USMLE Step 1 – Uworld High Yield Notes Complete Test
2022/2023
What are the two major microtubular motor proteins? Which does anterograde axonal transport, which
does retrograde axonal transport? Correct Answer: Kinesin, Dynein
Kinesin: Anterograde
Dynein: Retrograde`
What do you think, immunologically speaking, when you see someone with recurrent Neisseria
infections? Correct Answer: Inability to form the membrane attack (MAC) complex
this is a common complement deficiency
What is the defect in Chronic Granulomatous disease? What is the pathophysiology? Correct Answer:
NADPH Oxidase deficiency leads to the inability to kill intracellular organisms
Characteristic triad of ataxia telangiectasia? Correct Answer: cerebellar ataxia, telangiectasias,
increased risk of sinopulmonary infections
What is the major immune deficiency of ataxia telangiectasia? Correct Answer: IgA deficiency, which
predisposes to infections of the upper and lower airways (and other mucous membranes)
There's a useful mnemonic for Ataxia Telangiectasia and the gene that's mutated. What is it? Correct
Answer: ATM
Ataxia
Telangiectasia
Mutated
ATM gene is responsible for DNA break repair
What is one reason that lead intoxication causes hypochromic anemia? Correct Answer: Mitochondrial
iron transport is important for Heme synthesis! It's inhibited by lead. So you don't make heme in your
mitochondria and you get hypochromic anemia.
What is the biochemical problem in Lesch-Nyhan syndrome? (And, only if you got that right, what are
the really cool symptoms of it?) Correct Answer: Defective purine catabolism, so buildup of purines. It's
an X-linked recessive disorder with mutated HGPRT gene (hypoxanthine-guanine
phosphoribosyltransferase, if you want to impress people).
Now, if you got HGPRT and purine catabolism right, you can say: self-mutilating behavior on top of
mental retardation, choreoathetoid (think Chorea) movements and spasticity.
What is the defect in Niemann-Pick disease?
What causes that?
What is the common macular finding? Correct Answer: Sphingolipid degradation is defective
Caused by an autosomal recessive defect in sphingomyelinase
,Cherry Spot on the macula? Niemann Pick's or Tay Sach's.
If a baby gets exposed to an unclean knife (...) and subsequently develops rigid paralysis, what is the
diagnosis, where do we think this might happen, and how do we prevent it? Correct Answer: Neonatal
Tetanus
Developing Countries
Maternal immunization with tetanus toxoid is the best way to prevent it
an adeuately immunized mom will transfer IgG's across the placenta to the neonate
Which microtubule associated protein aids in anterograde transport of intracellular vesicles and
organelles? Which end of the microtubule do they go towards? Correct Answer: Kinesin.
Towards the (+) rapidly growing end.
What is an early BRAIN finding of Ataxia-Telangiectasia and how does it manifest itself? Correct Answer:
Cerebellar atrophy
manifests as ataxia in the first years of life.
High yield path association for Alzheimer's disease? Correct Answer: Neurofibrillary tangles in the
neocortex
High yield path association for Parkinson's disease? Correct Answer: Loss of neurons in the substantia
nigra
High yield path association for Huntington disease? Correct Answer: Atrophy of caudate nucleus
What are the major manifestations of Ataxia-telangiectasia? Correct Answer: cerebellar ataxia,
oculocutaneous tenlangiectasias, repeated sinopulmonary infections, and an increased incidence of
malignancy
If you heard: amenorrhea, bitemporal hemianopsia, and enlargement of the pituitary gland on brain
imaging, what would you be thinking? Correct Answer: Prolactinoma, the most common pituitary
adenoma.
What embryological layer is the anterior pituitary derived from? Correct Answer: Surface ectoderm
What is the most common congenital abnormality associated with the use of Sodium Valproate during
pregnancy? Correct Answer: neural tube defects, e.g., meningocele
because valproate inhibits intestinal folic acid absorption resulting in teratogenicity
What is the characteristic histology of a craniopharyngioma? Correct Answer: On light microscopy, cysts
are lined by stratified squamous epithelium, possibly with Keratin perals. Cysts are usually filled iwth a
yellow, viscous fluid that's rich in cholesterol crystals.
