NURS 6501-Advanced Pathophysiology Quiz 1

NURS 6501-Advanced Pathophysiology Quiz 1 How are cells specialized? - ANS through the process of differentiation or maturation What are the eight specialized cellular functions? - ANS movement, conductivity, metabolic absorption, secretion, excretion, respiration, reproduction, and communication What are the three general components of an eukaryotic cell? - ANS the plasma membrane, the cytoplasm, and the intracellular organelles. What causes the release of lysosomal enzemes? - ANS Cellular injury causing cellular self-digestion What is the location and function of the nucleus? - ANS the largest membrane-bound organelle and is found usually in the cell's center. The chief functions of the nucleus are cell division and control of genetic information. What is Cytoplasm? - ANS an aqueous solution (cytosol) that fills the space between the nucleus and the plasma membrane. What is the endoplasmic reticulum and what does it specialize in? - ANS a network of tubular channels (cisternae) that extend throughout the outer nuclear membrane. It specializes in the synthesis and transport of protein and lipid components of most of the organelles What is the Golgi complex and what does it do? - ANS a network of smooth membranes and vesicles located near the nucleus. The Golgi complex is responsible for processing and packaging proteins into secretory vesicles What are lysosomes and what do they do? - ANS saclike structures that originate from the Golgi complex and contain digestive enzymes. These enzymes are responsible for digesting most cellular substances to their basic form, such as amino acids, fatty acids, and carbohydrates What are peroxisomes? - ANS involved in the production and breakdown of hydrogen peroxide Importance of proteins in disease - ANS The major workhorses of the cell, if misfolded they can cause diseases What are mitochondria responsible for? - ANS . Mitochondria contain the metabolic machinery necessary for cellular energy metabolism (Makes ATP). What is the cytoskeleton? - ANS the "bone and muscle" of the cell. The internal skeleton is composed of a network of protein filaments, including microtubules and actin filaments (microfilaments). What is the plasma membrane? - ANS encloses the cell and, by controlling the movement of substances across it, exerts a powerful influence on metabolic pathways What is signal transduction? - ANS The transfer of molecular signals from the exterior to the interior of a cell. If not done apoptosis occurs What is protein regulation and what is it composed of? - ANS protein homeostasis and is defined by the proteostasis network. This network is composed of ribosomes (makers), chaperones (helpers), and protein breakdown or proteolytic systems. Malfunction of these systems is associated with disease. What do protein receptors do? - ANS on the plasma membrane, enable the cell to interact with other cells and with extracellular substances What means accomplish cell-to-cell adhesions? - ANS (1) the extracellular membrane, (2) cell adhesion molecules in the cell's plasma membrane, and (3) specialized cell junctions. What makes up the extracellular matrix and what does it do? - ANS (1) fibrous structural proteins (collagen and elastin), (2) adhesive glycoproteins, and (3) proteoglycans and hyaluronic acid. The matrix helps regulate cell growth, movement, and differentiation. How do cells communicate? - ANS (1) they form protein channels (gap junctions); (2) they display receptors that affect intracellular processes or other cells in direct physical contact; and (3) they use receptor proteins inside the target cell. How is intercellular signaling done? - ANS contact-dependent, paracrine, hormonal, neurohormonal, and neurotransmitter. What is ATP? - ANS Adenosine Triphosphate - ENERGY - is required for active transport. What is anabolism? - ANS energy-using process of metabolism What is catabolism? - ANS the energy-releasing process of metabolism What is passive transport? - ANS The movement of materials across the cell membrane without using cellular energy, water and small electrically uncharged molecules, done through osmosis What is oxidative phosphorylation? - ANS occurs in the mitochondria and is the mechanism by which the energy produced from carbohydrates, fats, and proteins is transferred to ATP. What is endocytosis and exocytosis? - ANS Endo= into the cell (engulf). Exo= out of the cell (excrete). What is active transport? - ANS requires the cell to expend energy (by means of ATP) to move larger molecules and molecular complexes What is pinocytosis? - ANS the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane. (drinking) How is endocytosis done? - ANS when the substance to be transported is engulfed by a segment of the