Download ADVANCED PATHOPHYSIOLOGY mODULE 1 QUESTION AND ANSWERS UPDATED 2024 and more Exams Pathophysiology in PDF only on Docsity!
Advanced Pathophysiology Module 1
Basic Cellular Functions -
- Movement
- Conductivity
- Metabolic Absorption
- Secretion
- Excretion
- Respiration
- Reproduction
- Communication Functions of Plasma Membrane -
- Structure
- Protection
- Activation of Cell
- Transport
- Cell to Cell Interaction Nucleus Function - Membrane bound structure, controls cell division and contains genetic information/material Cytoplasm - Cytoplasmic matrix that surrounds organelles Mitochondria - Primary energy maker, responsible for cellular respiration & energy production, makes ATP Smooth Endoplasmic Reticulum - An endomembrane system where lipids are synthesized, calcium levels are regulated, and toxic substances are broken down. Rough Endoplasmic Reticulum - An endomembrane system covered with ribosomes where many proteins for transport are assembled. Golgi apparatus - A system of membranes that modifies and packages proteins for export by the cell Lysosomes - originate in Golgi, 40 digestive/degradative enzymes that catalyze proteins, lipids, nucleic acids, carbs
Peroxisomes - Contain oxidative enzymes that detoxify compounds and fatty acids and breakdown substances into harmless products Cytoskeleton - A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement Vesicles - small membrane sacs that specialize in moving products into, out of, and within a cell What are the 3 phases of catabolism for the production of ATP? -
- Digestion - large molecules are broken down into smaller subunits (proteins --> amino acid; polysaccharides --> simple sugar; fats --> fatty acid and glycerol)
- Glycolysis and oxidation - small molecules are further broken down (Sugars --> pyruvate --> enters mitochondria, becomes acetyl CoA) (anaerobic and aerobic metabolism---> aerobic moves on to KC)
- Kreb's Cycle - starts with Kreb's cycle; ends with oxidative phosphorylation Oxidative phosphorylation (in the mitochondria) ---> 36 ATP are formed Whats the difference between anaerobic metabolism and aerobic metabolism? -
- Lack of oxygen (anaerobic metabolism) --> remaining pyruvate becomes lactic acid
- With oxygen (aerobic metabolism) --> pyruvate becomes acetyl CoA and goes to the Kreb's cycle what is glycolysis - the splitting of glucose to pyruvate (produces 2 ATP) What is an amphipathic molecule? - A molecule that has a hydrophilic and hydrophobic end. Example: phospholipids Vacuole - Cell organelle that stores materials such as water, salts, proteins, and carbohydrates Ribosomes - RNA protein complex that is responsible for protein synthesis (free & attached) Cell membrane (plasma membrane) - phospholipid bilayer that surrounds all cells and regulates what enters and leaves the cell Muscle Cells Function -
- Movement
- Can be striated (skeletal) or smooth (bowels, bronchi)
- Can generate forces that produce motion
- Can be smooth AND striated (diaphragm or intercostals)
hypotonic solution is one in which the concentration of solutes is greater inside the cell than outside of it Isotonic - Isotonic environment, the relative concentrations of solute and water are equal on both sides of the membrane. Osmolality - osmoles of solute per kilogram of solvent (Osm/kg) Osmolarity - osmoles of solute per liter of solution (Osm/L) Osmosis - a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane. Solute vs. Solvent - Solute : What is dissolved in a solution(salt) Solvent : What dissolves the solute(water) Diffusion - The movement of particles from an area of higher concentration to lower concentration. Filtration - Filtration is movement of water and solute molecules across the cell membrane due to hydrostatic pressure generated by the cardiovascular system. Hydrostatic Pressure - hydrostatic pressure in blood vessels is the pressure of the blood against the wall. It is the opposing force to oncotic pressure. Tonicity - solute can exert a certain amount of pressure referred to as tonicity. This pressure can affect the fluid volume and the pressure in a cell by affecting the movement of water down its concentration gradient. Passive Transport - Movement of ions and other atomic or molecular substances across cell membranes without need of energy input. Types of Passive Transport -
- Simple Diffusion
- Facilitated Diffusion
- Filtration
- Osmosis Facilitated Diffusion -
Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins. Moves with concentration gradient Active Transport - Active transport is the movement of a substance across a membrane against its concentration gradient. Requires ATP Exocytosis - a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane. equilibrium potential - When an ions concentration gradient is equal to its electrostatic gradient Endocytosis - The taking in of matter by a living cell by invagination of its membrane to form a vacuole. Action Potential - An action potential (AP) is the mode through which a neuron transports electrical signals. It is defined as a brief change in the voltage across the membrane due to the flow of certain ions into and out of the neuron. Depolarization - The process during the action potential when sodium is rushing into the cell causing the interior to become more positive. Depolarization is a change within a cell, during which the cell undergoes a shift in electric charge distribution, resulting in less negative charge inside the cell. Repolarization - Period during which potassium ions diffuse out of the neuron. Repolarization refers to the change in membrane potential that returns it to a negative value just after the depolarization phase of an action potential has changed the membrane potential to a positive value. Hyperpolarization - It inhibits action potentials by increasing the stimulus required to move the membrane potential to the action potential threshold.
