MARYVILLE PATHO 611 EXAM 1; WUNDERLICH -

Describe the characteristics of apoptosis. - ANSWER A programmed cell death that is regulated or programmed. Necrosis: characterized by rapid loss of the plasma membrane structure, organelle swelling, mitochondrial dysfunction. Hypoxia is the #1 major cause of cellular injury leading to necrosis especially to the kidneys and heart. (Myocardial infarction) Page 52: What's new: Current research supports that after muscle heart injury that stem cells exist in the heart and differentiate into various cardiac cell lineages and is profoundly changing the understanding of myocardial biology!! Cellular adaptation: Atrophy - ANSWER Physiologic: thymus gland atrophy (childhood) Cellular adaptation: Hypertrophy - ANSWER Increase in size of cell Another cellular adaptation that can actually be beneficial is hypertrophy of myocardial cells such as an endurance training-this is referred to as physiologic hypertrophy. Versus pathologic hypertrophy that occurs secondary to HTN. Cellular adaptation: Hyperplasia - ANSWER Increase in number of cells Compensatory: removal of 70% off liver-can regenerate in about 2 weeks. Pathologic: endometrial hyperplasia Cellular adaptation: Metaplasia - ANSWER Replacement of cells Normal columnar ciliated epithelial cells of the bronchial lining have been replaced by stratified squamous epithelial cells. Can be reversed if irritant is stopped. Cellular metabolism: During ischemia, what effect does the loss of the adenosine triphosphate (ATP) level have on cells? - ANSWER ATP = energy BUT needs oxygen - aerobic metabolism A reduction in ATP levels causes the plasma membrane's sodium-phosphate (Na+, K+) pump and sodium-calcium exchange to fail, which leads to an intracellular accumulation of sodium and calcium and diffusion of potassium out of the cell. (The Na+, K+ pump is discussed in chapter one). Sodium and water then can enter the cell freely, and cellular swelling results. Anaerobic metabolism (glycolysis) - ANSWER Results when oxygen reserves are depleted.