plasma membrane, forming a vesicle that moves into the cell. What is phagocytosis? - ANS the ingestion of bacteria or other material by phagocytes and amoeboid protozoans. (eating) What is receptor-mediated endocytosis? - ANS receptor-mediated endocytosis to selectively take up specific molecules or complexes of molecules that cannot diffuse or move through transport proteins What is diffusion? - ANS The movement of particles from an area of high concentration to an area of low concentration. What happens after endocytosis occurs? - ANS lysosomal enzymes process and digest material What is osmosis? - ANS diffusion of water across a selectively permeable membrane What is filtration? - ANS the measurement of water and solutes through a membrane because of a greater pushing pressure. What is hydrostatic pressure? - ANS the mechanical force of water pushing against cellular membranes. What is oncotic pressure? - ANS Osmotic pressure exerted by colloids in solution. What is osmotic pressure? - ANS The amount of hydrostatic pressure required to oppose the osmotic movement of water What is the resting membrane potential? - ANS Difference in electrical charge across the membrane at rest What is action potential? - ANS the change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell. How does DNA replicate? - ANS DNA molecule unwinds and each strand is a template for complementary base pairing; each daughter helix contains an intact strand from the parent helix and a newly synthesized strand therefore DNA replication is semiconservative What are the four phases of the cell cycle? - ANS (1) the S phase, during which DNA synthesis takes place in the cell nucleus; (2) the G2 phase, the period between the completion of DNA synthesis and the next phase (M); (3) the M phase, which involves both nuclear (mitotic) and cytoplasmic (cytokinetic) division; and (4) the G1 phase (growth phase), after which the cycle begins again. What are the four stages of the M phase (Mitosis)? - ANS prophase, metaphase, anaphase, and telophase. What is DNA composed of? - ANS deoxyribose, a phosphate molecule, and four types of nitrogenous bases. The physical structure of DNA is a double helix What does DNA polymerase do? - ANS Joins individual nucleotides to make complementary strands and proofreads the sequence of bases and corrects errors What is transcription? - ANS The process of making RNA from DNA What is translation? - ANS the decoding of an mRNA message into a protein What are diploid somatic cells? - ANS Body Cells What are haploid gametes? - ANS sperm and egg cells What is a karyotype? - ANS A display of every pair of homologous chromosomes within a cell, organized according to size and shape How common are chromosome abnormalities? - ANS 1 in 150 live births, leading cause of mental retardation and miscarriage What is polyploidy? - ANS condition in which an organism has extra sets of chromosomes What is aneuploidy? - ANS Abnormal number of chromosomes. What is trisomy? - ANS 3 copies of a chromosome What is monosomy? - ANS missing one chromosome What are alleles? - ANS different versions of the same gene Compare monosomies and trisomes - ANS monosomies cause more severe physical defects than do trisomies, illustrating the principle that the loss of chromosome material has more severe consequences than the duplication of chromosome material. What are the four abnormalities of chromosome structures? - ANS deletions, duplications, inversions, and translocations. What is a locus? - ANS the precise location of a gene on a chromosome What is genomic imprinting? - ANS The silencing of a gene that is 'stamped' with an imprint during gamete production. What is epigenetics? - ANS the study of how the environment affects which genes are expressed Recurrence risk for autosomal dominant diseases - ANS 50% Recurrence risk for autosomal recessive diseases - ANS 25% What is consanguinity? - ANS marriage between blood relatives What gene determines sex? - ANS SRY gene, typically on the Y chromosome. If a Y chromosome lacks SRY gene an XY female can be produced, also if an X chromosome has an SRY gene an XX male may be produced What is a sex-influenced trait? - ANS sex influenced inheritance are genetic trends based on sex -i.e. gene that expresses for baldness in men does not for women Why would X-linked recessive genes be seen more in males? - ANS because males need only one copy of the gene to express the disease Why are skipped generation diseases seen in X-linked diseases? - ANS Biologic fathers cannot pass X-linked genes to their sons and the gene can be transmitted through carrier females What is a sex limited characteristic? - ANS one that occurs only in one sex What are polygenic traits? - ANS traits that are controlled by two or more genes