MARYVILLE NURS 611 EXAM 1 UPDATE COMPREHENSIVE QUESTIONS AND VERIFIED SOLUTIONS 2025

Nucleus - -contains the nucleolus, a small dense structure composed largely of RNA, most of the cellular DNA, and the DNA-binding proteins, the histones, that regulate its activity What 4 elements is DNA composed of? - - 1) deoxyribose phosphate molecule 2) pyrimidine bases 3) purine bases 4) hydrogen bonds (stabilize the helix through large numbers) what are Ribosomes? - -RNA-protein complexes (nucleoproteins) that are synthesized in the nucleolus and secreted into the cytoplasm through pores in the nuclear envelope called nuclear pore complexes (NPCs) What is the chief function of Ribosomes - -Chief function of ribosomes is to provide sites for cellular protein synthesis Golgi Complex - --network of flattened, smooth membranes and vesicles frequently located near the nucleus of the cell. -Proteins from the ER are processed and packaged into small membrane-bound sacs or vesicles called secretory vesicles. - refining plant and directs traffic into the cell. Lysosomes - -maintain cellular health - efficient removal of toxic cellular components -if damaged, will release and cause AUTODIGESTION -removal of useless organelles - signals cellular adaptation what do Peroxisomes contain? - -hydrogen peroxide and other oxygen reactive species Mitochondria - -- responsible for cellular respiration and energy production. -THINK ATP (energy) - ATP functions as the energy-transferring molecule. - urea and heme synthesis How does a virus get into a cell? - --through trickery! NURS 611 WGU D440 -attaches to the cell and release and enzyme to facilitate entrance to the cell -also by bacteria and parasites Diffusion - -passive process by which molecules move from an area of high concentration to an area of low concentration facilitated diffusion - --needs help to enter the cell - ex: insulin attaches to a receptor to let glucose in Active transport - --movement of a solute molecule from an area of low concentration to an area of high concentration - going against the gradient needs energy What cells in our body cannot reproduce? - -neurons, heart cells, skeletal muscle cells, red blood cells -they do not reproduce or transform, but some can be created by the body Main types of cell death? - -apoptosis and necrosis apoptosis - -a cell death that is regulated or programmed. Cellular self-destruction for elimination of unwanted cell populations Necrosis - -characterized by rapid loss of the plasma membrane structure, organelle swelling, mitochondrial dysfunction #1 major cause of cellular injury leading to necrosis - -hypoxia atrophy - -cell shrinks - decreased size Normal atrophy - -physiologic atrophy Effects of ischemia on cellular metabolism - -a reduction of ATP levels causes the plasma membrane's sodium-potassium pump and sodium-calcium exhange to fail, which leads to intracellular accumulation of sodium and calcium and diffusion of potassium out of the cell. sodium and water then can center the cell freely and cellular swelling results pathologic atrohy - -occurs as a result of of decrease in workload, use, pressure, blood supply, nutrition, and hormonal stimulation hypertophy - -increase in size of cell Hyperplasia - -increase in number of cells compensatory (liver) or pathalogical NURS 611 WGU D440 metaplasia - -replacement of cells with a different type Free Radical - -an electrically uncharged atom or group of atoms having an unpaired electron. this unpaired electron makes the molecule unstable; thus to stabilize, it gives up an electron to another molecule or steals one. Thus, it is capable of of injurious chemical bond formation with proteins, lipids, and carbohydrates - key molecules in membranes and nucleic acids. Ethanol and cellular injury - -in chronic alcoholism liver enzymes metabolize ethanol to acetaldehyde, which causes hepatic cellular dysfunction Fats/Lipids and cellular injury - -high levels of fat in blood is not detoxified by liver and fats deposits in the liver - affects liver function - non-alcoholic fatty liver disease (common in diabetics and obese individuals) Radiation and cellular injury - -main mechanism of damage to DNA (VERY BAD!!) by ionizing radiation is from the generation of reactive oxygen species from reactions with free radicals Aging and cells/tissues - -every physiologic process can be shown to function less efficiently Aneuploid cells - -do not have a mutliple of 23 chromosomes monosomy - --the presence of only one copy of a given chromosome - a form of aneuploid cell anomalies -always lethal trisomy - --three of any given chromosome -not lethal in 13, 18, or 21 Trisomy 21 - -Down Syndrome -most well known chromosomal abnormality -usual IQ between 25-70 -ASD and common facial features (low nasal bridge, protruding tongue, flat low-set ears Penetrance - -percentage of individuals with a specific genotype who also EXHIBIT the expected phenotype incomplete penetrance - -the individuals who have a disease causing allele may not exhibit the disease phenotype at all, though may be transmitted to the next generation What is Huntington's Disease? - --autosomal dominant condition -main traits = progressive dementia, increasingly uncontrolled limb movement -age dependent penetrance (40yo symptom onset) NURS 611 WGU D440 Expressivity - -extent of variation in phenotype associated with a particular genotype Cystic Fibrosis (genetics) - --autosomal recessive -most common in autosomal recessive disease in white children -affected must be homozygous for disease expressivity 2/2 recessive allele nature Breast Cancer (genetics) - --autosomal dominant -mutation to chromosome 17 (BRCA1) and 13 (BRCA2) -mutation presence = 50-80% lifetime risk Incidence rate - -number of new cases of a disease reported during a specific period (typically 1yr) divided by number of individuals in population prevalence rate - -total number of cases of a disease in the population at any given time (old and new cases) Environmental changes and epigenetics - -diet and exposure to chemicals can cause epigenetic modification Epigenetics - --bridges DNA information and function by modifying gene expression without any alteration to DNA sequence -cannot bind to RNA -reversible -twins with different disease profiles What vulnerable populations are more vulnerable to fluid imbalances? - --Infants