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USMLE Step 1 Prep

Subjects : health-sciences, usmle-step-1

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What disorder leads to IgG autoantibodies to the TSH receptor?
Graves disease
Barbiturate overdose and benzodiazepine withdrawal carry the highest mortality rates.
Acebutolol and Pindolol
Clostridium perfringens

2. What small - facultative gram - negative intracellular rod's transmission is associated with unpasteurized dairy products and undulant fever?
Ileum
'Lady between two Majors': latissimus dorsi - pectoralis major - and teres major
Brucella
GH. The largest output of GH in a 24- hour period is during stage 4 sleep.

3. What is the primary end product of pyrimidine synthesis?
Propionibacterium acnes
Obesity - DM - HTN - multiparity - early menarche - and late menopause
Middle cerebral artery
UMP

4. If the family member of a patient asked you to withhold information - would you?
There would be a Fab' region; thus - it would still be able to participate in precipitation and agglutination.
For the USMLE Step 1 the answer is no - but if the information would do more harm than good - withhold. This is very rare but it does occur.
cDNA libraries are derived from mRNA - are continuous - and contain no introns or regulatory elements.
1. Decrease concentrations of Ag levels 2. Administer IgG in high concentrations 3. Inhibit B cells with Ag bound to IgG (complexes) 4. Turn off the original T or B cell with anti - Ab

5. What type of healing occurs in a clean surgical incision?
Minimal change disease
Primary intention
Astrocytes
Cushing's ulcers

6. What vitamin is a component of the coenzyme thiamine pyrophosphate (TPP)?
Thymine (B1)
Chromosome 13
Functional residual capacity (FRC)
Anemia of chronic disease

7. Testing of a drug in a small group of volunteers without the disease is a component of which phase of clinical drug testing?
Mesonephric duct (ureteric bud)
Fanconi - like syndrome
Lipoid nephrosis
Phase 1

8. Panic attacks can be induced by __________ or carbon dioxide.
G-6- PD deficiency
Papillary carcinoma of the thyroid
hyperventilation
Theca cell

9. What is the first sign of megaloblastic anemia on a peripheral blood smear?
Hypersegmented neutrophils
Stratum spinosum
Sphingomyelin
Patent urachus

10. What statistical test compares the means of groups generated by two nominal variables by using an interval variable?
Plasmodium falciparum
Two - way ANOVA. It allows the test to check several variables at the same time.
Eosin
Hallucinations are sensory impressions (without a stimulus); illusions are misperceptions of real stimuli; and delusions are false beliefs that are not shared by the culture.

11. Are hemorrhagic cerebral infarcts more commonly associated with embolic or thrombotic occlusions?
Semicircular canal
Amphotericin B
Paradoxic emboli most commonly enter the arteries through a patent septal defect in the heart.
Embolic

12. What viral infection is associated with black vomit?
Hemostasis
Yellow fever (flavivirus)
Waldeyer's ring
Heparin - intrinsic pathway - PTT; warfarin - extrinsic pathway - PT (mnemonic: hPeT - wPiTT)

13. What causes slow writhing movements (athetosis)?
False - positive rate
Hypermyelination of the corpus striatum and the thalamus (seen in cerebral palsy)
Craniopharyngioma
PGE2

14. In a topographical arrangement of the cerebellar homunculus map - What area or lobe x Controls the axial and proximal musculature of the limbs?
Under normal resting conditions no - but they are strongly stimulated when PO2 arterial levels decrease to 50 to 60 mm Hg - resulting in increased ventilatory drive.
The vermis
Atropine with pralidoxime
Dissociative fugue. (Patients are unaware of memory loss.)

15. What type of fiber or fibers are carried in (answer motor - sensory - or both) x Dorsal rami?
O2 has a higher driving force but is only one - twenty- fourth as soluble as CO2. CO 2 has a very small partial pressure difference across the alveolar membrane (47-40 = 7 mmHg) - but it is extremely soluble and therefore diffuses readily across the
Both
The inner membrane of the mitochondria (cristae)
Surface tension - the force to collapse the lung - is greatest at the end of inspiration.

16. What bile pigment is formed by the metabolism of bilirubin by intestinal bacteria - giving stool its brown color?
Meiosis I; disjunction with centromere splitting occurs during meiosis II.
Standardized rate
CN X (Remember - the vagus nerve supplies the parasympathetic information from the tip of the pharynx to the end of the midgut and all between.)
Stercobilin

17. Name the MCC - Pneumonia in a patient with atypical bird exposure and hepatitis
Chlamydia psittaci
Acetoacetate - acetone - and Beta- hydroxybutyrate
50% - with 50% of them having the child
Type II symptoms (negative); otherwise healthy persons have them - but schizophrenics do not.

