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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. Starry sky pattern
Middle meningeal artery
Burkitt lymphoma
Chromosome 11p
Phase 4; NE increases the slope of the prepotential - allowing threshold to be reached sooner - and increases the rate of firing.

2. What is the term for chronic necrotizing pulmonary infections resulting in permanent airway dilation and associated with Kartagener syndrome?
Serotonin
Upper outer quadrant (left more than right)
Bronchiectasis
Twelve pairs through twelve thoracic vertebrae. Totaling 31 pairs of spinal nerves.

3. What bacterium is responsible for woolsorter's disease?
Reovirus
Convergence
Bacillus anthracis
HPVs 16 and 18

4. Who is responsible for passing on mitochondrial DNA genetic disorders?
1. Sweat glands 2. Arterioles 3. Veins
Peutz - Jeghers syndrome
Mitochondria - linked disorders are always inherited from the mother.
MGN

5. What form of estrogen is of placental origin?
The increased H+ moves intracellularly and is buffered by K+ leaving the cells - resulting in intracellular depletion and serum excess. (Intracellular hypokalemia is the reason you supplement potassium in diabetic ketoacidosis - even though the serum
Estriol
Accommodation
Schistosoma haematobium

6. What cell type of the bone has PTH receptors?
Osteoblasts - which in turn stimulate osteoclasts to break down bone - releasing Ca2+ into the interstitium. (Remember - blasts make - clasts take.)
18 years old (except if emancipated)
Insulin
Down syndrome

7. What ocular muscle x Depresses and abducts the eyeball?
Addition (They are mutually exclusive.)
Superior Oblique (CN IV) (LR6 SO4)3
Fibrocystic change of the breast
Demeclocycline

8. How many covalent bonds per purine - pyrimidine base pairing are broken during denaturation of dsDNA?
Cortisol Remember - from the outer cortex to the inner layer - Salt - Sugar - Sex. The adrenal cortex gets sweeter as you go deeper.
The number of cross - bridges cycling during contraction: the greater the number - the greater the force of contraction.
Eclipse period
None. Denaturation of dsDNA breaks hydrogen bonds - not covalent bonds.

9. By What age should children be able to draw the following figures? - Square
Temporal arteritis (giant cell arteritis)
5 years old
50%. The uncles and older siblings are the most likely perpetrators - although stepfathers also have a high rate.
The granule cell. Its neurotransmitter is glutamic acid - Which is also the principal neurotransmitter of the visual pathways.

10. What highly undifferentiated aggressive CNS tumor of primordial neuroglial origin develops in children and is associated with pseudorosettes?
Primitive neuroectodermal tumors (i.e. - medulloblastomas and retinoblastomas)
Femoral hernias
MHC class I antigens; they are also found on the surface of platelets.
Tertiary hypothyroidism/hypothalamic (Low TRH causes all the rest to be decreased because of decreased stimulation.)

11. What is the most common one? - Cancer of the esophagus in the world
IgA
Squamous cell carcinoma
Lentigo maligna melanoma
Hypokalemic metabolic alkalosis occurs from vomiting because of the loss of H+ - K+ - and Cl -.

12. At high doses aspirin has ________ properties.
Anterior tibial artery
Intussusception
Uricosuric
The one start codon - AUG - in eukaryotes codes for methionine and in prokaryotes formylmethionine.

13. What CNs are affected if there is a lesion in x The upper pons?
Hapten (not immunogenic)
Excretion is greater than filtration for net secretion to occur.
CN V
Dysplasia

14. What is the most common one? - Cardiac pathology in patients with SLE
Adenocarcinoma (30% to 35%)
Fibrinous exudates
Libman - Sacks endocarditis
Pregnancy

15. Name these cluster A personality disorders: x Baseline mistrust; carries grudges; afraid to open up; uses projection as defense mechanism; lacks hallucinations or delusions
Posterior interventricular artery
LTB4
Paranoid
A Ghon focus is a TB tubercle - whereas a Ghon complex is a focus with hilar lymph node involvement.