,Where do craniopharyngyomas arise from? Correct Answer: Craniopharyngiomas are calcified cystic
tumors that arise from remnants of Rathke's pouch (embryonic precuros of the anterior pituitary)
Failure of what process leads due neural tube defects? What can be seen in the amniotic fluid due to
leakage of fetal cebebrospinal fluid? Correct Answer: Failure of fusion of the neuropores.
Alpha-fetoprotein and Acetylcholinesterase may appear in the amniotic fluid
Can a competent patient refuse healthcare? Can a competent patient refuse knowledge of their
potential health situation? Correct Answer: yes and yes
What is the consensus and professional standard regarding the receiving of gifts from patients? Correct
Answer: Don't do it. It's unethical to accept individual gifts from patients, especially of signficant value.
AMA doesn't have clear cut answer, but they recommend careful consideration be used. some general
guidelines:
-cash gifts should never be accepted (this includes gift certificates)
-a gift should never influence treatment
-no specific dollar value is given; but as a rule of thumb, it shouldn't be above patient's or physician's
means
-psychiatrist must be super careful even with small gifts
-maintain consistency among all patients
-if physician would be embarrassed or uncomfortable if his colleagues found out about the gift, don't
accept it
Is displacement a mature or immature defense mechanism? What is displacement? Correct Answer:
Immature. A patient redirects emotions from the person or object that's causing the emotions (e.g.,
wife), but who it woudl be completely unacceptable to direct those emotions toward, to a more
acceptable, but still inappropriate, person or object (e.g., a wall or a vase).
Is sublimation a mature or immature defense mechanism? How does it work? Correct Answer: Mature.
Unacceptable drives are redirected toward completely acceptable targets. (Workout hard if you're
angry)
Is projection a mature or immature defense mechanism? What is it? Correct Answer: Immature.
Unacceptable or personally disagreeable impulses are attributed to others; e.g., a student who wants to
cheat on a test accuses his classmates of cheating. Or the gayness thing
Is reaction formation immature or mature defense mechanism? what is it? Correct Answer: immature,
where unacceptable feeligns are IGNORED and the opposite sentiment is adopted (forced). man who's
mad at his wife instead compliments her dress
Is splitting a mature or immature defense mechanism? what is it? Correct Answer: immature. frequently
employed by patients with borderline personality disorder, everything is either "good or bad."
What do you do if you suspect child abuse? Ask the parents or call child protective services? Correct
Answer: Call Child Protective Services immediately!
, Psychologically speaking, what phenomenon is "white coat syndrome" associated with? Correct Answer:
Classical Conditioning. In classical conditioning, a reflexive response normally elicited by an
unconditioned stimulus becomes evocable by a second, formally neutral (conditioned) stimulus.
What three things can patients with bulimia develop (hint: one isn't weight loss because bulimia doesn't
work.)? Correct Answer: (1) bilateral partodi gland enlargement
(2) erosion of tooth enamel*
(3) irregular menses
What is the pulmonary capillary wedge pressure and what does it indirectly measure? Correct Answer:
Pressure in the pulmonary artey distal to the point of its occlusion by an inflated intravascular balloon.
Since there's no significant blood flow towards the left atrium (LA) beyong this point of occlusion, the
pressure at the tip of the "wedged" pulmonary artery catheter is an indirect measurement of LA
Pressure.
What would we expect, in a normal patient, the relationship to be between LA and LV pressure during
diastole? Correct Answer: We would expect them to be nearly equale (both <12) since the open mitral
valve offers minimal resistance to flow between the 2 chambers
What is the characteristic finding via cardiac catheterization in a patient with mitral valve stenosis? I.e.,
if we see what value elevated while the other remains normal, when do we think "Mitral Valve
Stenosis." Correct Answer: Cardiac Catheterization will reveal a LA end diastolic pressure (via pulmonary
capillary wedge pressure) that is significantly greater than the LV end diastolic pressure (LVEDP).
This abnormal pressure gradient implies increased resistance to flow between the LA and LV, i.e., mitral
valve stenosis.
Summarize the key points of pulmonary capillary wedge pressures (PCWP) and how it helps us diagnose
mitral valve stenosis. Correct Answer: The Pulmonary capillary wedge pressure (PCWP) measures
LAEDP. Under normal conditions, the LAEDP is nearly equal to the LVEDP. Mitral stenosis eleveates the
LAEDP and PCWP relative to the LVEDP.
Generally speaking, regarding blood flow through our vessels, the law of conservation of mass states
that the total flow of mass into a contained system must be equal to the total outflow of mass from that
system in a steady state.
