Cells adapt to stimulus by changing... Size, number, and/or mophology True/False: Changes made by cells under stress are always reversible. False. Changes are reversible if stimulus is not too severe and not long lasting. If stimulus is severe or long lasting changes may not be reversible. Define Atrophy vs Hypertrophy Atrophy: decrease in cell size Hypertrophy: increase in cell size List some causes of atrophy Disuse, denervation, loss of endocrine stimulation, inadequate nutrition, and/or ischemia (decreased blood flow) What are some causes of cell hypertrophy? Exercise, increased workload, disease Define hyperplasia: increase in cell number Explain the two causes of hyperplasia in cells Physiologic: from hormones or increased workload Non-physiologic: exogenic androgens True/false: Hyperplasia and hypertrophy never occur together False! They often occur together and can cause an organ to become enlarged.  Hyperplasia--->Hypertrophy What are the 4 primary types of tissue? Connective Epithelial Muscle Nervous **each tissue type has subtypes Define Metaplasia: Adult cell type changes into a different adult cell type within the same primary tissue Only ___ and some _____ tissue undergo metaplasia. Epithelium and some connective tissue What commonly causes metaplasia in cells? Chronic irritation and inflammation *Might predispose to cancer What is dysplasia? deranged cell division and/or cell growth so cells vary in size, number, morphology and arrangement to one another Caused by chronic irritation and inflammation May predispose to cancer! What is intracellular accumulations? Subrstance build up within the cytoplasm, organelles, or nucleus of the cell Intracellular accumulations can come from the following three things: 1. Normal substances: lipids, proteins, carbs, melanin, bilirubin 2. Abnormal substances: excessive glycogen in cells of liver and kidney 3. Exogenic substances: environmental toxins, exogenous pigments What is Lipofuscin (in relation to intracellular accumulations) ? endogenous pigment from lysosomes "wear and tear" pigment most common in heart, nerve, and liver cells Can intracellular accumulations be reversible? Explain. Yes, if the accumulation reflects a correctable systemic disorder such as seen in jaundice Give an example of a disease that results in intracellular accumulation? Tay sachs disease Accumulates abnormal glyolipids in brain cells Pathologic calcifications from calcium salts, iron, magnesium and other mineral salts is _____? Abnormal!! adaptive response of a cell to a change Metastatic calcifications occur in (abnorma/normal) cell tissue are a result of _______. Normal cells; from hypercalcemia Give the 5 main categories of agents that cause cell damage 1. Physical agents 2. Radiation 3. Chemical agents 4. Biological agents 5. Nutritional imbalances Name the three most common mechanisms of cell injury: 1. Free radical formation: extra unpaired electrons 2. Hypoxia (lowered O2): ischemia, lowered blood flow which leads to hypoxia 3. Increased Ca++ intracellular concentration List four ways to cause hypoxia: 1. decreased hemoglobin (low iron) or abnormal hemoglobin (sickle cell anemia) so cells don't load with normal amounts of 02 2. Decreased Oxygen inspiration: high elevation 3. Edema in lungs from high BP or trauma, causes less diffusion of O2 in lung capillaries 4. Blockage/damage of vessels in local area List 2 reversible cell injuries observed under the microscope: 1. cell swelling from lack or ATP to run NA+/K+ ATPase pumps to maintain normal concentrations caused by hypoxia 2. Intracellular accumulation of fat -usually in liver, kidneys and heart _____ _____ is the first manifestation to almost all forms of injury to cells Cellular swelling seen under the microscope as small, clear vacuoles within cytoplasm What are the two types of cell death? Apoptosis and necrosis Apoptosis: programmed cell death that occurs at a certian cell age True/false: Apoptosis elicits inflammation False. fragments of dead cell are rapidly cleared before cytoplasmic contents have leaked out Give an example of apoptosis in development The development of the hand in the human embryo--webbed hands progress to non-webbed. Necrosis: death of cells in tissues of organs that are part of a living individual Which type of cell death causes inflammation?  a. apoptosis b. necrosis b. necrosis How is necrosis different from apoptosis? plasma membrane not kept intact necrosis interferes with cell replication/replacement as well as cell healing Explain liquefaction necrosis vs coagulation necrosis liquefaction necrosis damage neighboring cells so there is no remaining cellular outlines, and results in gooey, semi-fluid area. Coagulation necrosis due to acidosis, basic cell shape preserved, firm Caseous necrosis: "cheese-like", soft are seen in TB lesions What type of coagulation is characteristic of hypoxic injury? Coagulation necrosis Explain the two types of gangrene: dry vs wet Dry: form of coagulation necrosis, dry, shriveled and wrinkly, spreads slowly Wet: form of liquefaction necrosis, moist, swollen, turgid, spreads rapidly How can dry gangrene progress to wet gangrene? If bacteria invades the necrotic area the gangrene may convert to wet, which can cause systemic effects that may lead to death Explain the characteristics of gas gangrene results from necrotic tissue being infected by gas producing bacteria most commonly Clostridium perfingens Cells begin to age within the ___ decade, causing a decline in the following areas: 4th decade,  Decrease in muscle strength, cardiac reserve, vital capacity, nerve conduction time, and glomerular filtration rate What causes cell aging? Thought to be a programmed genetic change  or accumulation of DNA mutations