Test your basic knowledge |

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. A patient goes to the ER with abdominal cramps - vomiting - diarrhea - and sweating less than 24 hours after eating potato salad at a picnic; What is the most likely responsible organism?
Staphylococcus aureus
The one start codon - AUG - in eukaryotes codes for methionine and in prokaryotes formylmethionine.
Negative predictive value
Catalase - negative bacteria secrete H2O2 as a byproduct (remember - catalase breaks down H2O2) - allowing the neutrophils to use it as the substrate for the other toxic metabolites. Patients with CGD are prone to catalase - positive bacterial infect

2. What drug of choice for ascaris causes neuromuscular blockade of the worm?
Maxillary division of CN V and glossopharyngeal nerves
Pyrantel pamoate
The Halsted - Reitan battery. It consists of finger oscillation - speech sound perception - rhythm - tactual - and category testing.
No. Remember - tests do not diagnose - they confirm or refute your diagnosis. Also - diagnosis of MI requires two of three criteria: chest pain consistent and characteristic of MI - elevated cardiac enzymes consistent with MI - and ST segment elevati

3. What test uses p24 protein when diagnosing HIV?
Monosodium urate crystals
naked viruses
ELISA test
MstII; changing codon 6 (from A to T) destroys the restriction site.

4. A single mRNA strand translated by a ribosome is termed what?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

5. Does physiologic splitting of the first heart sound occur during inspiration or expiration? Why?
In the PNS - myelin is produced by Schwann cells - in the CNS by oligodendrocytes.
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.
Skeletal muscle
Estrogens are 18- carbon steroids. (Removal of one carbon from an androgen produces an estrogen.)

6. What cell type do cromolyn and nedocromil affect for prophylactic management of asthma via blockade?
Third week
Contralateral. The spinothalamic tract enters the spinal cord and immediately synapses in the dorsal horn - crosses over - and ascends contralateral in the spinal cord - brainstem - thalamus - and postcentral gyrus.
They prevent mast cell degranulation.
Intrinsic factor (IF)

7. Why is the cell's resting membrane potential negative?
The resting membrane potential of the cell is -90 mV because of the intracellular proteins.
Hodgkin lymphoma
Dopamine levels rise with waking; dopamine is associated with wakefulness.
Saltatory conduction

8. What is the MCC of the following meningitides? - In military recruits
Parietal cells (Remember - they secrete HCl - too.)
Neisseria meningitides
Leydig cells produce testosterone. LH stimulates Leydig cells. (Both start with L.)
Homeodomain proteins

9. What is the triad of Reiter syndrome?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

10. What form of bias occurs when the experimenter's expectation inadvertently is expressed to the subjects - producing the desired effects? How can it be eliminated?
Uroporphyrinogen III cosynthase
Pygmalion effect (experimenter expectancy). This can be eliminated with double - blind studies.
Primary biliary cirrhosis
The negative charge inhibits the filtration of protein anions.

11. In what cycle does glucose go to the muscle - where it is converted to pyruvate and then into alanine before being taken back to the liver?
Omega -3; linoleic is omega -6
Duodenum (all but the first part) 2. Ascending Colon 3. Ureters 4. Pancreas 5. Supra renal glands (adrenals) 6. Descending colon 7. Aorta 8. Kidneys 9. Rectum 10. IVC D CUpS DAKRI is the mnemonic - everything else is covered with peritoneum
presence of PMNs
Alanine cycle

12. At what vertebral level does the common carotid artery bifurcate?
Lispro insulin
C4 (the upper border of the thyroid cartilage)
Doxycycline and minocycline
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.

13. What operant conditioning therapy or modification is described as x Reinforcing successive attempts that lead to the desired goal (gradual improvement)?
Shaping (successive approximation)
wave
H 1
GP IIb and IIIa receptors

14. Match the chromosome and haploid number with the stage of sperm development - spermatid - spermatocyte (primary or secondary) - spermatogonia (type A or B): x 46/2n (divide meiotically)
Fitz - Hugh - Curtis syndrome
Spermatogonia (type A)
Pimozide
The oncotic pressure of plasma promotes reabsorption and is directly proportional to the filtration fraction.

