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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. How many ATPs per glucose are generated in glycolysis?
Subacute combined degeneration of the spinal cord is treated with IM vitamin B12 injections. If treatment is working - you will see an increased reticulocyte count on the peripheral smear in about 5 days.
38 ATPs if aerobic - 2 ATPs if anaerobic (36 ATPs[malate shuttle] + 4 ATPs[Glycolysis] - 2 ATPs[phosphorylate glucose] = 38 ATPs)
Chloramphenicol
Heparin - intrinsic pathway - PTT; warfarin - extrinsic pathway - PT (mnemonic: hPeT - wPiTT)

2. What are the three signs of morphine overdose?
The parasympathetic nervous system
1. Pinpoint pupils 2. Decreased respiratory rate 3. Coma
Macula densa
Secondary hypothyroidism/pituitary (Low TSH results in low T4 and increased TRH because of lack of a negative feedback loop.)

3. How do the corticobulbar fibres of CN VII differ from the rest of the CNs?
QRS complex
Normally corticobulbar fiber innervation of the CNs is bilateral (the LMN receives information from both the left and right cerebral cortex) - but with CN VII the LMN of the upper face receives bilateral input but the lower facial LMNs receive only c
Hurler syndrome and Hunter syndrome - respectively
300 mOsm/L

4. Which three factors cause the release of epinephrine from the adrenal medulla?
Nephrotoxic oxylate stones
Graves disease
1. Exercise 2. Emergencies (stress) 3. Exposure to cold (The three Es)
Molindone

5. By which process do Abs make microorganisms more easily ingested via phagocytosis?
Neisseria meningitides
One day after the LH surge and 2 days after the estrogen peak.
Splitting of the first heart sound occurs during inspiration because of the increased output of the right ventricle - delaying the closure of the pulmonic valve.
Opsonization

6. What disorder is associated with decreased platelet count - prolonged PT and PTT - decreased fibrinogen - and increased fibrin split products (D- dimers)?
Disseminated intravascular coagulation (DIC)
Epinephrine
The Babinski reflex is present in UMN lesions. Muscle atrophy due to disuse - hyperreflexia - spastic paralysis - increased muscle tone - and weakness are commonly seen in UMN lesions.
1. Bunyavirus 2. Orthomyxovirus 3. Arenavirus 4. Reovirus Remember BOAR

7. Which genus of dermatophytes is associated with the following sites of infection? - Nails and skin only
Skeletal muscles
Progestin
Epidermophyton
Zero - order elimination

8. What two classes of drugs can cause schizoid behavior?
Glucocorticoids and amphetamines
Kayser - Fleischer rings
Tetracycline
Sadism

9. Name the hypochromic microcytic anemia based on the following laboratory values - Increased iron - decreased TIBC - increased percent saturation - increased ferritin
Xanthine - hypoxanthine - theophylline - theobromine - caffeine - and uric acid are all purines.
Preoperational (2-6 years)
Neisseria meningitides
Sideroblastic anemia

10. Name the ocular lesion; be specific - A right LGB lesion (in the thalamus)
Left homonymous hemianopsia
Glucocorticoids and amphetamines
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
Melasma

11. Which class of antiarrhythmics are Beta- blockers?
Class II
Cirrhosis and hemolytic anemia - which are risk factors for pigmented gallstones.
Autoimmune thrombocytopenia purpura
Hypoparathyroidism

12. There are no persistent infections with...
Pneumotaxic center (short - fast breaths)
naked viruses
Both
Liver - kidney - and GI epithelium

13. Are contraindicated in patients with SCID.
Beta- Galactosidase
Western blot
Chromosome 15
Live vaccines

14. What is the only way to increase maximum velocity (Vmax)?
Insulin
Increase enzyme concentrations
Elongation factor - G and GTP
Menses

15. What type of symptoms in schizophrenia are associated with x Muscarinic receptors (ACh)?
1. Masseter 2. Temporalis 3. Medial pterygoid 4. Lateral pterygoid
Type II symptoms (negative); otherwise healthy persons have them - but schizophrenics do not.
Mitral valve closure indicates the termination of the ventricular filling phase and beginning of isovolumetric contraction.
Barrett esophagus has an increased risk of developing adenocarcinoma of the esophagus.