What equation helps us prove the following condition: to maintain a constant fluid flow througha tube
with varying diametes, how are cross-sectional area and flow velocities related? Correct Answer:
Volume in must equal volume out, right? Vol(in) = A1 * V1 ; Vol(out) = A2*V2
So any rearrangement of that equation holds true in a physiological system.
A2 = A1*V1 / V2 for example, works.
This applies for blood flow in the cardiovascular system.
2022/2023
What are the two major microtubular motor proteins? Which does anterograde axonal transport, which
does retrograde axonal transport? Correct Answer: Kinesin, Dynein
Kinesin: Anterograde
Dynein: Retrograde`
What do you think, immunologically speaking, when you see someone with recurrent Neisseria
infections? Correct Answer: Inability to form the membrane attack (MAC) complex
this is a common complement deficiency
What is the defect in Chronic Granulomatous disease? What is the pathophysiology? Correct Answer:
NADPH Oxidase deficiency leads to the inability to kill intracellular organisms
Characteristic triad of ataxia telangiectasia? Correct Answer: cerebellar ataxia, telangiectasias,
increased risk of sinopulmonary infections
What is the major immune deficiency of ataxia telangiectasia? Correct Answer: IgA deficiency, which
predisposes to infections of the upper and lower airways (and other mucous membranes)
There's a useful mnemonic for Ataxia Telangiectasia and the gene that's mutated. What is it? Correct
Answer: ATM
Ataxia
Telangiectasia
Mutated
ATM gene is responsible for DNA break repair
What is one reason that lead intoxication causes hypochromic anemia? Correct Answer: Mitochondrial
iron transport is important for Heme synthesis! It's inhibited by lead. So you don't make heme in your
mitochondria and you get hypochromic anemia.
What is the biochemical problem in Lesch-Nyhan syndrome? (And, only if you got that right, what are
the really cool symptoms of it?) Correct Answer: Defective purine catabolism, so buildup of purines. It's
an X-linked recessive disorder with mutated HGPRT gene (hypoxanthine-guanine
phosphoribosyltransferase, if you want to impress people).
Now, if you got HGPRT and purine catabolism right, you can say: self-mutilating behavior on top of
mental retardation, choreoathetoid (think Chorea) movements and spasticity.
What is the defect in Niemann-Pick disease?
What causes that?
What is the common macular finding? Correct Answer: Sphingolipid degradation is defective
Caused by an autosomal recessive defect in sphingomyelinase
,Cherry Spot on the macula? Niemann Pick's or Tay Sach's.
If a baby gets exposed to an unclean knife (...) and subsequently develops rigid paralysis, what is the
diagnosis, where do we think this might happen, and how do we prevent it? Correct Answer: Neonatal
Tetanus
Developing Countries
Maternal immunization with tetanus toxoid is the best way to prevent it
an adeuately immunized mom will transfer IgG's across the placenta to the neonate
Which microtubule associated protein aids in anterograde transport of intracellular vesicles and
organelles? Which end of the microtubule do they go towards? Correct Answer: Kinesin.
Towards the (+) rapidly growing end.
What is an early BRAIN finding of Ataxia-Telangiectasia and how does it manifest itself? Correct Answer:
Cerebellar atrophy
manifests as ataxia in the first years of life.
High yield path association for Alzheimer's disease? Correct Answer: Neurofibrillary tangles in the
neocortex
High yield path association for Parkinson's disease? Correct Answer: Loss of neurons in the substantia
nigra
High yield path association for Huntington disease? Correct Answer: Atrophy of caudate nucleus
What are the major manifestations of Ataxia-telangiectasia? Correct Answer: cerebellar ataxia,
oculocutaneous tenlangiectasias, repeated sinopulmonary infections, and an increased incidence of
malignancy
If you heard: amenorrhea, bitemporal hemianopsia, and enlargement of the pituitary gland on brain
imaging, what would you be thinking? Correct Answer: Prolactinoma, the most common pituitary
adenoma.
What embryological layer is the anterior pituitary derived from? Correct Answer: Surface ectoderm
What is the most common congenital abnormality associated with the use of Sodium Valproate during
pregnancy? Correct Answer: neural tube defects, e.g., meningocele
because valproate inhibits intestinal folic acid absorption resulting in teratogenicity
What is the characteristic histology of a craniopharyngioma? Correct Answer: On light microscopy, cysts
are lined by stratified squamous epithelium, possibly with Keratin perals. Cysts are usually filled iwth a
yellow, viscous fluid that's rich in cholesterol crystals.
