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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 substrate builds up in Tay- Sachs disease?
Yolk sac tumor
robenecid - a uricosuric agent
GM2 ganglioside Caused by a deficiency of Beta- hexosaminidase A
Osteoblasts - which in turn stimulate osteoclasts to break down bone - releasing Ca2+ into the interstitium. (Remember - blasts make - clasts take.)

2. What is the term for the pH range where the dissociation of H+ occurs?
Somatization disorder
Coombs test
pK (think of it as where half is base and half is acid)
Week four - and they remain dormant there until puberty.

3. Name the most common type or cause - Meningitis in adults
Rhombencephalon
MstII; changing codon 6 (from A to T) destroys the restriction site.
Motilin
Pneumococcus

4. What is the size of a positive PPD test for the following? (Reactive) x Healthy suburban male without any medical illnesses
Asbestosis
ELISA test
>15 mm
CN V1 - the occulomotor division of the trigeminal nerve - is the sensory component of the corneal reflex.

5. What direction does the primitive gut rotate? What is its axis of rotation?
The gut rotates clockwise around the superior mesenteric artery.
The CD4 T cell; the APC is the first cell in the immune response.
The short arm of chromosome 6
Anterior nuclear group (Papez circuit of the limbic system)

6. Circulating levels of what hormone cause the cervical mucus to be thin and watery - allowing sperm an easier entry into the uterus?
Leiomyoma
Estrogen
The V/Q ratio increases - since the area is ventilated but hypoperfused as a result of the occlusion.
Chromomycosis

7. What protein allows Mycoplasma to attach to the respiratory epithelium?
Endometriosis
P1 protein
The lung will expand; also the opposite is true.
Plummer - Vinson syndrome

8. What is the major muscle used in the relaxed state of expiration?
Under resting conditions expiration is considered a passive process; therefore - no muscles are used. In the active state the abdominal muscles can be considered the major muscle of expiration.
Megaloblasts
Yohimbine
Howell - Jolly bodies

9. What is the primary risk factor for suicide?
Ticlopidine or clopidogrel
Oxygen
Constipation and miosis
Previous suicide attempt

10. What would be the result if an Ab were cleaved with papain?
Langerhans cells
There would be two Fab and Fc regions.
ASA (salicylate)
1. C5a 2. Leukotriene B4 3. IL-8 4. Bacterial peptides

11. What IL is important in myeloid cell development?
First - pass effect
1 day prior to ovulation
IL-3 (3 face down is an M)
Bronchogenic carcinoma

12. What is the term for the force the ventricular muscle must generate to expel the blood into the aorta?
Constrictor pupillae and ciliary muscles
Chloramphenicol
Adenocarcinoma (30% to 35%)
Afterload

13. What syndrome causes inability to concentrate - easy distractibility - apathy - and regression to an infantile suckling or grasping reflex?
Type I error (alpha error). (Remember it as saying something works when it doesn't.) The chance of a type I error occurring is the P value.
Frontal lobe syndrome (lesion in the prefrontal cortex)
Antisocial
Reject it

14. Name the antimicrobial agent whose major side effect is listed - Altered folate metabolism
Aldosterone Remember - from the outer cortex to the inner layer - Salt - Sugar - Sex. The adrenal cortex gets sweeter as you go deeper.
Leiomyoma
Trimethoprim
Varicella

15. What are the four capsular polysaccharides used in the Neisseria meningitides vaccine?
Glucocorticoids and amphetamines
In eukaryotes transcription occurs in the nucleus and translation in the cytoplasm.
Testicular feminization syndrome (Dude looks like a lady!)
Y - W-135 - and C and A capsular polysaccharides

16. WBCs in the urine
The energy of activation
Acute cystitis
Male pseudohermaphrodite (dude looks like a lady!)
Turner syndrome

17. What two factors are required for effective exocytosis?
Calcium and ATP are required for packaged macromolecules to be extruded from the cell.
Methionine (start) and tryptophan are the only two AAs with only one codon.
GH
4.7 L - 5% of body weight

18. What bones make up the acetabulum?
Corticosteroid
The rate of Beta- oxidation
Pubis - ilium - and ischium
Pott disease

19. What hormone excess brings about abnormal glucose tolerance testing - impaired cardiac function - decreased body fat - increased body protein - prognathism - coarse facial features - and enlargements of the hands and feet?
Birds
Increased secretion of GH postpuberty leading to acromegaly.
Chromosome 6
Beta- Galactosidase