16. What is the most common one? - Malignant tumor in women
Staphylococcus aureus
Breast
1. Petechiae 2. Hyperactive mental status 3. Occurrence within 24 to 48 hours of the initial insult (e.g. - long bone fracture)
Cholera toxin

17. Which kidney is lower? Why?
Hepatitis A (infectious)
The right kidney is lower in the abdominal cavity because of the amount of space the liver occupies.
Proximal tubule
Anemic patients have a depressed O2 content because of the reduced concentration of Hgb in the blood. As for polycythemic patients - their O2 content is increased because of the excess Hgb concentrations.

18. Name the ocular lesion; be specific - Right calcarine cortex lesion
Right - sided valves
Human chorionic somatomammotropin (hCS) or human placental lactogen (hPL)
90% of benign myxomas arise within the left atrium near the fossa ovalis.
Left homonymous hemianopsia

19. What is the term when the brachial artery is compressed - resulting in ischemic contracture of the hand?

20. What bonds are broken by endonucleases?

21. What is the effect of T3 on heart rate and cardiac output?
Corticosteroid
Antithyroglobulin and antimicrosomal Abs
Oxazepam - temazepam - and lorazepam ( OTL - Outside The Liver)
T3 increases both heart rate and cardiac output by increasing the number of Beta - receptors and their sensitivity to catecholamines.

22. What is the DOC for CMV retinitis?
Birth defects - low birth weight (< 1500 g) with neonatal respiratory distress syndrome (NRDS) - and SIDS
Ganciclovir
Alzheimer's (dementia of Alzheimer's type - DAT). (Remember - Alzheimer's constitutes 65% of dementias seen in patients 65 years old.)
Cytochrome a/a3

23. What part of the heart forms x Superior border?
Marrow failure - cancer - and leukemia
Parvovirus
Conus arteriosus of the right ventricle and right and left auricles
Type II

24. Name the hypochromic microcytic anemia based on the following laboratory values - Decreased iron - TIBC - and percent saturation; increased ferritin
Anemia of chronic disease
Four high energy bonds - two from ATP in AA activation and two from GTP
Meningocele All except occulta cause elevated - fetoprotein levels.
Bioavailability

25. Is irreversible
Type II hypersensitivity (cytotoxic)
Frontal lobe
Estrone
Ag - Ab binding

26. Name the primary vesicle the following structures are derived from (proencephalon - mesencephalon - or rhombencephalon) - Pineal gland
Undoing
Hematoxylin
Fibrocystic change of the breast
Proencephalon diencephalon derivative

27. What is the most common one? - Location of ependymomas in children
1. Nails 2. Hair 3. Sweat glands (both apocrine and sebaceous)
In children - the fourth ventricle; in adults - the lateral ventricle or spinal cord
Because they do not block D2A receptors - they are antagonists of 5HT2 receptors.
Dysmetria; this is seen in a finger - to - nose test.

28. What oral hypoglycemic agent should be used with caution in patients with CHF because it causes lactic acidosis?
Axis II
REM latency; normally it is about 90 minutes.
Adjustment disorder. It is a diagnosis of exclusion (used if no other choice).
Metformin

29. Clarke's nucleus is the second ascending sensory neuron of which spinocerebellar tract?
3'-5' direction - synthesizing RNA in the 5'-3' direction
Gain of hypotonic fluid (water intoxication or hypotonic saline)
The thyroid gland
Dorsal spinocerebellar tract; the accessory cuneate nucleus is the second nucleus for the cuneocerebellar tract.

30. What form of renal tubular reabsorption is characterized by low back leaks - high affinity of a substance - and easy saturation? It is surmised that the entire filtered load is reabsorbed until the carriers are saturated - and then the rest is excret
Sucralfate
The inner membrane of the mitochondria (cristae)
A transport maximum (Tm) system
Phase 4

31. What malignant tumor of the skin is associated with Birbeck granules?
Psammoma bodies
Hemangioma (benign)
Histiocytosis X
Kupffer cells

32. What is the size of the prokaryotic ribosome?
70S ribosomes in prokaryotes and 80S ribosomes in eukaryotes
Area 4
Albendazole
The rate of Beta- oxidation

33. What malignant neoplasm of the bone is associated with Homer - Wright pseudorosettes; onion skinning of the periosteum on radiographs of the femur - pelvis - and tibia; and chromosome 11;22 translocation?