18. What Vi - encapsulated gram - negative motile anaerobic rod that produces H2S is associated with enteric fever - gastroenteritis - and septicemia?
Pyridoxine (B6)
Projective drawing. The artistic form is irrelevant - but the size - placement - erasures - and distortions are relevant.
Type II symptoms (negative); otherwise healthy persons have them - but schizophrenics do not.
Salmonella typhi

19. What is the DOC for coccidioidomycosis?
CD21; it is a complement receptor for cleaved C3
Borrelia recurrentis
Embolism
Fluconazole

20. Name four chemotactic factors for neutrophils.
HGPRT
Amiloride
No - it is used in chronic treatment of gout to decrease the uric acid pools in the body.
N- formyl - methionine LTB4 C5a IL-8

21. What three organs are necessary for the production of vitamin D3(cholecalciferol)?
enveloped
Sympathetic nervous system
Skin - liver - and kidneys
Anatomical dead space - which ends at the level of the terminal bronchioles.

22. What frontal lobe cortex is associated with organizing and planning the intellectual and emotional aspect of behavior?
Total and NREM sleep decrease considerably as we age - but REM sleep remains relatively constant (20%) up to age 80 - then begins to decline.
V wave
Both
Prefrontal cortex; it is in front of the premotor area.

23. What is the only 17- hydroxysteroid with hormonal activity?
Squamous cell carcinoma
Cortisol - a 21- carbon steroid - has a - OH group at position 17.
Hydroxyapatite
Adenovirus

24. What is the only sphingolipid that contains choline and PO4?
Intention tremor; it is a sign of cerebellar lesions. A tremor at rest (i.e. - pill rolling) is seen in basal ganglia lesions.
Sphingomyelin (lecithin also - but it is not a sphingolipid)
Succinylcholine
G-6- PD deficiency

25. If you double the infusion rate of a drug - how long will it take to reach steady state?
Intrapleural pressure decreases (becomes more negative).
TXA2
Regardless of the rate of infusion - it takes 4 to 5 half - lives to reach steady state.
Translation

26. What is the rate - limiting step in the production of steroids?
Osteosarcoma
Projective test. Most tests with a wide range of possibilities for the answers are projective.
The conversion of CHO to pregnenolone via the enzyme desmolase
Reject it

27. How long is the transit time through the large intestine?
Primary hypoparathyroidism
Extracellular
3 to 4 days
Pantothenic acid

28. Name the nephritic disease based on the immunofluorescent staining - Smooth and linear pattern of IgG and C3 in the GBM
Spinal trigeminal nucleus
Nodular sclerosis
Posterior chamber
Goodpasture disease

29. What is the venous and arterial stretch receptors' function regarding the secretion of ADH?
They chronically inhibit ADH secretion; when there is a decrease in the blood volume - the stretch receptors send fewer signals - and ADH is secreted.
Major
Fentanyl
Left: stomach - spleen - and left kidney; right: liver - duodenum - and right kidney

30. During What embryonic week does the intraembryonic coelom form?
Third week
Upper outer quadrant (left more than right)
Aminoacyl - tRNA synthetase - which uses 2 ATPs for this reaction.
Incidence rate

31. Has analgesic and antipyretic activities but lacks anti - inflammatory effects.
Squamous cell carcinoma
Fragile X syndrome
Breast
Acetaminophen

32. What AA is a precursor of the following substances? - NAD
Wiskott - Aldrich syndrome
Tryptophan
Nitroblue tetrazolium reduction test (NBT). It is negative in patients with CGD because there is no production of oxygen radicals.
Voltage - gated calcium channel

33. What happens to V/Q ratio if a thrombus is lodged in the pulmonary artery?
Afferent pupillary defect (CN II lesion); in an efferent pupillary defect (CN III) - B/L constrict when light is shined in the unaffected eye and consentual pupil constriction occurs when light is shined in the affected eye.
Regardless of the rate of infusion - it takes 4 to 5 half - lives to reach steady state.
The V/Q ratio increases - since the area is ventilated but hypoperfused as a result of the occlusion.
Conn syndrome (primary hyperaldosteronism)

34. What cell membrane structure increases the surface area of a cell and has actin randomly assorted within its structure?
Cleft palate
5- hydroxyindoleacetic acid (5- HIAA)
Microvillus
It decreases insulin secretion.