- Less Excitable Hypopolorization - Smaller than normal stimulus could reach threshold potential and depolarize the cell.
- More Excitable
What is transient direct link-up signaling? - When cell to cell receptors link together temporarily to communicate Desmosomes - Desmosomes are intercellular junctions that provide strong adhesion between cells. Because they also link intracellularly to the intermediate filament cytoskeleton they form the adhesive bonds in a network that gives mechanical strength to tissues. Paracrine Cell Communication - Paracrine signaling is a form of cell signaling or cell-to-cell communication in which a cell produces a signal to induce changes in nearby cells, altering the behavior of those cells. Autocrine Cell Communication - Autocrine signaling is a form of cell signaling in which a cell secretes a hormone or chemical messenger that binds to autocrine receptors on that same cell, leading to changes in the cell. 4 Basic Types of Tissue -
- Epithelial
- Connective
- Muscle
- Neural 5 Types of Cellular Adaptation -
- Atrophy
- Hypertrophy
- Hyperplasia
- Dysplasia
- Metaplasia Atrophy -
- Shrinking in size such as skeletal muscle atrophy. Disuse atrophy, withdrawal of growth factors or hormones
- Physiologic atrophy—thymus gland atrophies in childhood Hypertrophy -
- Enlarging of cells and thus the organ usually due to increased workload
- Ex. Left ventricular hypertrophy, cells enlarge not multiply
- Physiologic hypertrophy turns into pathologic. Hyperplasia -
- Multiplication of cells (increased number of normal appearing cells in response to physiologic or excessive hormonal stimulation
- Increased rate of cell division
- After ovulation, estrogen stimulates endometrium to grow & thicken for implantation. anaplasia - lack of differentiation; cells are unorganized Dysplasia -
- Change in size, shape or organization, abnormal development of cells.
- May be reversible, may lead to malignancy
- IT IS NEVER NORMAL
- Ex. Epithelial, cervical Metaplasia -
- Reversible replacement of one mature cell by another differentiated cell type
- Bronchial columnar cells by squamous cells (recurrent injury)
- Squamous cells do not secrete mucus or have cilia thus loosing vital protective mechanism Aquaporins - Aquaporins, also called water channels, are integral membrane proteins from a larger family of major intrinsic proteins that form pores in the membrane of biological cells, mainly facilitating transport of water between cells. Net Filtration -
- Is a calculation of the forces that favor filtration vs the forces that oppose filtration Fluid distribution between the permeable capillaries of the vascular and interstitial bed is going to be the net result of oncotic pressure and hydrostatic pressure—measurements of these forces pulling and pushing against each other
- Pushing and pulling of fluid will determine if fluid moves out of capillary and into interstitial space=filtration. Or if fluid moves into the venous end of the capillary=reabsorption Examples That Cause Edema -
- Liver failure resulting in portal hypertension causing fluid to leak out of capillaries. Also decreases the production of blood proteins such as albumin, decreasing osmotic pressure in vessels.
- Hypertension leading to increased hydrostatic pressure filtering more fluid into interstitial space.
- Increase in blood vessel permeability due infection or injury or burn causing increased fluid to accumulate in interstitial space.
- Increased venous pressure and decreased reabsorption and thus increased hydrostatic pressure due to heart failure.
- Lymphatic obstruction decreasing absorption of fluid into lymphatic system.