34. What is the most common one? - Germ cell tumor of the ovary
Masochism
CD19
The folding of an AA chain
Dysgerminoma

35. What phase of the cell cycle are the following antineoplastic agents specific for? - Vincristine
It is produced by the preload on the muscle prior to contraction.
Respiratory depression
Proencephalon
Mitosis

36. What three chemical agents are associated with angiosarcomas of the liver?
Arsenic - thorotrast - and vinyl chloride
Afterload
Ipratropium
Lispro insulin

37. What two Beta2- agonists are used to produce bronchodilation?
CN VII
Inactivated; glucose results in decreased cAMP levels and therefore blocks protein binding between cAMP and CAP.
Metaproterenol and albuterol
The fastigial nucleus

38. Name the ocular lesion; be specific - Left optic nerve lesion
Arch of the aorta and right subclavian artery
The affinity of the drug for its receptor
Left eye anopsia (left nasal and temporal hemianopsia)
Isotypes

39. Based on operant conditioning - What type of reinforcement is described when x Adding a stimulus reinforces a behavior?
Mumps
ASA (salicylate)
Nondominant parietal lobe
Positive reinforcement

40. Name the form of spina bifida - Meninges project through a vertebral defect
The courts. These are legal - not medical terms.
Myasthenia gravis
Meningocele All except occulta cause elevated - fetoprotein levels.
Third M PITS for pharyngeal pouch derivatives

41. What two bacteria are associated with drinking unpasteurized milk?
Lithium
Cystadenocarcinoma
Brucella and Listeria (has tumbling motility)
The Romberg sign is present if the patient sways or loses balance when standing with eyes open. In a dorsal column lesion - patients sway with eyes closed. (Don't forget this one.)

42. What toxin ADP- ribosylates via Gi to increase cAMP?
Chromosome 15q
The deepest sleep levels (stage 3 and 4) occur mostly in the first half of sleep.
Pertussis toxin
Sphingomyelin (lecithin also - but it is not a sphingolipid)

43. Name the most common type or cause - Chronic metal poisoning
Lingual nerve of CN V3
Liver - kidney - and GI epithelium
Lead
16S subunit

44. What negative sense RNA virus is associated with intracytoplasmic inclusion bodies called Negri bodies?
Rabies
In the medulla; all the other structures are cortical.
HBcAb IgG - HBV- DNA - HBeAg - HBsAg
Superior

45. What is the term for different classes and subclasses of the same gene products?
Ea (activation energy)
Isotypes
Fluconazole
Frameshift

46. What syndrome is characterized by dynein arm abnormality resulting in chronic sinusitis - recurrent pulmonary infections - and infertility?

47. What form of antimicrobial therapy is best for an immunocompromised patient?
Bactericidal
Amantadine
Systolic interval decreases secondary to increased contractility; diastolic interval decreases secondary to an increase in heart rate.
Hepatitis D

48. What has occurred to the renal arterioles based on the following changes in the GFR - RPF - FF - and glomerular capillary pressure? - GFR ? - RPF ? - FF normal - capillary pressure ?
a - and Beta- chains are on most T cells.
Constriction of afferent arteriole
Iodine - resulting in congenital hypothyroidism
Increases Remember - the carotid sinus reflex attempts to compensate by increasing both TPR and heart rate. -------------------------------------------------------------------------------

49. What two viruses are associated with Reye's syndrome?
Varicella virus and influenza virus
Phallus
Inactivated; glucose results in decreased cAMP levels and therefore blocks protein binding between cAMP and CAP.
Polyarteritis nodosa

50. At What age do children begin to understand the irreversibility of death?
At least six
At 8 to 9 years of age. Prior to this age they view death as a form of punishment.
Foods rich in tyramine (e.g. - cheese - dried fish - sauerkraut - chocolate - avocados - and red wine) should be avoided. Hypertensive crisis occurs when tyramine and MAOIs are mixed.
Ataxia - telangiectasia