PAS 534 Cell Physiology & Inflammation Exam | Questions with 100% Correct Answers

PAS 534 Cell Physiology & Inflammation Exam | Questions with 100% Correct Answers What is a decrease in cell size? atrophy Cell size is related to _____________ work load Atrophy is _________ workload decreased What are the causes of atrophy? - disuse - denervation - loss of endocrine stimulation - inadequate nutrition - ischemia What type of atrophy is seen in bedridden patients? Disuse What type of atrophy is loss of nerve control? Denervation What type of atrophy is seen with a loss of estrogen or testosterone? loss of endocrine stimulation What type of atrophy causes a decrease in cell energy demand? inadequate nutrition What type of atrophy causes a decrease in blood flow? Ischemia What is the mechanism of atrophy? ubiquitin-proteasome pathway Atrophy causes a _______ in metabolic activity decrease What does the ubiquitin-proteasome pathway do? tags proteins for cellular death What is increase in cell size? hypertrophy Hypertrophy is _________ workload increased Hypertrophic cells _______ undergo mitosis cannot Hyperplasic cells _______ undergo mitosis can What are the types of hypertrophy? - physical - pathologic What are the types of pathologic hypertrophy? - adaptive - compensatory What type of hypertrophy is an increase in workload not caused by disease? normal Physical labor is an example of _________ hypertrophy normal What type of hypertrophy is caused by a pathologic condition? adaptive Bladder wall thickening due to an obstruction is _________ hypertrophy adaptive What type of hypertrophy results in enlargement of remaining organ/tissue following removal or inactivity of a section? compensatory During renal failure, remaining nephrons undergo _______ hypertophy compensatory Pathologic hypertrophy is _________ at first, but eventually ___________ & may impair function beneficial; detrimental What is increase in cell number in response to stimulus? hyperplasia What is the mechanism of hyperplasia? stimulation by growth factors or activation of genes regulating cell proliferation What causes hyperplasia to stop? stimulus removal What are the types of physiologic hyperplasia? - hormonal - comphensatory What type of hyperplasia results from non-injurious stressors? physiologic What type of hyperplasia results from excessive stimulation of hormones or effects of growth factors? pathologic What type of physiologic hyperplasia is breast & uterine enlargement during pregnancy? hormonal What type of physiologic hyperplasia causes a physiologic increase in hormones and stimulation? hormonal What type of physiologic hyperplasia results from damage or resection? compensatory What type of physiologic hyperplasia is liver regeneration after partial removal? compensatory What type of hyperplasia is due to excessive stimulation of hormones or effects of growth factors? pathologic Prolonged exposure to estrogen causes: endometrial hyperplasia Endometrial hyperplasia is an example of _____________ hyperplasia pathologic What is a reversible change where one cell type is replaced by another cell type? Metaplasia In metaplasia, conversion of cell types does not overstep boundaries of the primary groups of tissues True In metaplasia, conversion of cell types overstep boundaries of the primary groups of tissues False What occurs in response to chronic irritation & inflammation? Metaplasia What is the mechanism of metaplasia? reprogramming of undifferentiated stem cells present in tissue undergoing the metaplastic changes Barrett's Esophagus is an example of metaplasia Chronic GERD causes Barrett's Esophagus In a patient with Barrett's Esophagus, ___________ epithelium convert into __________ epithelium squamous; columnar The columnar cells in Barrett's Esophagus resemble cells of the Intestine What is a patient with Barrett's Esophagus at high risk for? esophageal cancer What is deranged cell growth resulting in cells of varying size, shape, and appearance? Dysplasia What characterizes dysplasia? disordered pattern of growth What is associated with chronic irritation or inflammation? Dysplasia Dysplasia is potentially reversible True What allows for dysplasia to be reversed? removal of inciting change or irritant Where is dysplasia commonly seen? metaplastic squamous epithelium of the respiratory tract and uterine cervix What is a strongly