Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Week 1
Cellular adaptation, injury and death
| Question | Answer |
|---|---|
| Homeostasis | A dynamic, steady state within the normal range. Part of normal physiology |
| Example of homeostasis? | Electrolyte balance, temperature |
| Compensation | Making up for a defect, usually by moving some parameters outside their normal range. May be beneficial in short term, but often detrimental in long term |
| Example of compensation? | Enlarged left ventricle in response to increased blood pressure |
| What are 5 methods of cellular adaptation? | Atrophy, Hypertrophy, Metaplasia, Dysplasia |
| What is cell atrophy? | Cell shrivels due to loss of cell components |
| What causes cell atrophy? | Disuse, denervation, ischemia, nutrient starvation, interruption of endocrine signals, persistent cell injury, aging |
| How is atrophy adaptive? | Energy is directed to cells that need energy |
| The term atrophy can also apply to ____ | Organs. Decrease in organ size may involve some cell death, as well as cell atrophy. |
| What is hypertrophy? | Increase in cell size with increase in functional capacity |
| Hypertrophy is a response to | Increased demand for cell to meet increased workload |
| Examples of hypertrophy? | Increase in size of cells in heart ventricle from hypertension; Weight lifting. |
| How is hypertrophy adaptive? | Adapts to increased workload |
| What kinds of cells in the body hypertrophy? | Adipose (fat) and muscle cells |
| What is hyperplasia? | Increased division of cells (increased number of cells), in response to stressor or hormone stimulation |
| What causes hyperplasia? | Stressor or hormone stimulation |
| Examples of hyperplasia? | Increased number of RBC’s in response to high altitude. Prostate enlargement due to growth factors (hormone). Hyperplasia of the liver in response to drug use. Hyperplasia of endometrium, uterine stromal cells increase in number. |
| A callus is an example of _____ due to _____ | Hyperplasia; stress |
| How is hyperplasia adaptive? | Adapts to replace damaged cells, adds protection, allow cells to cope in different environment |
| What is metaplasia? | Replacement of one differentiated cell type that belongs there with another that is better able to withstand the injury |
| What causes metaplasia? | Injury, stress, change in environment |
| Examples of metaplasia? | GERD (Gastric Esophageal Reflux Disease), esophageal squamous epithelium are replaced by columnar epithelium that can better tolerate acidic conditions of gastric reflux |
| How is metaplasia adaptive? | Adapts to environment, stressors |
| When do metaplastic cells increase the risk of cancer? | When there are CHRONIC stressors |
| What is dysplasia? | Disorder growth of cells |
| What causes dysplasia? | Stressors |
| Dysplasia is marked by _____ cell growth that is also _____ | Abnormal, disordered |
| How is dysplasia adaptive? | Dysplasia does not appear to have positive adaptive benefit. |
| In _____ dysplasia, HPV infection if the stressor | Cervical |
| What is an example of cell injury or death due to lack of oxygen? | Hypoxia |
| What is an example of cell injury or death due to free radicals (e.g. reactive oxygen species)? | Ischemia leads to abnormal generation of reactive oxygen molecules (free radicals) |
| What effects do reactive oxygen species have on cells? | (Free radicals). They damage cell membranes, denature proteins, disrupt cell chromosomes. Also linked to initiation of inflammation cascade |
| What is an example of cell injury or death due to physical agents? | Physical/mechanical factors. Extreme temperatures, abrupt changes in atmospheric pressure, mechanical deformation, electricity, ionizing radiation. Ex. frostbite, burns, abrasions, lacerations |
| What is an example of cell injury or death due to chemical agents? | Toxic chemicals or poisons. Ex. Carbon tetrachloride, acetaminophen, heavy metals, toxic gases, corrosives, antimetabolites. Carbon monoxide, lead poisoning. |
| How do chemical agents cause cell injury? | Either directly, or when metabolized into reactive chemicals by the body |
| What is an example of cell injury or death due to biological agents? | Bacteria and viruses, as well as secondary effects of immune response. Ex. Polio virus is directly cytotopathic: can kill host cell directly without immune sys participation. |