Prediction of disease - ANS A marker locus, when closely linked to a disease-gene locus, can be used to predict whether an individual will develop a genetic disease. What are multifactorial traits? - ANS traits that depend on multiple genes combined with environmental influences What is cellular adaptation? - ANS a reversible, structural, or functional response both to normal or physiologic conditions and to adverse or pathologic conditions What is the threshold of liability? - ANS In many multifactorial traits, once the threshold of liability has been crossed, the disease may be expressed. What is atrophy? - ANS decrease in cell size What are the most commonly seen adaptive cell changes? - ANS atrophy, hypertrophy, hyperplasia, and metaplasia. What is hypertrophy? - ANS increase in cell size What mechanisms cause atrophy? - ANS include decreased protein synthesis, increased protein catabolism, or both What is hyperplasia? - ANS increase in number of cells caused by increased rate of cellular division What happens with hypertrophy? - ANS The amounts of protein in the plasma membrane, ER, microfilaments, and mitochondria increase What is metaplasia? - ANS a change in stress on an organ that leads to a change in cell type Most commonly involves a change of one type of surface epithelium to another *metaplastic cells are better able to handle the new stress metaplasia occurs via reprogramming of stem cells which then produce the new cell type What are free radicals? - ANS unstable oxygen-containing molecules that can damage the cells of the body and possibly contribute to the increased risk of chronic diseases What is dysplasia? - ANS an abnormal change in the size, shape, and organization of mature tissue cells. It is considered atypical rather than a true adaptational change. What can cause cell injury? - ANS lack of oxygen (hypoxia), free radicals, caustic or toxic chemicals, infectious agents, inflammatory and immune responses, genetic factors, insufficient nutrients, or physical and mechanical trauma from many causes What are the four biochemical themes associated with cell injury? - ANS (1) ATP depletion, resulting in mitochondrial damage; (2) accumulation of oxygen and oxygen-derived free radicals, causing membrane damage; (3) protein folding defects; and (4) increased intracellular calcium concentration and loss of calcium steady state. What is the sequence of events in cell death? - ANS decreased ATP production, failure of active transport mechanisms (the sodium-potassium pump), cellular swelling, detachment of ribosomes from the ER, cessation of protein synthesis, mitochondrial swelling as a result of calcium accumulation, vacuolation, leakage of digestive enzymes from lysosomes, autodigestion of intracellular structures, lysis of the plasma membrane, and death. What happens first in a hypoxic injury? - ANS the cessation of blood flow into vessels that supply the cell with oxygen and nutrients (ischemia) What is oncosis? - ANS accumulation of water causing cellular death What can cause a reperfusion injury? - ANS restoration of oxygen by oxidative stress, increased intracellular calcium concentration, inflammation, and complement activation. How can deprivation of essential nutrients (proteins, carbohydrates, lipids, and vitamins) lead to cell injury? - ANS by altering cellular structure and function, particularly of transport mechanisms, chromosomes, the nucleus, and DNA What are the two categories of intracellular accumulations? - ANS (1) normal cellular substances, such as water, proteins, lipids, and carbohydrate excesses; and (2) abnormal substances, either endogenous (e.g., from abnormal metabolism) or exogenous (e.g., a virus). What mechanisms cause accumulations? - ANS (1) An endogenous substance is produced in excess or at an increased rate; (2) an abnormal substance, often the result of a mutated gene, accumulates; (3) an endogenous substance is not effectively catabolized; and (4) a harmful exogenous substance accumulates because of inhalation, ingestion, or infection. What causes cellular swelling? - ANS the failure of transport mechanisms and is a sign of many types of cellular injury What is dystrophic calcification? - ANS hallmark of CELLULAR INJURY and occurs in all types of cell NECROSIS always in the setting of NORMAL CALCIUM LEVELS, and results in PSAMMOMA BODIES What does a disturbance in urate metabolism cause? - ANS hyperuricemia and deposition of sodium urate crystals in tissue—leading to a painful disorder called gout What are the systemic manifestations of cellular injury? - ANS fever, leukocytosis, increased heart rate, pain, and serum elevations of enzymes in the plasma What is necrosis? - ANS rapid loss of the plasma membrane structure, organelle swelling, mitochondrial