Fever (Increases respiratory rate losing water, sweating, decreased fluid intake), Polyuria (Diabetes mellitus, Insipidus, and diuretic use), End-Stage Renal Disease (Tubal dysfunction and Free water clearance dysfunction. Hypernatremic Exam Findings - Intracellular dehydration, convulsions, pulmonary edema, hypotension, tachycardia, increased serum osmolality, increased serum sodium, decreased urine output (Unless caused by polyuria or diuretics), increased urine specific gravity. Clinical manifestations related to shrinking of the brain cells and alterations of membrane potentials Hypotonic Dehydration (Hyponatremia) - Sodium Loss is Greater than water loss. Decreases serum osmolality, shifts water from extracellular to intracellular. *Hyponatremia most commonly caused by water excess and/or retention rather than sodium loss. Causes of Hyponatremia - Addison's Disease (Adrenal insufficiency, decreased cortisol and aldosterone production), Renal tubular acidosis, Diuretics (Loop, Thiazides and Osmotic Diuretics), Cystic Fibrosis (defective Chloride Ion Transport resulting in excessive sodium loss in sweat.) Excess water intake or IV fluid intake. SIADH, Cirrhosis, CHF (Increased AVP and compensatory response). Hyponatremia Exam Findings - Decreased sodium level, decreased serum osmolality, cerebral edema, decreased urine specific gravity, headache, nausea, lethargy, confusion, coma, death. Causes of Hyperkalemia - Acute kidney failure, chronic kidney disease, addison's disease, Angiotensin II blockers, ACE inhibitors, beta blockers, dehydration, red blood cell destruction from injury or burns, Excessive Potassium supplementation, Type 1 DM, Spiranolactone. Hyperkalemia S/S - M.U.R.D.E.R. M - Muscle cramps U - Urine, oliguria, anuria R- Respiratory distress D - Decreased cardiac contractility E - ECG changes-short qt, tall P waves R - Reflexes, hyperreflexia, or areflexia (flaccid) Tingling of lips, fingers, restlessness, hypopolarization of neuromuscular membranes. Hypokalemia S/S - A SIC WALT Alkalosis Shallow respiration Irritability Confusion and drowsiness
Weakness and fatigue Arrhythmias- irregular heart rate, tachycardia, prolonged qt, depressed P wave Lethargy Thready pulse decrease intestinal mobility, nausea and vomiting, decreased neuromuscular excitability deu to hyperpolarization. Hypokalemia Causes - B.A.D. L.O.A.D. B-arters/Conns syndrome (hyperaldosteronism) A-lkalosis D-iuretics L-axative abuse O-ther causes: insulin overdose A-cute glucose load D-iarrhea Alcohol use, chronic kidney disease, DKA, Folic acid deficiency. Hypercalcemia S/S - BACK ME B-one Pain A-rrhythmias C-ardiac Arrest,Constipation K-idney stones M-uscle Weakness E-xcessive Urination Hypercalcemia Causes - 90% attributed to Hyperparathyroidism and Cancers. Other causes - Vitamin D and dietary calcium excess, hyperthyroidism, paget's disease, thiazide use. Hypophoshphatemia Causes - Intestinal malabsorption Increased renal excretion Hyperparathyroidism malnutrion, Vit D, deficiency, alcoholism, severe burns, DKA, Fanconi Syndrome, X-linked familial hypophosphatemia Hypophosphatemia S/S - Paresthesias, Muscle weakness, Muscle pain, Mental changes, Cardiomyopathy, Respiratory failure, increased serum calcium. Hyperphosphatemia Causes - Hypoparathyroidism, High Vit D, DKA, muscle damage, infections, acute and chronic renal failure, treatment with chemotherapy (releases large amounts of phosphate into serum), laxative and enema use containing phosphates.
lungs as a buffer - buffer by increasing or decreasing the respiratory rate and therefore the amount of CO available to make H2CO3 in the blood. More CO2 → lower pH, therefore increased respirations will exhale CO2 and increase the pH and vice versa.
- work faster than kidneys Protein Buffer System - Hemoglobin serves as buffer. Hemoglobin = Amino Acid which has NH3+ _C_COO-, H+ can bind to COO- if blood is acidic, or release the H+ if blood is alkalinic. NH3+ can drop a H+ if blood is alkalinic or bind a H+ if blood is acidic. Approx 250 million Hemoglobin in every RBC. Causes of Alkolosis - Hyperventilation, vomiting, increased H+ loss from diuretics, high altitudes, hyper-metabolic states such as fever. Bicarbonate Buffer System - a solution of carbonic acid and bicarbonate ions, regulated by lungs by blowing off CO2 and Kidneys by releasing Bicarbonate and/or excreting H+
- main plasma buffering system along with HgB
- works fast Ammonia Buffer System - Ammonium is generated in tubular cells through glutamine metabolism. Ammonia binds to protons and helps kidneys when maximum proton absorption by tubules are reached. Phosphate Buffer System - Buffers ICF and Urine. Consists of Dihydrogen phosphate ions and Hydrogen Phosphate ions. Dihydrogen Phosphate can release an H+ increasing acidity and Hydrogen Phosphate ions can bind H+ to increase alkalinity. (works rapidly) DNA Structure - DNA consists of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine What causes edema? -
- venous or lymphatic obstruction
- loss of plasma proteins
- increase capillary permeability
- increased vascular volume DNA Function -
Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the development and function of living things. All known cellular life and some viruses contain DNA. The main role of DNA in the cell is the long-term storage of information. What is considered the backbone of DNA - Deoxyribose - Deoxyribose is the five-carbon sugar molecule that helps form the phosphate backbone of DNA molecules. What is a codon? Anticodon? - A codon is a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule. Such as UAG, AGA, GAC. An anticodon is a series of 3 unpaired bases that is complementary to to a codon. For example the codon UAC‛s anticodon is AUG. The Codon directs ribosomes to create an amino acid. What does the rough ER produce? - proteins What does the smooth ER produce? - lipids Name examples of ligands. - Hormones, neurotransmitters, antigens and drugs Define cell to cell adhesion. - How groups of cells are held together to form tissues and organs What are the purposes of cell to cell junctions? - Cellular communication, transportation of materials between cells, increased tissue structure, to create a barrier from specific substances How is facilitated diffusion different from diffusion? - Transport proteins (specific) or channels (nonspecific) are used in facilitated diffusion; helps larger molecules move without energy Explain how the sodium potassium pump works - The pump uses ATP to move Na+ out of the cell and K+ into the cell. Against the concentration gradient equilibrium potential - the membrane potential at which chemical and electrical forces are balanced for a single ion. resting membrane potential - the electrical charge of a neuron when it is not active What is the typical value for the resting membrane potential -
- 70mV to - 85mV action potential -
hyperlipidemia DM HTN ischemic heart disease chronic inflammation oxidative stress - a condition in which the production of oxidants and free radicals exceeds the body's ability to handle them and prevent damage Coagulative necrosis - cell proteins are altered or denatured due to hypoxia caused bu severe ischemia; protein albumin change from a gelatinous, transparent state to a firm, opaque state (cooked egg white) Where does coagulative necrosis occur? - heart, kidneys and adrenal gland liquefactive necrosis - ischemic injury to neurons and brain cells. self-digestion leads to liquid which is encalsulated in cysts and abscesses. (pus accumulation) Where is liquefactive necrosis most likely to occur? - abscesses or localized bacterial infections; examples are staph, strep, and e.coli caseous necrosis - Combination of coagulative and liquefactive necrosis. Indicative of TB or fungal infection (resembles cheese) fat necrosis - caused by cellular breakdown of lipase. the necrotic tissue appears chalky and white. Where does fat necrosis occur? - adipose tissue; breast, pancreas and abdominal structures Gangrenous necrosis - severe hypoxic injury such as blockage to major artery ; basically coagulative necrosis applied to an ischemic limb dry gangrene - result of coagulative necrosis; dry, brown or black wet gangrene - develops when neutrophils invade the site, causing liquefactive necrosis; site is cold, swollen and black with foul odor gas gangrene - due to anaerobic bacterial infection; can lead to death if enzymes destroy the O2 carrying capacity of RBCs
How does chemical injury to the cell occur? - begins with biochemical interaction between toxic substance and the cells plasma membrane, causing damage (increased permeability) examples of chemical injury to the cell - lead, carbon monoxide, mercury, and street drugs How does ethanol use cause cellular injury? - alcohol is metabolized by the liver, in chronic alcoholism causes an increase in free radicals causing cellular damage Examples of unintentional and intentional cellular injuries -
- blunt & sharp force injuries
- gunshot wounds
- asphyxiation ionizing radiation - x-rays, gamma rays, alpha & beta rays, sunlight all lead to damaged DNA. cells that divide rapidly are most sensitive examples of cells that divide rapidly - fetus, germ cells, tumor cells, GI mucosa and bone cells how does hypothermic cellular injury occur? - frostbite; initial vasoconstriction with paralysis of vasomotor control leads to vasodilation --
increased membrane permeability ----> cellular swelling and increased blood viscosity = ischemic injury partial thickness burn - capillary dilation and increased loss of protein rich fluid (redness, swelling and blistering) full thickness burn - extensive loss of fluid and plasma proteins, cellular regeneration is not possible so grafting is needed define cellular accumulation - manifestations of cellular injuries; or infiltrations cellular accumulation of water - cellular swelling cellular accumulation of lipids & carbs - caused by fatty changes in the liver; carb accumulations can lead to clouding of the cornea, joint stiffness and mental retardation cellular accumulation of glycogen - occurs in diabetes; glycogen can accumulate in cells via vacuoles cellular accumulation of proteins -
pressure, increase in coronary inflammation, decrease in atherosclerosis, a limit in ischemia-reperfusion injury, and a decrease in diabetic vessel pathology. What causes respiratory acidosis? - decreased ventilation which causes an increase in CO2 = hypercapnia What causes respiratory alkalosis? - hyperventilation; excessive reduction of CO2 = hypocapnia What causes metabolic alkalosis or acidosis? - abnormal bicarb concentration What causes an increase in bicarb concentration? - (metabolic alkalosis) loss of metabolic acids; vomiting, gastric suctioning, diuretics, hyperaldosteronism, increased bicarb intake Describe the term "fatty liver" and what it indicates - Due to the abnormal accumulation of intracellular lipids in the liver, it undergoes a change in appearance. The lipids fill the cells which pushes the nucleus and other organelles aside. This gives the liver a yellow, greasy appearance.
