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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 embryonic structure forms the adult male structure? - Testes - seminiferous tubules - and rete testes
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.
hCG
C5- C9
Gonads

2. Blue sclera is seen In what hereditary bone disorder?
Osteogenesis imperfecta
They are preganglionic sympathetic axons. They are white because they are myelinated.
Thymine (B1)
The anterior nucleus of the thalamus

3. What is the MCC of death in children aged 1 to 14 in the United States?
Mycosis fungoides (cutaneous T- cell lymphoma)
By causing rebound insomnia and decrease in REM sleep
Accidents
Left abducens nucleus or right cerebral cortex

4. Name the stages of sleep with these EEG patterns: x Delta waves
BPH
Dendrites receive information - whereas axons send information.
Stage 3 and 4
Dissecting aortic aneurysm. MI is also high on the list - but these are buzzwords to look for dissection.

5. What does Candida albicans do that distinguishes it from other fungi?
well - fed and fasting
Swan - neck deformities
VPL nucleus sends its fibers to synapse in the postcentral gyrus of the parietal lobe.
It forms a germinal tube at 37

6. What class of antianginal activates the NO pathway to produce endothelial vasodilation?
hnRNA
overall dopamine activity
Nitrates
Turner syndrome

7. What rate is indicated by 1- sensitivity?
Filovirus
Hypervariable region (three per light chain; three per heavy chain)
False - negative rate
1. a - Ketoglutarate dehydrogenase 2. Pyruvate dehydrogenase 3. Transketolase Thiamine pyrophosphate (TPP) functions as a coenzyme vital to tissue respiration. It is required for the oxidative decarboxylation of pyruvate to form acetyl - coenzyme A -

8. What is the most common one? - Inflammatory arthritis
1. Picornavirus 2. Calicivirus 3. Reovirus (Remember PCR)
naked viruses
Clindamycin
Rheumatoid arthritis

9. What enzyme is essential for the conversion of CO2 to HCO3-?
Middle cerebral artery
Minocycline
Carbonic anhydrase
Fibrillary protein - amyloid protein - and glycosaminoglycans (heparin sulfate mainly)

10. Is an active process due to increased gonadal sex hormones
Gametocytes
Osteosarcoma
In the ventral horn of the spinal cord. UMN cell bodies are in the precentral gyrus of the frontal lobe.
Menstruation

11. Is irreversible
Deferoxamine - penicillamine
Klinefelter syndrome
Ag - Ab binding
The rectouterine pouch (of Douglas)

12. What is the drug of choice - which inhibits oxidative phosphorylation in cestodes - for taeniasis?
Thoracic and sacral
No enzymes are needed. When the stop codon reaches the A site - it results in termination.
Glucose
Niclosamide

13. Name the stages of sleep with these EEG patterns: x Alpha waves
Teratoma (dermoid cyst)
Tropomyosin
Being awake
CN V - VI - VII - and VIII

14. What enzyme catalyzes the rate - limiting step in glycogenolysis?
Glycogen phosphorylase
CSF H+ levels - with acidosis being the main central drive - resulting in hyperventilation (the opposite being true with alkalosis)
Parasympathetic
Hypnozoite

15. What cells of the parathyroid gland are simulated in response to hypocalcemia?
Psoas major
The chief cells of the parathyroid gland release PTH in response to hypocalcemia.
Alcohol and its related problems cost the country approximately $100 billion a year.
Rheumatoid arthritis

16. Orphan Annie cells
Smoking
The inner cortex (paracortex) contains the T cells - so it is considered the thymic - dependent area.
Papillary carcinoma of the ovary
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

17. Name the compartment of the mediastinum associated with the following thoracic structures: Brachiocephalic vein
Medullary carcinoma of the thyroid
Superior
Flumazenil
Hypochondriasis (they will begin with 'I think I have...')