dysfunction, and the lack of features of apoptosis What is apoptosis? - ANS regulated or programmed cell death and is characterized by "dropping off" of cellular fragments, called apoptotic bodies What is necroptosis? - ANS programmed necrosis What are the four types of necrosis? - ANS coagulative, liquefactive, caseous, and fatty What is endoplasmic reticulum stress? - ANS Excessive accumulation of misfolded proteins in the ER What is dysregulated apoptosis? - ANS excessive or insufficient apoptosis What are some important factors in aging? - ANS increased damage to the cell, reduced capacity to divide, reduced ability to repair damaged DNA, and increased likelihood of defective protein balance or homeostasis. What is sarcopenia? - ANS loss of muscle mass and strength What is cachexia? - ANS weakness and wasting of the body due to severe chronic illness What is somatic death? - ANS death of the entire organism What is osteogenesis imperfecta? - ANS caused by pathogenic variants (formerly termed "mutations") in collagen genes Cause of genetic disease? - ANS a change in the sequence or cellular content of DNA that ultimately deranges gene expression, deletion of a group of genes or an abnormal number of chromosomes Most genetic disorders affect all cells why? - ANS it is inherited from a mutant egg or sperm When a genetic disorder does not affect all cells what is it? - ANS a mosaic because it occurred during gestation What us an alleles? - ANS slight differences seen in a genes DNA sequence across a population What is a variant and what modifiers are used? - ANS term to define a change in DNA sequence from the population norm and is used with the following modifiers: "pathogenic," "likely pathogenic," "uncertain significance," "likely benign," and "benign." What is a single nucleotide variant? - ANS a single base pair change has occurred What is a phenotype? - ANS any characteristic that can be measured, with the type of measurement depending on the characteristic What are molecular biologic phenotypes? - ANS can be detected only with a laboratory test What is penetrance? - ANS the percentage of individuals having a particular genotype that express the expected phenotype What is fitness? - ANS how well an organism can survive and reproduce in its environment What is variable expressivity? - ANS The same altered gene giving rise to a spectrum of different phenotypes What is a neutral effect on gene activity? - ANS no effect What is an amorphic variant effect on gene activity? - ANS Complete loss of function What is a hypomorphic variant effect on gene activity? - ANS Partial loss of function What is a hypermorphic variant effect on gene activity? - ANS gain of function What is a neomorphic variant effect on gene activity? - ANS acquires a new property What is hemizygosity? - ANS a recessive inheritance that emerges in a male due to only having one X chromosome What is type 1 osteogenesis imperfecta? - ANS mild-Short stature, postnatal fractures, little or no deformity, blue scleras, premature hearing loss What is type II osteogenesis imperfecta? - ANS perinatal lethal-severe prenatal fractures, abnormal bone formation, severe deformities, blue sceleras, connective tissue fragility What is type III osteogensis imperfecta? - ANS progressive deforming- prenatal fractures, deformities present at birth, very short stature, usually nonambulatory, blue scleras, hearing loss What is type IV osteogenesis imperfecta? - ANS Deforming with normal scleras- postnatal fractures, mild to moderate deformities, premature hearing loss, normal or grey scleras, dental abnormalities What does osteogenesis imperfecta impact? - ANS type I collagen found in the dermis, connective tissue in organs, vascular and gastrointestinal adventitia, and is the only collagen in bone What is phyenylketonuria? - ANS elevated levels of urinary phenylpyruvate and phenylacetate, which occur when circulating phenylalanine levels, normally between 0.06 and 0.1 mmol/L, rise above 1.2 mmol/L What is the most common cause of hyperphenylalaninemia? - ANS deficiency of the enzyme phenylalanine hydroxylase, which catalyzes the conversion of phenylalanine to tyrosine What can result from untreated hyperphenylalaninemia? - ANS Post-natal growth restriction, moderate-to-severe intellectual disability, recurrent seizures, hypopigmentation, and eczematous skin rashes What can happen if hyperphenylalaninemia treatment is stopped too early in childhood or adolescence? - ANS neurocognitive deficits and psychiatric problems that can develop, including deficits in executive functioning and anxiety, depression, and phobias. How does Fragile X present? - ANS small joint hyperextensibility, mild hypotonia, and a family history of intellectual disability in maternally related males