16. What two compensatory mechanisms occur to reverse hypoxia at high altitudes?
Increase in erythropoietin and increase in 2 - 3- BPG - also called 2 - 3- diphosphoglycerate (2 - 3- P2Gri) (increase in glycolysis)
Pyelonephritis
Functionally they are part of the left lobe of the liver because they receive their blood supply from the left hepatic artery. Anatomically they are considered part of the right lobe of the liver.
Primary polydipsia; patients with diabetes insipidus will continue to produce large volumes of dilute urine.

17. What is the term for white retinal spots surrounded by hemorrhage? In what condition are they seen?
Roth spots - and they are seen in bacterial endocarditis.
Anopheles mosquito
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
Aminoacyl - tRNA synthetase - which uses 2 ATPs for this reaction.

18. What is the DOC for esophageal candidiasis?
Fluconazole
H 1
Positive sense RNA means it can serve as mRNA and therefore has 5'-3' polarity
Adenocarcinoma (30% to 35%)

19. What stage of male development is characterized by the following LH and testosterone levels? - LH pulsatile amplitude and levels increase - with increased testosterone production.
Interferons
Puberty
C5a
Allelic exclusion. It is to ensure that one B cell produces only one Ab.

20. What disease that involves mental retardation - flat face - muscle hypotonia - and a double - bubble sign on radiograph poses an increased risk of Alzheimer's disease and All?
Hepatitis A
Down syndrome (trisomy 21)
Posterior
Splenomegaly and anemia (with a high index of suspicion)

21. All AAs have titration plateaus At what pH values?
DM - hypercholesterolemia - smoking - and HTN are major risk factors. Being male - obesity - sedentary lifestyle - homocysteine elevation - oral contraceptive pills - and genetics are minor risk factors for atherosclerosis.
Teratoma (dermoid cyst)
Allograft
pH of 2 and 9

22. Up to How many hours post ejaculation do sperm retain their ability to fertilize the ovum?
Up to 72 hours; the ovum losses its ability to be fertilized 8 to 25 hours after release.
Autism. Head - banging - rocking - and self - injurious behaviors are also common in autism.
Squamous cell carcinoma
Dorsal motor nucleus of CN X

23. Soap bubble appearance on radiograph
Goodpasture syndrome
Giant cell tumor of the bone
Beta- Galactosidase
Ciliary ganglion

24. Is not found in smooth muscle - liver - and the kidneys.
Helicase (requires ATP for energy)
Herpesvirus
Catechol - O- methyl transferase (COMT)
Brain abscess

25. What are the three branches of the celiac trunk?
Type 2
The left gastric - splenic - and common hepatic arteries
Enterokinase
Gardnerella vaginalis

26. What part of the 30S ribosome binds to the Shine - Dalgarno sequence?
Dendritic cells - macrophages - and thymic epithelial cells
Posterior cruciate ligament
Histamine
16S subunit

27. Name the type of necrosis - Due to lipase activity and has a chalky white appearance
Osteogenesis imperfecta
PR interval
Fat necrosis
extrapyramidal dysfunction

28. What are the three tissues where triacylglycerols are produced?
Graves disease
Fanconi - like syndrome
Median (think of it as the halfway point)
1. Liver 2. Muscle 3. Adipose tissue

29. What CN is associated with the x Fifth pharyngeal arch?
None; it degenerates.
Beta- Galactosidase
Schistosoma haematobium
Crohn disease

30. Name the area of the cerebral cortex with the function described: x Speech; critical for personality - concentration - initiating and stopping tasks (do one thing and begin a new without completion of the first) - abstract thought - and memory and hi
Parietal lobe
Oxytocin
All (nearly 15-20 times the normal risk)
Frontal lobe

31. What is the term for an inhibitory interneuron?
Toxoplasmosis
Small cell carcinoma (oat cell)
Gonads
Renshaw neuron

32. Name the most common type or cause - Infantile diarrhea
Rotavirus
One pair with three to five coccygeal vertebrae. Totaling 31 pairs of spinal nerves.
Antithyroglobulin and antimicrosomal Abs
Carbamazepine