15. Which hepatitis B serology markers
HBcAb IgG - HBV- DNA - HBeAg - HBsAg
Hepatocellular carcinoma
Janeway lesions
a1- Receptors

16. How many segments in a neutrophilic nucleus are necessary for it to be called hypersegmented?
Suppression
Beta- Endorphin
At least 5 lobes
Passive - aggressive

17. Name the MCC of death - In neonates
Heart disease
Granulosa/thecal cell tumor of the ovary
Pseudomonas
Neonatal respiratory distress syndrome (NRDS)

18. What are the two MCC of acute epididymitis in males? - More than 35 years old
Escherichia coli and Pseudomonas sp.
The subclavian artery
Ascorbic acid (vitamin C) deficiency (These are the signs of scurvy.)
The stapedius muscle

19. What type of symptoms in schizophrenia are associated with x Muscarinic receptors (ACh)?
Collecting ducts - which make them readily permeable to water reabsorption.
Circumvallate papillae
Type II symptoms (negative); otherwise healthy persons have them - but schizophrenics do not.
1. Temporal 2. Zygomatic 3. Buccal 4. Mandibular 5. Cervical (Two Zebras Bit My Clavicle.)

20. How is sleep affected in a person with alcohol intoxication?
DNA polymerases
Decreased REM sleep and REM rebound during withdrawal
P1 protein
Second M PITS for pharyngeal pouch derivatives

21. What two viruses are associated with Reye's syndrome?
Varicella virus and influenza virus
Bilateral degeneration of the dorsal columns in the spinal cord secondary to syphilis is known as tabes dorsalis. A high - step gait is seen in patients with tabes dorsalis because of the inability to feel the ground beneath their feet.
Hormone - sensitive lipase
Musculocutaneous nerve

22. Regarding the Lac operon - for What do the following genes code? - A gene
Squamous cell carcinoma
Increase (5- HT and dopamine levels do the same)
Thiogalactoside transacetylase
Clostridium perfringens

23. What pathology is associated with podagra - tophi in the ear - and PMNs with monosodium urate crystals?
HPV
Caplan syndrome
Gout
Coronary circulation

24. Name the ocular lesion; be specific - Left Meyer's loop lesion of the optic radiations.
Left homonymous hemianopsia
Duchenne muscular dystrophy
Musculocutaneous nerve
Phase 2

25. What chromosome 4 - AD disorder is a degeneration of GABA neurons in the striatum of the indirect pathway of the basal ganglia?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

26. What phase of the cell cycle are the following antineoplastic agents specific for? - Bleomycin
Brucella
Ferrochelatase
G2 phase
Depolarization (i.e. - Na+ influx)

27. If you double the infusion rate of a drug - how long will it take to reach steady state?
Iron deficiency anemia
Regardless of the rate of infusion - it takes 4 to 5 half - lives to reach steady state.
Leuprolide
High - frequency sound waves

28. What is the DOC for treating Entamoeba histolytica - Giardia - Trichomonas - Bacillus fragilis - and Clostridium difficile infections?
Vancomycin
80S ribosomes (because they are eukaryotic)
PRPP aminotransferase
Metronidazole

29. What are the pharmacologic effects seen sexually with x Neuroleptics?
Glycine/arginine
Erectile dysfunction
Resistance increases as resistors are added to the circuit.
CN VI - VII - and VIII

30. Does the zygote divide mitotically or meiotically?
Pseudomonas sp.
EF- G of the 50S subunit
The zygote divides mitotically; only germ cells divide meiotically.
Penicillin V

31. What is the term for chronic necrotizing pulmonary infections resulting in permanent airway dilation and associated with Kartagener syndrome?
Glossopharyngeal nerve
Bronchiectasis
Frontal eye field (Brodmann area 8)
Thyroid gland

32. What hormone is characterized by the following renal effects? - Calcium reabsorption - phosphate reabsorption
Proencephalon diencephalon derivative
H 1
Chondroitin sulfate and keratan sulfate
Vitamin D3

33. What is used as an index of cortisol secretion?
Proximal tubule
RBCs
Selection bias
Urinary 17- OH steroids

34. Which form of melanoma carries the worst prognosis?
Nodular melanoma
300 mOsm/L
CN XI and X
Vitamin K

35. What is the name of the benzodiazepine antagonist used in the treatment of an overdose?
Flumazenil
Free polysomes. Membrane - associated polysomes are the site of protein synthesis destined to leave the cell.
1. Flow independent of BP 2. Flow proportional to local metabolism 3. Flow independent of nervous reflexes
The fasciculus gracilis (Graceful) - which lies closest to the midline of the spinal cord.

