NR-283 Pathophysiology - Set 2 - Part 1

Correct Answer: Grade rates cell appearance and stage rates spread

Grade comes from the microscope and reports how far the cells have drifted from normal appearance. Stage comes from anatomy, combining tumor extent, nodal involvement, and distant deposits, and it usually drives treatment. Option a is incorrect because the two definitions have been swapped. Anatomic extent is never judged by nuclear appearance, and a pathologist cannot see nodal or distant disease in a single tissue slide. Option b is incorrect because tumor size belongs to the T category within staging, not to grade at all. Symptoms play no formal part in either system, since both rest on measurable tissue findings. Option d is incorrect because prognosis and therapy are consequences drawn from grade and stage rather than definitions of them. Both systems describe the tumor itself, and the clinician then applies that description.

Correct Answer: X linked deficiency of clotting factor eight

Hemophilia A is an X linked recessive lack of factor eight, so it strikes boys. Platelets work normally, letting the first plug form, but without factor eight the clot is never stabilized and bleeding restarts. Option b is incorrect because that disorder strikes both sexes and produces mucosal bleeding such as nosebleeds and heavy periods. Joint hemorrhage is rare in it, and this boy's hallmark finding is exactly that. Option c is incorrect because destroying platelets would push the count below normal and paint the skin with petechiae. The count here is normal and petechiae are absent, which points away from primary hemostasis. Option d is incorrect because losing vitamin K stretches the prothrombin time first, since factor seven has the shortest life. That value is normal here, and a child with lifelong joint bleeds is not simply undernourished.

Correct Answer: Disseminated intravascular coagulation triggered by overwhelming sepsis

Massive tissue factor release keeps the cascade firing, so microclots plug small vessels and starve fingers and kidneys. Platelets and factors are used up in the process, and bleeding then cannot be stopped. Option a is incorrect because that immune disorder lowers platelets alone and leaves fibrinogen, prothrombin time, and D dimer untouched. It also never produces the digital ischemia and organ failure described here. Option b is incorrect because the clotting studies separate the two. In that microangiopathy the prothrombin time and fibrinogen stay normal, since platelets and von Willebrand multimers drive it rather than the cascade. Option d is incorrect because that reaction requires heparin exposure and shows clotting without bleeding, with fibrinogen preserved. No heparin is mentioned, and widespread oozing points away from it toward factor consumption.

Correct Answer: A fragment traveled to the pulmonary arteries

A piece of the leg thrombus can break loose, ride the veins through the right heart, and wedge in the pulmonary circulation. Sudden dyspnea with pleuritic pain and dread is the classic result. Option b is incorrect because a clot growing upward worsens the leg swelling and tenderness. It cannot by itself produce sudden breathlessness, since the obstruction stays inside the venous drainage of the limb. Option c is incorrect because coronary plaque rupture builds a platelet rich arterial clot, and its pain is crushing and substernal rather than sharp with each breath. A venous thrombus cannot reach the coronary arteries. Option d is incorrect because bleeding into soft tissue shows as bruising, falling hemoglobin, and hypotension over hours. Nothing about that course matches the abrupt hypoxic distress that appeared in seconds here.

Correct Answer: Acidic urine with a rising serum bicarbonate

Retained carbon dioxide makes the blood acidic, so tubular cells dump hydrogen ions into the filtrate and hold on to bicarbonate. Urine turns acidic while serum bicarbonate climbs, restoring the ratio that sets pH. Option a is incorrect because both halves run backward here. Excreting base into an alkaline urine while serum bicarbonate drops is the answer to an alkalosis, and it would deepen this client's acidosis. Option b is incorrect because the urine cannot turn alkaline while the kidney is busy shedding hydrogen ions. A rising bicarbonate is right, but it arrives only through acid loaded urine, so the pairing contradicts itself. Option d is incorrect because acid urine fits the compensation, yet serum bicarbonate must rise rather than fall for the buffer ratio to be repaired. A dropping value would push pH further down.

Correct Answer: Detecting recurrence by tracking the trend

Markers earn their keep in surveillance rather than in diagnosis. A level that falls after surgery and later climbs suggests returning disease well before symptoms appear, which prompts imaging and further evaluation. Option a is incorrect because tissue type comes from the pathologist examining biopsy material. No blood test identifies the cell of origin, which is why tissue remains the definitive step in diagnosis. Option b is incorrect because direct visualization finds lesions that no serum value reveals. Surveillance after colon resection combines marker trends with scheduled endoscopy and imaging, since each catches problems the other misses. Option c is incorrect because benign conditions raise these values and some cancers never produce them, so population screening would generate false alarms and false reassurance in roughly equal measure.

Correct Answer: Acidosis and insulin shift potassium across cell membranes

Hydrogen ions move into cells during acidosis and potassium moves out, so serum values look deceptively normal while total body stores are depleted. Insulin then drives potassium back inward and the level crashes. Option b is incorrect because aldosterone promotes potassium excretion rather than retention, trading it for reabsorbed sodium in the distal tubule. High aldosterone lowers serum potassium, which is the reverse of what is described. Option c is incorrect because osmotic diuresis flushes potassium out through the urine and empties body stores. It subtracts potassium instead of adding it, so it cannot account for a value near the ceiling. Option d is incorrect because ketoacids do not chemically capture potassium and hand it back later. They lower pH, and it is the resulting hydrogen ion exchange across the membrane that moves the electrolyte.