implicated as a precursor to cancer? Dysplasia Dysplasia ________ occur in the absence of metaplasia can What occurs when cells are unable to adapt or adaptive responses are exceeded? cellular injury __________ injury always leads to cell death irreversible What is reversibility dependent on? - severity of insult - vascular supply - nutritional status - regenerative capacity What are the types of injury from physical agents? - mechanical force - temperature extremes - electrical injuries Tissue trauma and fractured bones are examples of what type of injury from physical agents? mechanical forces Low-intensity heat exposure leads to: - vascular injury - accelerated cell metabolism - inactivation of enzymes - disruption of cell membrane High-intensity heat exposure leads to: - coagulation - protein denaturation Cold exposure leads to: - vasoconstriction - increase in blood viscosity Exposure to freezing temperatures leads to: - ice crystal formation - vasoconstriction What type of injury often impacts cardiac/neural impulses? electrical impulses What is the most common cause of radiation injury? localized irradiation used in cancer treatment What are common causes of chemical injury? - pesticides - insecticides - CO - tobacco - heavy metals What are the common results of chemical injury? - membrane disruption - blocking of enzymatic pathways - protein coagulaiton - osmotic/iconic cell balance disruption What can cause cellular injury? both nutritional excess and deficiency What causes atherosclerosis? obesity or diets high in saturated fat What occurs with vitamin D deficiency? rockets (peds) What occurs with vitamin B12 deficiency? paresthesias from demyelination What occurs with vitamin C deficiency? Scurvy What populations are at risk for scurvy? elderly with poor nutrition What is intracellular accumulation? buildup of substances that cells cannot immediately use or eliminate What are the three categories of intracellular accumulations? - normal body substances - abnormal endogenous products - exogenous products When does intracellular accumulation occur? substance is produced at rate that exceeds its ability to metabolize or remove it What can disrupt metabolism of selected substances? genetic disorders In Tay Sachs, there is a deficiency of: hexosaminidase A What are the mechanisms of cellular injury? - decrease in ATP - membrane damage - increase in intracellular Ca2+ - reactive oxygen species What are free radicals? highly unstable reactive oxygen species with single unpaired electron in outer orbit ROS are energy Robbers What is a highly reactive byproduct of many normal cell reactions? free radicals What is the most reactive free radical? hydroxyl What compounds defend against free radicals? Antioxidants What causes oxidative stress? accumulation of ROS ___________ production of free radicals OR ___________ breakdown of ROS can cause oxidative stress increased; decreased What are the consequences of oxidative stress? - membrane damage - DNA damage & fragmentation - oxidative modification of proteins How does oxidative stress cause membrane damage? lipid peroxidation What is lipid peroxidation? ROS attack unsaturated fatty acids in membrane leading to oxidative stress Why is Ca2+ homeostasis important? functions in the release of intracellular enzymes Intracellular Ca2+ is normally _________ low Cellular injury occurs when intracellular Ca2+ is abnormally ________ high How does increased release of Ca2+ affect ATP? channels open in mitochondria causing ATP depletion Ca2+ activates ________ causing cellular injury Enzymes Ca2+ activation of phospholipases cause: membrane damage Ca2+ activation of proteases cause: membrane & cytoskeletal protein degradation Ca2+ activation of endonucleases cause: DNA & chromatin fragmentation Ca2+ activation of ATPases cause: ATP depletion What is hypoxic cell injury? O2 deprivation that impairs metabolism and ATP production What causes hypoxic cell injury? decrease in O2 concentration What are examples of O2 decrease? - hypoxic environments - respiratory distress - ischemia - anemia - edema - inability of cells to use O2 What is the result of cellular hypoxia? anaerobic metabolism Why is anaerobic metabolism problematic? produces lactic acid leading to decrease in pH which impairs enzyme function What cells are at the greatest risk for hypoxic cell injury? heart, brain, kidneys