20. Name the MCC of death - In diabetic individuals
Vertebra prominens (C7 in 70% of cases - C6 in 20% - T1 in 10%)
Ischemia
Lysosomal a -1 - 4- glucosidase
MI

21. From Where is the energy for gluconeogenesis derived?
Beta- Oxidation of fatty acids
Site 1
Fibrocystic change of the breast
Prolactin

22. What is the site of action of cholera toxin?
Cholera toxin irreversibly activates the cAMP- dependent chloride pumps of the small and large intestine - producing a large volume of chloride - rich diarrhea.
Psoriasis - ankylosing spondylitis - inflammatory bowel disease - and Reiter's syndrome
Clostridium perfringens
Saltatory conduction

23. What highly undifferentiated aggressive CNS tumor of primordial neuroglial origin develops in children and is associated with pseudorosettes?
hyperventilation
Primitive neuroectodermal tumors (i.e. - medulloblastomas and retinoblastomas)
Vitamin D
>10 mm

24. Are the following responses associated with histamines H1 or H2 receptor activation? - Edema
Planning and fine - tuning of voluntary skeletal muscle contractions. (Think coordination.) Remember - the function of the basal ganglia is to initiate gross voluntary skeletal muscle control.
T4; because of the greater affinity for the binding protein - T4 has a significantly (nearly fifty times) longer half - life than T3.
Vitreous humor
H 1

25. On what layer of the epidermis does all mitosis occur?
Malpighian layer (made up of the stratum basale and stratum spinosum)
20:1T4T3. There is an increase in the production of T3 when iodine becomes deficient.
Gonorrhea
Plummer - Vinson syndrome

26. Why should opioid analgesics be avoided for patients with head trauma?
Proencephalon
Bacillus anthracis
Ciliary ganglion. (These fibers are carried in CN III. Remember it like this:- ili - in ciliary ganglion looks like the III of CN III.)
Opioids cause cerebral vasodilation and can result in increased intracerebral pressure.

27. What are the three C's of a TCAD overdose?
Coma - convulsions - and cardiotoxicity
1. Conjunctivitis 2. Nongonococcal urethritis 3. Peripheral arthritis Can't see - can't wee - can't kick with your knee
Streptococcus agalactiae
Inferior Oblique (CN III) (LR6 SO4)3

28. What is the term for the heart's inability to maintain perfusion and meet the metabolic demands of tissues and organs?
Plasmodium malariae; the others are tertian.
1. Incompetent patient (determined by the courts) 2. Therapeutic privilege (in the best interest of the patient when he or she is unable to answer) 3. Waiver signed by the patient 4. Emergency
Calcarine sulcus
CHF

29. What three organs can be affected by Trypanosoma cruzi?
With arteriolar constriction both the flow and pressure downstream decrease.
Paramyxovirus
Neuroleptic malignant syndrome is a potentially life - threatening condition Which is treated with symptomatic support - bromocriptine - and dantrolene.
Heart - esophagus - and colon. Remember - you get megas: cardiomegaly - megaesophagus - and megacolon.

30. What cytokine do Th1 cells secrete to inhibit Th2 cell function?
Mesangial macrophages
Doxacurium
INF- gamma
Lung recoil - being a force to collapse the lung - increases as the lung enlarges during inspiration.

31. What serotonin reuptake inhibitor's major sexual side effect is priapism?
Low average
Long - term memory is impaired in hippocampal lesions; it is spared in medial temporal lobe lesions.
Trazodone
There would be a Fab' region; thus - it would still be able to participate in precipitation and agglutination.

32. What growth factors are chondrogenic - working on the epiphyseal end plates of bone?
Osteoma
Somatomedins (IGF-1)
Psoriasis - ankylosing spondylitis - inflammatory bowel disease - and Reiter's syndrome
NADPH oxidase is deficient - resulting in an inability to produce toxic metabolites.

33. Will a unilateral lesion in the spinothalamic tract result in a contralateral or ipsilateral loss of pain and temperature?
Impotence
PALS
Acute toxic or viral nephrosis
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.