Correct Answer: The extent of regional lymph node involvement

N reports how many regional nodes contain tumor and where they sit, with higher numbers meaning more involvement. Cancer found in a distant node group counts as distant spread instead, not as a nodal category. Option a is incorrect because tumor multiplicity is folded into the T category for most cancers, not given a letter of its own. Counting separate masses never determines the nodal designation. Option b is incorrect because size and local extension belong to T, the first letter. Higher T numbers mean a larger mass or deeper growth into neighboring tissue, which is a separate question from node status. Option d is incorrect because distant deposits are recorded under M. That letter carries enormous weight, since any distant spread places the disease at stage four regardless of how small the primary is.

Correct Answer: Promotion is reversible when the stimulus stops

Promotion depends on continued dose and duration of the stimulus, so removing tobacco takes away the repeated push toward division. Initiated cells remain, but the drive that expands them into a tumor is withdrawn. Option b is incorrect because initiation is a permanent DNA change stamped into the cell line. Quitting cannot erase it, which is why lung cancer still appears years after the last cigarette. Option c is incorrect because progression involves accumulated mutations and genomic instability that carry the clone forward on their own. By that stage the tumor no longer needs the original carcinogen. Option d is incorrect because repair enzymes work on fresh lesions, not on mutations already fixed by a completed round of replication. Once the sequence is copied wrongly, the daughter cells inherit the error.

Correct Answer: Every cell already carries the first hit

Tumor suppressor genes behave recessively in the cell, so both copies must fail. A germline defect supplies one hit everywhere in the body, leaving a single chance event to complete the process in any cell. Option a is incorrect because that rule applies to oncogenes, the stuck accelerators, where one altered copy drives proliferation. The gene described here is a brake, and brakes must fail on both sides. Option b is incorrect because a germline mutation does not raise the mutation rate of anything. It simply places the starting point closer to malignancy, since the damage is present from conception onward. Option c is incorrect because dominance at the cellular level belongs to oncogenes. A single working suppressor copy still restrains division, which is exactly why a second inactivating event is required.

Correct Answer: Each cell type expresses a different gene set

Every somatic cell holds the identical chromosomes and genes. What separates a hepatocyte from a neuron is which genes are switched on, since gene expression rather than gene content dictates cell function. Option b is incorrect because every somatic cell descends by mitosis from one zygote and therefore holds the same maternal and paternal contribution. Parental origin does not vary from one tissue to the next. Option c is incorrect because the DNA sequence is identical throughout the body, which is exactly why a cheek swab can identify a person from any tissue sample. Sequence differences are not what distinguish tissues. Option d is incorrect because differentiation silences unused genes rather than deleting them. A liver cell still carries the neuronal instructions in its nucleus; those files simply stay closed while the liver programs run.

Correct Answer: Hypercalcemia from tumor and immobility bone loss

Bone destruction by tumor plus prolonged immobility releases calcium into the blood. High calcium depresses neuromuscular activity and blocks antidiuretic hormone at the kidney, producing lethargy, apathy, polyuria, thirst, constipation and bone pain. Option a is incorrect because a calcium deficit excites nerve membranes and produces twitching, carpopedal spasm and a positive Chvostek sign. Lethargy and stupor are the mirror image of that presentation. Option b is incorrect because dilutional low sodium from excess antidiuretic hormone gives headache, confusion and seizures with concentrated urine of small volume. This client is producing far too much urine. Option c is incorrect because low phosphate drains cellular energy stores and shows up as muscle weakness, confusion and failure to wean from a ventilator. Refeeding a malnourished client is its usual setting.

Correct Answer: Vitamin B12 shortage accounts for the first client

Both deficiencies block DNA synthesis and give identical smears, so the nervous system is the separator. Only vitamin B12 loss demyelinates the posterior columns, producing paresthesias, ataxia, and confusion, while folate loss spares the nerves. Option a is incorrect because folate lack alone cannot produce numb feet, gait trouble, or memory loss. Assigning both clients to folate would mean treating the first with folic acid while the spinal cord keeps degenerating. Option b is incorrect because iron shortage builds small pale cells, the opposite of the enlarged forms described. Hypersegmented neutrophils never accompany it either, since that finding comes from stalled nuclear maturation rather than missing heme. Option d is incorrect because it reverses the two clients. Mouth ulcers and cheilosis without any nerve involvement fit a folate problem, so the second client, not the first, is the one lacking that vitamin.

Correct Answer: Decreased plasma oncotic pressure from lost albumin

Albumin generates the pull that returns fluid to the capillary at the venous end. Losing it in the urine lowers plasma oncotic pressure, so filtered fluid stays in the interstitium and edema forms. Option a is incorrect because raised hydrostatic pressure comes from heart failure, venous obstruction or volume overload, and this client has normal pressures. The push out of the capillary was never the problem. Option c is incorrect because leaky capillaries follow burns, sepsis or anaphylaxis and let protein escape with the fluid, usually producing warm localized swelling. Nephrotic syndrome loses protein through the glomerulus instead. Option d is incorrect because blocked lymph channels trap protein locally and give firm non pitting swelling in one limb, as after axillary node dissection. This client's edema is generalized and pits.