35. What two pathologic conditions occur when the gut does not return to the embryo?
Transcription (C comes before L in the alphabet - and transCription comes before transLation)
Extrahepatic biliary atresia
Omphalocele and gastroschisis
Secondary hypoparathyroidism (vitamin D toxicity)

36. What color do fungi stain with PAS? Silver stain?
Pasteurella - Brucella - Legionella - and Francisella (all of the - ellas)
IgE
Hot pink with PAS and grey to black with silver stain
Area 17

37. Name the hepatitis virus based on the following information - Enveloped DNA hepadnavirus
eIF-2 in the P site
3 years old
Hepatitis B
The placenta

38. What molecule that is needed to trigger T cell activation is noncovalently linked to TCR?
Cestodes
CD3 molecule. It transmits signals to the inside of the T cell to trigger activation
Chronic end - stage renal disease
Utricle and saccule

39. The DSM- IV- TR is scored on the basis of five axes of diagnosis. In What axis would you place x Global assessment of function?
Spectinomycin
Because incidence is defined as new events; treatment does not decrease the number of new events. It does decrease the number of individuals with the event (prevalence would decrease).
Pancreatic insufficiency
Axis V

40. What is the term for processing an APC's pinocytosed material by fusing with a lysosomal granule and cleaving the Ag into peptide fragments?
Middle meningeal artery
Brucella and Listeria (has tumbling motility)
Ag processing; it is needed for class I molecules. Class II molecules have an invariant chain that protects them from breakdown.
Cones (C for color and cones)

41. What thalamic relay nucleus do the mammillary bodies project to?
Membranoproliferative glomerulonephritis (MGN)
Passive - aggressive
The anterior nucleus of the thalamus
HBsAb IgG

42. At What age do children begin to understand the irreversibility of death?
At 8 to 9 years of age. Prior to this age they view death as a form of punishment.
Myeloschisis All except occulta cause elevated - fetoprotein levels.
Melanocytes
Bordetella pertussis

43. Which is the conditioned response - the conditioned stimulus - the unconditioned response - the unconditioned stimulus in this case? A patient has blood withdrawn and faints. The next time she goes to have blood taken - she faints at the sight of the
HBcAb IgG - HBV- DNA - HBeAg - HBsAg
The blood withdrawn is the unconditioned stimulus - inducing the unconditioned response (fainting). The needle is part of the blood - drawing procedure and is the conditioned stimulus (unconditioned and conditioned stimuli are paired) resulting in th
Phosphofructokinase -1 and costs 1 ATP
150 mcg/day is the minimal daily intake needed. Most people ingest 500 mcg/day.

44. Caf
Adenosine deaminase (ADA) deficiency
Neurofibromatosis
Dapsone
CN IV

45. What nonmotile gram - negative - non - lactose - fermenting facultative anaerobic rod uses the human colon as its only reservoir and is transmitted by fecal - oral spread?
Shigella
Dopamine
Proline and lysine
Caput medusa - internal hemorrhoids - esophageal varices - retroperitoneal varices - and splenomegaly

46. What three structures are in contact with the left colic flexure? With the right colic flexure?
Left: stomach - spleen - and left kidney; right: liver - duodenum - and right kidney
Exogenous steroids suppress LH release and result in Leydig cell atrophy. Testosterone - produced by Leydig cells - is needed for spermatogenesis.
Propofol
10% are bilateral - 10% malignant - and 10% familial - 10% in children - and 10% outside the adrenal gland

47. Gas gangrene is associated with which Clostridium species?
Clostridium perfrigens
Hepadnavirus
1. Benefits of the procedure 2. Purpose of the procedure 3. Risks of the procedure 4. The nature of the procedure (what you are doing) 5. The alternative to this procedure and its availability (Don't forget the last one; this is where physicians get
1. Increase compliance 2. Decrease surface tension 3. Decrease probability of pulmonary edema formation

48. What is the name of the major chemotactic agent released from x The blood serum? (Hint: it is a complement factor.)
C5a
Resistance decreases as resistors are added in parallel.
Mentally disabled
The bifurcation of the abdominal aorta

49. What is the term to describe homosexuals who x Are uncomfortable with their own person and disagree with their sense of self?
The bifurcation of the abdominal aorta
2.0 or greater
Ego dystonic
There would be two Fab and Fc regions.

50. Name the antidote - Lead
H 2
Boutonni
Penicillamine - EDTA (calcium disodium edetate) - or dimercaprol
Ascaris lumbricoides