of cell injury due to ATP depletion. Describe the effects of ATP depletion, and explain how these effects cause damage to the cell. Explain how free radicals damage the cell through interruption of enzyme activity, destruction of part of the cell membrane, and damage to the DNA (refer to PowerPoint Slide 9). Describe the mechanisms in place at the cellular level that are designed to protect the cell from the damaging effects of free radicals. Learning Objective 11. Differentiate cell death associated with apoptosis and necrosis. Define apoptosis and necrosis (refer to PowerPoint Slide 17). Use examples to explain under what conditions each would occur (refer to PowerPoint Slide 19 and Fig. 2-9). Explain the process of apoptosis (refer to Fig. 2-8). Discuss the characteristics of necrosis (refer to PowerPoint Slide 20). Learning Objective 12. Compare dry, wet, and gas gangrene in regard to pathophysiology and physical outcomes. Define gangrene (refer to PowerPoint Slide 23). Identify the causes of dry, wet, and gas gangrene (refer to PowerPoint Slide 23). Describe the appearance of tissue in dry, wet, and gas gangrene (refer to PowerPoint Slide 23 and Fig. 2-10). Compare the progression of dry and wet gangrene. Identify locations where each type of gangrene is likely to be found. Identify the progression of gas gangrene. Learning Objective 13. Discuss aging in regard to the programmed change theories and the error theories. Discuss the causes of diminished cell function associated with the aging process. Compare the merits of the theory proposing that these changes are genetically programmed with the theory that changes occur due to a combination of random events and environmental damage (refer to PowerPoint Slide 26).