Correct Answer: Variable expressivity of the same mutation

Expressivity describes how severely a trait shows itself in people who do express it. Both brothers express the mutation, but the range from mild spots to disfiguring tumors reflects variable expressivity. Option a is incorrect because penetrance asks whether a carrier shows any sign of the trait at all. Both brothers clearly show signs, so penetrance here is complete and cannot account for their differing severity. Option b is incorrect because anticipation means earlier onset or greater severity in each successive generation, as seen with the repeat expansions of Huntington disease. These two men belong to one generation, not consecutive ones. Option d is incorrect because mosaicism requires two genetically distinct cell lines arising after fertilization. Here the same inherited mutation sits in every cell of both brothers, and their skin findings differ for another reason.

Correct Answer: The cells cannot reach blood or lymph vessels

Blood vessels and lymphatics lie beneath the basement membrane. While that layer holds, malignant cells have no route into the circulation, so metastasis cannot occur and local removal cures the disease. Option a is incorrect because carcinoma in situ contains genuinely malignant cells with disordered nuclei and brisk mitoses. They are dangerous, and the favorable outlook rests on position rather than on any tameness of the cells. Option b is incorrect because immune surveillance failed already when this clone survived and expanded. Tumors that persist have learned to hide from cytotoxic lymphocytes, so treatment rather than immunity earns the cure here. Option c is incorrect because normal epithelium does not outpace or crowd out a neoplastic clone. Cancer cells divide without the controls that limit healthy turnover, so regeneration offers no protection against them.

Correct Answer: Iron deficiency anemia from chronic blood loss

Microcytic hypochromic cells with pica, koilonychia, glossitis, and cheilitis point to iron deficiency. Iron is needed to build hemoglobin, and monthly menstrual loss is the usual source in a woman of childbearing age. Option b is incorrect because folate shortage impairs DNA synthesis and yields large oval cells, not small pale ones. It also produces mouth ulcers and stomatitis rather than the brittle spoon nails seen here. Option c is incorrect because loss of intrinsic factor blocks vitamin B12 absorption and raises the mean corpuscular volume above normal. Paresthesias and unsteady gait would dominate that picture, and neither appears in this client. Option d is incorrect because marrow failure knocks out all three cell lines at once, so white cells and platelets would fall too. The red cells in that disorder look normal in size and color.

Correct Answer: Cytokine driven hypermetabolism with muscle breakdown

Cachexia is driven by tumor necrosis factor, interleukins, and interferon, which raise resting energy expenditure while suppressing appetite and breaking down muscle protein and fat. Feeding alone cannot restore lean tissue. Option a is incorrect because a tumor of this size cannot account for the calorie deficit by its own consumption. The wasting comes from the host response, and it continues even when intake exceeds ordinary needs. Option c is incorrect because villous atrophy belongs to celiac disease and similar mucosal disorders, and it produces steatorrhea and specific nutrient deficiencies. This client absorbs food, yet still loses lean mass. Option d is incorrect because third spaced fluid adds weight rather than removing it, and it does nothing to shrink skeletal muscle. Ascites can even mask the true extent of tissue loss on the scale.

Correct Answer: Carpal spasm when a blood pressure cuff inflates

Trousseau sign is carpopedal spasm brought out by occluding the arm with an inflated cuff. Low calcium raises nerve membrane excitability, so skeletal muscle fires spontaneously, and parathyroid injury during thyroid surgery is the classic cause. Option a is incorrect because a lost knee jerk warns of rising magnesium, and it is the reflex nurses track during a magnesium sulfate infusion. Falling calcium makes reflexes brisker, not absent. Option b is incorrect because a compressed QT interval accompanies a high calcium level, which depresses neuromuscular activity. Tetany with tingling belongs to the deficit, and the tracing there shows a stretched QT interval. Option d is incorrect because weakness climbing from the legs toward paralysis is the neuromuscular signature of a high potassium level. Nothing about neck surgery would raise potassium, and paresthesias here point to calcium.

Correct Answer: Vitamin K, which several clotting factors require for synthesis

Gut bacteria supply much of the body's vitamin K, and weeks of antibiotics wipe them out. Factors two, seven, nine, and ten then cannot be finished, and factor seven falls first, so the prothrombin time stretches. Option a is incorrect because iron shortage changes red cell size and color, leaving clotting times untouched. A client low on iron shows a falling hemoglobin, not a stretched prothrombin time. Option b is incorrect because a fall in serum calcium severe enough to derange coagulation would first cause tetany, seizures, and cardiac instability. Antibiotics do not strip calcium the way they strip intestinal flora. Option c is incorrect because that factor sits in the intrinsic limb, so its loss lengthens the activated partial thromboplastin time while the prothrombin time stays normal. Hemophilia A shows exactly that reversed pattern.