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United States Medical Licensing Examination (USMLE) Organ Systems: Structure, Function, and Disease Flashcards
51 question-and-answer cards covering Organ Systems: Structure, Function, and Disease as it is examined in United States Medical Licensing Examination (USMLE). 24 of them are printed below, taken from across the deck — no signup, no paywall on the preview.
24 sample cards from the Organ Systems: Structure, Function, and Disease deck
Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.
Trace the segments of the nephron in order from glomerulus to collecting duct.
Bowman's capsule → proximal convoluted tubule → loop of Henle (descending and ascending) → distal convoluted tubule → collecting duct.
What is the formula for net filtration pressure across the glomerulus?
NFP = (PGC − PBS) − (πGC − πBS); driven mainly by glomerular capillary hydrostatic pressure minus Bowman's space pressure minus capillary oncotic pressure.
Where does the loop diuretic furosemide act and on what transporter?
At the thick ascending limb of the loop of Henle, inhibiting the Na⁺-K⁺-2Cl⁻ (NKCC2) cotransporter.
Give the Henderson-Hasselbalch relationship used for blood pH.
pH = 6.1 + log([HCO₃⁻] / (0.03 × PaCO₂)). pH depends on the ratio of bicarbonate to dissolved CO₂.
How do you calculate the anion gap, and what defines a high gap?
Anion gap = Na⁺ − (Cl⁻ + HCO₃⁻); normal is 8–12 mEq/L. A high anion gap metabolic acidosis is >12 (mnemonic MUDPILES).
Distinguish nephritic from nephrotic syndrome.
Nephritic: hematuria, RBC casts, hypertension, mild proteinuria (inflammatory). Nephrotic: proteinuria >3.5 g/day, hypoalbuminemia, edema, hyperlipidemia.
What is the primary stimulus and action of aldosterone in the kidney?
Stimulated by angiotensin II and hyperkalemia; it acts on the principal cells of the collecting duct to increase Na⁺ reabsorption and K⁺/H⁺ secretion.
What cells secrete gastrin and what is its main action?
G cells of the gastric antrum secrete gastrin, which stimulates parietal cell H⁺ secretion and gastric mucosal growth.
What is the classic cause and location of duodenal versus gastric peptic ulcers?
Both linked to H. pylori; duodenal ulcers are often from increased acid and pain improves with food, while gastric ulcers worsen with food and carry malignancy risk.
Compare the hormones of the hypothalamic-pituitary-thyroid axis and their feedback.
Hypothalamic TRH stimulates pituitary TSH, which stimulates thyroid T3/T4. T3/T4 provide negative feedback on TRH and TSH.
Distinguish primary, secondary, and tertiary adrenal insufficiency by ACTH and cortisol.
Primary (Addison): low cortisol, high ACTH. Secondary: low cortisol, low ACTH (pituitary). Tertiary: low cortisol, low ACTH/CRH (hypothalamic).
What are the laboratory findings in type 1 diabetes mellitus ketoacidosis (DKA)?
Hyperglycemia, high anion gap metabolic acidosis, positive serum/urine ketones, and total body potassium depletion despite possibly normal serum K⁺.
Describe the hormonal events triggering ovulation in the menstrual cycle.
Rising estrogen from the dominant follicle exerts positive feedback on the pituitary, causing an LH surge that triggers ovulation around day 14.
What hormone maintains the corpus luteum in early pregnancy, and what produces it?
Human chorionic gonadotropin (hCG), produced by the syncytiotrophoblast, maintains the corpus luteum's progesterone output.
Which structure connects the two cerebral hemispheres, and what is the role of the internal capsule?
The corpus callosum connects the hemispheres. The internal capsule carries ascending/descending projection fibers including the corticospinal tract.
What is the resting membrane potential of a typical neuron, and which ion gradient dominates it?
About −70 mV, determined primarily by the high resting permeability to K⁺ (potassium equilibrium potential).
Differentiate an ischemic from a hemorrhagic stroke in mechanism.
Ischemic stroke results from arterial occlusion (thrombotic or embolic) causing infarction; hemorrhagic stroke results from vessel rupture and bleeding into brain tissue.
What is the classic CSF and MRI finding in multiple sclerosis?
Oligoclonal IgG bands in CSF and multiple white-matter demyelinating plaques disseminated in space and time on MRI.
Contrast the neurotransmitter and protein pathology of Parkinson versus Alzheimer disease.
Parkinson: dopamine loss in substantia nigra with Lewy bodies (α-synuclein). Alzheimer: acetylcholine deficit with β-amyloid plaques and tau neurofibrillary tangles.
What is the first-line drug for tonic-clonic (grand mal) status epilepticus, and its mechanism?
Benzodiazepines (e.g., lorazepam), which enhance GABA-A receptor chloride influx, increasing inhibitory tone to terminate seizures.
What enzyme is targeted by allopurinol, and in what joint disease is it used?
Xanthine oxidase; allopurinol reduces uric acid production for chronic management of gout.
Contrast osteoporosis and osteomalacia in terms of bone mineralization.
Osteoporosis: decreased bone mass with normal mineralization. Osteomalacia: defective mineralization of osteoid, usually from vitamin D deficiency.
Differentiate rheumatoid arthritis from osteoarthritis by joint involvement and pathology.
RA: autoimmune symmetric inflammatory arthritis of MCP/PIP with pannus and morning stiffness. OA: degenerative cartilage loss in weight-bearing/DIP joints with osteophytes.
Describe the coagulation cascade endpoint and the role of vitamin K.
Both pathways converge on factor X activation, generating thrombin that converts fibrinogen to fibrin. Vitamin K is required for γ-carboxylation of factors II, VII, IX, X, and proteins C and S.
What this deck covers
The Organ Systems: Structure, Function, and Disease deck follows the United States Medical Licensing Examination (USMLE) Organ Systems: Structure, Function, and Disease syllabus — 6 chapters and 30 topics — so questions land on material that is genuinely examinable rather than trivia around it. That works out to roughly 8.5 cards per chapter.
Answers are written to be recallable, not just readable — averaging about 138 characters, which is long enough to carry the reasoning and short enough to say out loud.
A deck like this earns its keep on the second and third pass. Read the syllabus first so you know the shape of the subject, then use the cards to find the specific facts that have not stuck.
Organ Systems: Structure, Function, and Disease flashcards FAQ
How many Organ Systems: Structure, Function, and Disease flashcards are in this United States Medical Licensing Examination (USMLE) deck?
51 cards. This page previews 24 of them, sampled evenly across the deck so you can judge the difficulty before installing anything.
Are these United States Medical Licensing Examination (USMLE) flashcards free?
Yes. The preview here is free to read with no signup, and the full 51-card deck is free inside the Examius app.
What do the Organ Systems: Structure, Function, and Disease cards cover?
They follow the United States Medical Licensing Examination (USMLE) Organ Systems: Structure, Function, and Disease syllabus — 6 chapters and 30 topics — so the questions track what is actually examinable.
How should I use these flashcards?
Read the syllabus first so you know the shape of the subject, then drill the deck. Examius schedules each card with spaced repetition, so cards you keep missing come back sooner and ones you know drift further apart.