34. What cancer is particularly likely to affect English chimney sweeps?
Mesonephric duct (ureteric bud)
Scrotal cancer - due to the high exposure to polycyclic aromatic hydrocarbons
Transient protein C deficiency - because of its relatively short half - life - may result if warfarin is instituted alone.
Naloxone - naltrexone

35. From What aortic arch are the following structures derived?
Methanol
Alzheimer disease
Degenerates
IgD; IgM is also correct.

36. What is the MCC of death in children aged 1 to 14 in the United States?
Accidents
Waldeyer's ring
Yolk sac tumor
There would be a Fab' region; thus - it would still be able to participate in precipitation and agglutination.

37. In a topographical arrangement of the cerebellar homunculus map - What area or lobe x Is involved in motor planning?
Lateral part of the hemispheres
Steroid synthesis - drug detoxification - triglyceride resynthesis - and Ca2+handling
Cestodes
Reverse transcriptase

38. What is the most likely organism causing cellulitis in a patient who was cut by an oyster shell?
Vibrio vulnificus
Eosin
Astrocytoma
1. Picornavirus 2. Calicivirus 3. Reovirus (Remember PCR)

39. If the AV difference is positive - is the substance extracted or produced by the organ?
CN V
Staphylococcus aureus
1. Intracellular receptors 2. Membrane receptors 3. Enzymes 4. Intracellular effectors
A positive AV difference indicates that a substance is extracted by the organ - and a negative difference indicates that it is produced by the organ.

40. Protein production - bile secretion - detoxification - conjugation - and lipid storage.
Secondary hypothyroidism/pituitary (Low TSH results in low T4 and increased TRH because of lack of a negative feedback loop.)
Androgens are 19- carbon steroids.
Projective drawing. The artistic form is irrelevant - but the size - placement - erasures - and distortions are relevant.
Functions of hepatocytes

41. What two AAs do not have more than one codon?
H 2
Methionine (start) and tryptophan are the only two AAs with only one codon.
Priapism
A low - resistance system is formed by resistors added in parallel.

42. What embryonic structure forms the adult male structure? - Corpus cavernosus - corpus spongiosum - and glans and body of the penis
Maxillary division of CN V and glossopharyngeal nerves
Eosin
Phallus
It causes a buildup of dATP - which inhibits ribonucleotide reductase and leads to a decrease in deoxynucleoside triphosphate - a precursor of DNA - resulting in overall bone marrow suppression.

43. What is the most important stimulus for the secretion of insulin?
Frameshift
transcription
An increase in serum glucose levels
Intrinsic factor (IF)

44. If the ratio of a substance's filtrate and plasma concentrations are equal - What is that substance's affect on the kidney?
If the ratio of the filtrate to plasma concentration of a substance is equal - the substance is freely filtered by the kidney.
Filtered and secreted: Cx > Cin (i.e. - PAH). Filtered and reabsorbed: Cx < Cin (i.e. - glucose) - where Cx = clearance of a substance and Cin = clearance of inulin.
Enterokinase
Axis V

45. Name the most common type or cause - Urethritis in a young - newly sexually active individual
Crossover study
Phallus
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.
Staphylococcus saprophyticus

46. When a person goes from supine to standing - what happens to the following? - Dependent venous pressure
Increases Remember - the carotid sinus reflex attempts to compensate by increasing both TPR and heart rate. -------------------------------------------------------------------------------
Wiskott - Aldrich syndrome
Aged adult
ACh; think about the ANS.

47. Name the nephritic disease based on the immunofluorescent staining - Mesangial deposits of IgA and C3
Membranoproliferative glomerulonephritis (MGN)
IgA nephropathy (Berger disease)
Rib 7 articulates with T7 and T8. Each rib articulates with the corresponding numerical vertebral body and the vertebral body below it.
Lateral part of the hemispheres

48. Do not have MHC class I Ags on their surface.
1. Recognize self from nonself 2. Amplify via cell division or complementation 3. Control the level of the response 4. Remove foreign material
RBCs
MEN I (or Wermer syndrome)
Hypoventilation - which increases CO2 - shifting the reaction to the right and increasing H+

49. What family do the following viruses belong to? - Rabies
Dementia Urinary incontinence Gait apraxia (NPH wet - wacky - wobbly)
Posterior interventricular artery
Rhabdovirus
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.

50. What embryonic structure forms the adult male structure? - Ventral part of the penis
Urogenital folds
Fetal alcohol syndrome
Area 6
Lipoprotein lipase