18. What bronchogenic carcinoma is associated with an elevated level of Ca2+ - involves keratin pearls - occurs in men more than women - is associated with smoking - occurs in the major bronchi - and is seen in the central areas of the lung?
Linoleic acid and linolenic acid
Aspiration pneumonia
Squamous cell carcinoma
Paradoxic emboli most commonly enter the arteries through a patent septal defect in the heart.

19. Which integrin mediates adhesion by binding to lymphocyte function - associated Ag 1 (LFA-1) and MAC-1 leukocyte receptors?
They are inversely proportional to each other; as pulse pressure increases - compliance decreases.
Intercellular adhesion molecule (ICAM) 1
The sensory limb is via CN IX - and the motor limb is from CN X.
Type IV hypersensitivity (cell - mediated)

20. What are the three Beta - lactamase inhibitors?
Nystagmus is named by the fast component - Which is the corrective attempt made by the cerebral cortex in response to the initial slow phase.
1. Clavulanic acid 2. Sulbactam 3. Tazobactam
Primitive neuroectodermal tumors (i.e. - medulloblastomas and retinoblastomas)
IgA

21. What is the bioactive form of thyroid hormone?
T3
Uroporphyrinogen III cosynthase
Hyperventilation - which decreases CO2 - shifting the reaction to the left and decreasing H+
Areas 44 and 45

22. What is the term to describe the 5'-3' sequence of one strand being the same as the opposite 5'-3' strand?
Pernicious anemia
Transposons
Agents that decrease ACh function reduce tremors and rigidity - not bradykinesias.
Palindrome

23. What is the term to describe the soft - flabby feel and diminished reflexes seen in patients with acute cerebellar injury to the deep cerebellar nuclei?
Varicella virus and influenza virus
Clostridium tetani
Centriacinar worse in upper lobes; panacinar worse in base of lower lobes
Hypotonia (rag doll appearance)

24. What enzyme catalyzes the reversible oxidative deamination of glutamate and produces the TCA cycle intermediate a - ketoglutarate?
Mesangial macrophages
Glutamate dehydrogenase
Middle cerebral artery
Helicobacter pylori

25. What CN carries preganglionic parasympathetic fibers that innervate the viscera of the neck - thorax - foregut - and midgut?
Malpighian layer (made up of the stratum basale and stratum spinosum)
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.)
Azithromycin
Pasteurella multocida

26. 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.
Streptococcus agalactiae and Escherichia coli
apo B-48
C wave

27. How many pairs of spinal nerves are associated with x Cervical vertebrae?
Eight pairs through seven cervical vertebrae. Totaling 31 pairs of spinal nerves.
Hirschsprung disease
Operon
Physostigmine

28. What is an elevated - fluid - filled cavity between skin layers up to 0.5 cm?
Volvulus
Vesicle (e.g. - poison ivy)
refuse
IL-8 (IL-1 and TNF- gamma also)

29. What leukemia is characterized by Philadelphia chromosomal translocation (9;22); massive splenomegaly; peripheral leukocytosis (commonly > 100 - 00); decreased LAP levels; and nonspecific symptoms of fatigue - malaise - weight loss - and anorexia?
Osteosarcoma
Cryptococcus neoformans
CML
Inspiratory reserve volume (IRV)

30. What subset of adenocarcinoma arises from the terminal bronchioles and/or alveolar walls?
Acid is needed for the activation of pepsin and therefore needed for protein digestion.
Bronchioloalveolar carcinoma
Neuroblastoma
1. CHF 2. Vena caval obstruction or constriction 3. Hepatic cirrhosis 4. Renal artery stenosis

31. Name the primary vesicle the following structures are derived from (proencephalon - mesencephalon - or rhombencephalon) - Cerebral hemispheres
Gain of isotonic fluid (isotonic saline)
3- Phosphoglycerate kinase and pyruvate kinase; this produces two ATPs per enzyme (total four ATPs)
Proencephalon
refractory sexual periods

32. Why is spermatogenesis decreased with anabolic steroid therapy?
Riedel thyroiditis
Exogenous steroids suppress LH release and result in Leydig cell atrophy. Testosterone - produced by Leydig cells - is needed for spermatogenesis.
Poxvirus replicates its DNA in the cytoplasm.
C1 inhibitor (C1- INH)