| Cell injury by biological agent depends on... | Ability to gain access to cell and success in altering cell function |
| What is an example of cell injury or death due to radiation? | DNA or genetic damage due to radiation. Ex. acute radiation sickness w/ hematopoietic failure, destruction of epithelial layer of GI, neurologic dysfunction. |
| Radiation causes what 2 effects on cells? | Genetic damage and acute cell destruction |
| What is an example of cell injury or death due to nutritional imbalance? | Vitamin D deficiency affects bones, iron deficiency affects RBCs. Diabetes mellitis |
| Nutrition deficiencies can result from... | Poor intake, altered absorption, impaired distribution by circulatory system, inefficient cellular uptake |
| What are some common causes of cell injury due to nutritional balance? | Poverty, chronic alcoholism, acute and chronic illness, self-imposed dietary restrictions, malabsorption syndromes |
| Disuse of arm muscle can lead to _______ | Atrophy |
| Cell shrinkage due to disuse | Atrophy |
| Denervation to a group of cells | Atrophy |
| Lack of blood supply can lead to | Atrophy |
| Nutrient starvation can lead to | Atrophy |
| Interruption of endocrine signals can lead to | Atrophy |
| Persistent cell injury can lead to | Atrophy |
| Aging can lead to | Atrophy |
| What is the difference between ischemia and hypoxia? | Ischemia is the lack of blood supply, hypoxia is the lack of oxygen supply. |
| What is hypoxia? | Lack of oxygen that results in power failure within a cell, most often caused by ischemia |
| What can cause hypoxia? | Ischemia, heart failure, lung disease, RBC disorders |
| What is the most common cause of cell injury? | Ischemia. Injures cells faster than hypoxia alone |
| Why does ischemia cause faster/more injury than hypoxia alone? | Because ischemia not only disrupts oxygen supply, it also allows for metabolic wastes to accumulate and deprives the cell of nutrients for glycolysis |
| Ischemia leads to ____ deprivation, which is necessary for sodium-potassium and calcium pumps | ATP |
| Cell injury can result from what types of nutritional imbalance? | Nutrient deficiencies and excesses |
| What happens to an injured cell? (3) | 1. Intracellular accumulations (may or may not be reversible) 2. Reversible cell swelling 3. Irreversible cell injury |
| Examples of intracellular accumulations in an injured cell? | Fatty change, pathologic calcification |
| What is fatty change? | Reversible intracellular accumulation. Steatosis, accumulation of triglycerides in cell |
| What is an example of an intracellular accumulation of fat? | Fatty liver with alcohol abuse. Liver steatosis: ethanol interferes with lipid metabolism in hepatocytes. Lipids accumulate in vacuoles |
| What is pathologic calcification? | Irreversible. Calcium salts precipitate inside or outside of cells |
| What is an example of intracellular accumulation of calcium? | Hypercalcemia, calcium can precipitate in kidneys and cause kidney disease |
| Reversible cell swelling is also called _____ | Hydropic injury |
| What causes reversible cell swelling? | Failure of Na+/K+ pump. Increased Na+ inside cell pulls water into cell via osmosis |
| What can cause failure of Na+/K+ pump? | Insufficient ATP (due to ischemia, hypoxia) |
| Increased intracellular ______ can cause cell swelling | Concentration of Na+ |
| Irreversible cell injury causes cell _____ | DEATH |
| What 2 processes can cause cell death? | Necrosis and apoptosis |
| Cell death by necrosis is a _____ process | Pathological |
| How does cell death by necrosis occur after reversible swelling? | Continued swelling of organelles causes disruption of their membranes |
| What happens in cell necrosis? | Cell membrane ruptures, spilling cellular contents into interstitial fluid |
| Cell membrane rupture during necrosis causes _____ | Inflammation |
| What causes inflammation during necrosis? | Spilling of cellular contents into interstitial fluid |
| _________ enzymes inside the cell digest cell components | Lysosomal |
| What are biomarkers in relation to necrosis? | Intracellular components in the blood that can be used as markers of necrosis |