36. Name the macrophage based on its location: x Liver macrophages
Bronchogenic carcinoma
Kupffer cells
Vancomycin
Magnesium

37. What hormone causes milk letdown?
Bulbus cordis
Oxytocin
Exogenous steroids suppress LH release and result in Leydig cell atrophy. Testosterone - produced by Leydig cells - is needed for spermatogenesis.
LDL

38. What is the most common one? - Benign GI tumor
Leiomyoma
Autosomal recessive
Adenosine deaminase
Lumbar splanchnics

39. What serotonin reuptake inhibitor's major sexual side effect is priapism?
Cushing's ulcers
Lactulose
Severe combined immunodeficiency disease
Trazodone

40. Which benzodiazepine is most commonly used IV in conscious sedation protocols?
Antimicrobial agents
Midazolam
The energy of activation (Ea)
Myasthenia gravis

41. Inhibition of peripheral aromatic amino acid decarboxylase and increased CNS availability of L- dopa are results of what drug used in the treatment of Parkinson's disease?
Carbidopa and benserazide
PTH
12 ATPs per acetyl CoA that enter the tricarboxylic acid (TCA) cycle (Krebs cycle)
Clavicle - acromion - and glenoid fossa of the scapula and the humerus

42. What pathophysiologic disorder is characterized by the following changes in cortisol and ACTH? - Cortisol decreased - ACTH decreased
Secondary hypocortisolism (pituitary)
Streptococcus pneumoniae
Free - unprocessed Ag
Lead - time bias (remember - patients don't live longer with the disease; they are diagnosed sooner.)

43. Movement disorders are associated with what dopamine pathway (What part of the brain)?
Nephroblastoma
Central/neurogenic diabetes insipidus; in the nephrogenic form there is sufficient ADH available - but the renal collecting ducts are impermeable to its actions.
Fatty acids cannot cross the blood - brain barrier; therefore - they cannot be used as an energy source.
Nigrostriatal pathways (basal ganglia)

44. What is the term for headaches - inability to concentrate - sleep disturbances; avoidance of associated stimuli; reliving events as dreams or flashbacks following a psychologically stressful event beyond the normal range of expectation?
Posttraumatic stress disorder. (Important: symptoms must be exhibited for longer than 1 month.)
Mesencephalic nucleus
Volkmann's contracture
eEF-2 is the site where Pseudomonas and Diphtheria toxins work.

45. Where are the LMN cell bodies of the corticospinal tract?
In the ventral horn of the spinal cord. UMN cell bodies are in the precentral gyrus of the frontal lobe.
Missense
Campylobacter jejuni
Clavicle - acromion - and glenoid fossa of the scapula and the humerus

46. What are the three causes of transudate?
Reticulocyte
Meningococcus (Gonococcus does not)
Libman - Sacks endocarditis
CHF - cirrhosis - and nephrosis

47. What is the only dsRNA virus?
Reovirus
M12 strains
Secondary hypothyroidism/pituitary (Low TSH results in low T4 and increased TRH because of lack of a negative feedback loop.)
Confounding bias

48. What is the only encapsulated fungal pathogen?
Cryptococcus
Follicular lymphoma
Pseudomembranous colitis
LDL

49. What scale assesses a rank order classification but does not tell the difference between the two groups?
Agglutination test
Ordinal scale (e.g. - faster/slower - taller/shorter)
Endometrial cancer
Hypermyelination of the corpus striatum and the thalamus (seen in cerebral palsy)

50. From What aortic arch are the following structures derived?
Degenerates
CML and All
4 years old
Posterior interventricular artery