33. How many ATPs are produced from cytoplasmic NADH oxidation using the glycerol phosphate shuttle?
Mitosis
2 ATPs by oxidative phosphorylation
First - pass metabolism and acid lability
Phenytoin

34. What is the confirmatory test for HIV?
alpha2- Receptors
0.21; it is a fancy way of saying 21% of the air is O2.
Western blot
Avoidant

35. What three major cell lines participate in the acquired immune system?
Parafollicular C cells
T cells - B cells - and macrophages
The one start codon - AUG - in eukaryotes codes for methionine and in prokaryotes formylmethionine.
Postinfectious GN

36. Are salivary secretions hypertonic - hypotonic - or isotonic?
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.
Fanconi - like syndrome
PTH
Hypotonic - because NaCl is reabsorbed in the salivary ducts

37. What level of mental retardation is characterized by x Having the ability to communicate and learn basic habits but training is usually not helpful?
Primary polydipsia; patients with diabetes insipidus will continue to produce large volumes of dilute urine.
Severe (range 20-34)
Prolactin
Hypertrophy

38. What CNs are affected if there is a lesion in x Pontomedullary junction?
Heparin - intrinsic pathway - PTT; warfarin - extrinsic pathway - PT (mnemonic: hPeT - wPiTT)
Down syndrome (it is slightly more common than fragile X syndrome.)
STARS 1. Upper Subscapularis 2. Thoracodorsal 3. Axillary 4. Radial 5. Lower Subscapularis
CN VI - VII - and VIII

39. Which hepatitis strain is a defective virus that can replicate only inside HBV- infected cells?
At least 15%
Hepatitis D
Increase in erythropoietin and increase in 2 - 3- BPG - also called 2 - 3- diphosphoglycerate (2 - 3- P2Gri) (increase in glycolysis)
Spironolactone (binds to aldosterone receptors)

40. What is the most common circulation Ig in the plasma?
Transient ischemic attack
Intrinsic factor (IF)
IgG
Magnesium

41. Which hepatitis B Ab indicates low transmissibility?
HBeAb
Klebsiella pneumoniae
Clearance
Area 22 and occasionally 39 and 40

42. At What age does IQ stabilize?
From age 5 onward IQ stabilizes.
Acute cystitis
Rhombencephalon
Serous exudates

43. What reflex increases TPR in an attempt to maintain BP during a hemorrhage?
Bile salts are actively reabsorbed in the distal ileum.
Mitochondria
Exposure
The carotid sinus reflex

44. What is the term for occlusion of a blood vessel due to an intravascular mass that has been carried downstream?
Herpes virus
Embolism
Spironolactone
Elongation factor - G and GTP

45. From What embryonic structure are the following structures derived? - The aortic vestibule and the conus arteriosus
Five pairs through five lumbar vertebrae. Totaling 31 pairs of spinal nerves.
Bulbus cordis
Obstructive lung disorders. The opposite changes (where you see decrease exchange it for increase and vice versa) are seen in a restrictive pattern.
Transitional cell carcinoma

46. Name the macrophages by location: x Kidney
Mesangial macrophages
The number of Ags that the Ab can bind
Kl
Frontal lobe syndrome (lesion in the prefrontal cortex)

47. What inflammatory bowel disorder is continuous - with extensive ulcerations and pseudopolyps - and is associated with HLA- B27?
Galactose and glucose
Ulcerative colitis
Hemostasis
Mast cells

48. What is the MCC of death in black males aged 15 to 24?
Squamous cell carcinoma (skin - lung) and angiosarcoma of the liver
Primase
They are in ganglia in the PNS.
Homicide. It is also the leading cause of death in black females aged 15 to 24.

49. What prokaryotic positioning enzyme in translation is blocked by the following? - Erythromycin
Ureaplasma urealyticum
Labile
Direct fluorescent Ab test
EF- G of the 50S subunit

50. What part of the ANS (i.e. - PNS or CNS) controls the constriction of the pupil in response to light?
IgD; IgM is also correct.
Transketolase and transaldolase. The reactions they catalyze are reversible.
Proencephalon
Parasympathetic