33. What family do the following viruses belong to? - Rabies
Rhabdovirus
Thalassemia minor
Arginine
70S ribosomes in prokaryotes and 80S ribosomes in eukaryotes

34. What is the most common one? - Bone tumor
Hypnopompic hallucinations occur during awakening - whereas hypnagogic hallucinations occur while one is falling asleep.
They innervate LMNs.
Emphysematous bleb
Metastatic

35. What five cofactors and coenzymes are required by pyruvate dehydrogenase?
Thymidylate synthetase
absorption
5HT1D
1. TTP 2. Lipoic acid 3. Coenzyme A from pantothenate 4. NAD(H) (from niacin or tryptophan) 5. FADH2 (from riboflavin)

36. Which of the following Enterobacteriaceae family members
All are lactose fermenters except Yersinia and Proteus.
1. Cough 2. Coryza 3. Conjunctivitis
Water soluble
Affinity

37. What MAOI does not cause a hypertensive crisis?
Atropine and 2- PAM (pralidoxime)
Selegiline
Enterococcus (Streptococcus faecalis)
Acetazolamide

38. What is the precursor of all sphingolipids?
Ceramide
Squamous cell carcinoma
DNA polymerase - a
Autoimmune hemolytic anemia

39. What axis I disorder is characterized by pronoun reversal - preference for inanimate objects - obliviousness to the external environment - lack of separation anxiety - and abnormalities in language development?
1. Less than 3 cm 2. Clean base 3. Level with the surrounding mucosa
Autism. Head - banging - rocking - and self - injurious behaviors are also common in autism.
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.
Linoleic acid and linolenic acid

40. Name the area of the cerebral cortex with the function described: x Motivation - memory - emotions - violent behaviors - sociosexual behaviors - conditioned responses
Limbic system
S phase
Clozapine
Lateral rectus (CN VI) (LR6 SO4)3

41. What enzyme is blocked by 5- FU?
Microglia
18 years old (except if emancipated)
alpha - Cells; glucagon has stimulatory effects on - cells and inhibitory effects on - cells.
Thymidylate synthetase

42. What is the most abundant neuron in the cerebellum?
Secondary hyperparathyroidism (vitamin D deficiency - renal disease)
Projective test. Most tests with a wide range of possibilities for the answers are projective.
The granule cell. Its neurotransmitter is glutamic acid - Which is also the principal neurotransmitter of the visual pathways.
Flow cytometric analysis

43. How many pairs of spinal nerves exit from the spinal cord?
Gout
Finasteride
Negative reinforcement
31 pairs

44. Name the MCC - Walking pneumonia - seen in teens and military recruits
Molindone
Mycoplasma pneumoniae
Primary hypoaldosteronism (Addison's disease)
Axis III

45. HIV's capsid - core nucleocapsid - and matrix proteins are products of what structural gene?
C- peptide levels
gag gene
The superior mesenteric vein and the splenic vein (after it receives the inferior mesenteric vein) join to form the portal vein.
Liquids - CHO - protein - fat

46. What is the most common one? - Cardiac anomaly in Turner syndrome
Coarctation of the aorta
The placenta
Estrogen
Squamous cell carcinoma

47. Development of what T cell line follows low affinity for self - MHC class II Ags in the thymus?
Autoimmune thrombocytopenia purpura
CD4+T cells
Volvulus
Molluscum contagiosum

48. What part of the heart forms x Posterior wall?
Left atrium
Chromosome 18
Glioblastoma multiforme
GP IIb and IIIa receptors

49. What is the term for a RBC that has a peripheral rim of Hgb with a dark central Hgb - containing area?
Target cell
Body dysmorphic disorder
Hirschsprung disease (aganglionic megacolon)
HTLV-1

50. What is the primary target for the action of glucagon?
Liver (hepatocytes)
Pulmonary infections
Shortens
HBeAb