| Name one way necrosis can be detected | Biomarkers. Intracellular components in blood that can be used as markers of necrosis |
| What is an example of detectable necrosis of heart muscle? | Increased creatine kinase (CK) and/or cardiac troponin in the blood indicates myocardial damage |
| What is an example of a pancreatic necrosis marker? | Increased serum amylase indicates pancreatic damage |
| What are the terms used to describe necrotic tissue? | Coagulative, liquefactive; dry gangrene, wet gangrene |
| What is coagulative necrosis? | Area is composed of denatured proteins and is relatively solid. General tissue architecture is preserved for relatively long time (weeks) |
| Where can coagulative necrosis occur? | Heart, kidney, most other tissues |
| What is liquefactive necrosis? | Liquefied area of lysosomal enzymes and dissolved tissue may result and form an abscess or cyst |
| Where can liquefactive necrosis occur? | Brain is rich in degradative enzymes and has little supportive connective tissue |
| Liquefaction can also result from a ______ infection | Bacterial infection that triggers a localized collection of WBCs. |
| What is gangrene? | A large area of tissue that became necrotic from loss of blood supply and has been influenced by its environment to become wet/dry. |
| Gangrene is necrosis that results from _________ | Loss of blood supply |
| What is dry gangrene? | Coagulative necrosis |
| How is dry gangrene characterized? | Blackened, dry, wrinkled tissue that is separated from adjacent healthy tissue by an obvious line of demarcation. Generally only occurs in extremities. |
| What is wet gangrene? | Liquefactive necrosis |
| How is wet gangrene characterized? | Typically found in internal organs, appears cold and black, may be foul-smelling due to bacteria. May be life-threatening due to rapid spread of tissue damage and release of toxins into blood |
| What is apoptosis? | Programmed cell death, or cell suicide |
| Is apoptosis a normal or pathologic process? | Normal |
| What does apoptosis accomplish? | Normal process that has physiologic functions in removing unwanted, redundant or damaged cells |
| Certain types of ____ ______ may also trigger apoptosis. | Cell injury |
| “Abnormal” apoptosis? | Apoptosis may be triggered inappropriately in some disease processes and suppressed inappropriately by others |
| What triggers apoptosis? | Actions at cell membrane receptors or by intracellular factors |
| Apoptosis trigger _____ | CASPASES |
| What are the enzymes that, triggered by apoptosis, dismantle the cell? | Caspases. They become activated inside the cell and dismantle it in an orderly fashion. |
| What are apoptotic bodies? | Membrane-bound vesicles that package cell components |
| What are membrane-bound vesicles that package cell components in apoptosis? | Apoptotic bodies |
| Apoptotic bodes are disposed of by ______ | Phagocytic cells |
| True or false: Apoptosis triggers inflammation. | False. Cell contents are not released into the interstitial fluid, so inflammation does not occur |
| Does apoptosis trigger inflammation? Why? | No, because cell contents are not released into the interstitial fluid |
| Examples of apoptosis? | Embryonic webbing in utero, “pruning” of brain cells, neutrophils after immune response |
| Which cells undergo apoptosis? | WBCs |
| Do RBCs undergo apoptosis? | No, they are recycled |
| What is a telomere? | Cap at the end of chromosome. Shortens with each cell division |
| Cells undergo a finite number of replications. | |
| What is telomerase? | Enzyme that builds telomeres. Allows cancerous cells to keep dividing |
| What is algor mortis? | Postmortem reduction of body temperature |
| What is poikilothermia? | Body temperature equals environmental temperature after death |
| What is livor mortis? | Also called postmortem lividity. Purple discoloration of dependent areas of skin due to blood pooling |
| What is rigor mortis? | Stiff muscles after death |
| What is postmortem autolysis? | Dissolution of cells due to bacterial action after death |
| Put in order of occurrence: Rigor mortis, algor mortis, postmortem autolysis, livor mortis, poikilothermia | Algor mortis, poikilothermia, livor mortis, rigor mortis, postmortem autolysis |
Created by:
kangaloo