,Where do craniopharyngyomas arise from? Correct Answer: Craniopharyngiomas are calcified cystic
tumors that arise from remnants of Rathke's pouch (embryonic precuros of the anterior pituitary)
Failure of what process leads due neural tube defects? What can be seen in the amniotic fluid due to
leakage of fetal cebebrospinal fluid? Correct Answer: Failure of fusion of the neuropores.
Alpha-fetoprotein and Acetylcholinesterase may appear in the amniotic fluid
Can a competent patient refuse healthcare? Can a competent patient refuse knowledge of their
potential health situation? Correct Answer: yes and yes
What is the consensus and professional standard regarding the receiving of gifts from patients? Correct
Answer: Don't do it. It's unethical to accept individual gifts from patients, especially of signficant value.
AMA doesn't have clear cut answer, but they recommend careful consideration be used. some general
guidelines:
-cash gifts should never be accepted (this includes gift certificates)
-a gift should never influence treatment
-no specific dollar value is given; but as a rule of thumb, it shouldn't be above patient's or physician's
means
-psychiatrist must be super careful even with small gifts
-maintain consistency among all patients
-if physician would be embarrassed or uncomfortable if his colleagues found out about the gift, don't
accept it
Is displacement a mature or immature defense mechanism? What is displacement? Correct Answer:
Immature. A patient redirects emotions from the person or object that's causing the emotions (e.g.,
wife), but who it woudl be completely unacceptable to direct those emotions toward, to a more
acceptable, but still inappropriate, person or object (e.g., a wall or a vase).
Is sublimation a mature or immature defense mechanism? How does it work? Correct Answer: Mature.
Unacceptable drives are redirected toward completely acceptable targets. (Workout hard if you're
angry)
Is projection a mature or immature defense mechanism? What is it? Correct Answer: Immature.
Unacceptable or personally disagreeable impulses are attributed to others; e.g., a student who wants to
cheat on a test accuses his classmates of cheating. Or the gayness thing
Is reaction formation immature or mature defense mechanism? what is it? Correct Answer: immature,
where unacceptable feeligns are IGNORED and the opposite sentiment is adopted (forced). man who's
mad at his wife instead compliments her dress
Is splitting a mature or immature defense mechanism? what is it? Correct Answer: immature. frequently
employed by patients with borderline personality disorder, everything is either "good or bad."
What do you do if you suspect child abuse? Ask the parents or call child protective services? Correct
Answer: Call Child Protective Services immediately!
, Psychologically speaking, what phenomenon is "white coat syndrome" associated with? Correct Answer:
Classical Conditioning. In classical conditioning, a reflexive response normally elicited by an
unconditioned stimulus becomes evocable by a second, formally neutral (conditioned) stimulus.
What three things can patients with bulimia develop (hint: one isn't weight loss because bulimia doesn't
work.)? Correct Answer: (1) bilateral partodi gland enlargement
(2) erosion of tooth enamel*
(3) irregular menses
What is the pulmonary capillary wedge pressure and what does it indirectly measure? Correct Answer:
Pressure in the pulmonary artey distal to the point of its occlusion by an inflated intravascular balloon.
Since there's no significant blood flow towards the left atrium (LA) beyong this point of occlusion, the
pressure at the tip of the "wedged" pulmonary artery catheter is an indirect measurement of LA
Pressure.
What would we expect, in a normal patient, the relationship to be between LA and LV pressure during
diastole? Correct Answer: We would expect them to be nearly equale (both <12) since the open mitral
valve offers minimal resistance to flow between the 2 chambers
What is the characteristic finding via cardiac catheterization in a patient with mitral valve stenosis? I.e.,
if we see what value elevated while the other remains normal, when do we think "Mitral Valve
Stenosis." Correct Answer: Cardiac Catheterization will reveal a LA end diastolic pressure (via pulmonary
capillary wedge pressure) that is significantly greater than the LV end diastolic pressure (LVEDP).
This abnormal pressure gradient implies increased resistance to flow between the LA and LV, i.e., mitral
valve stenosis.
Summarize the key points of pulmonary capillary wedge pressures (PCWP) and how it helps us diagnose
mitral valve stenosis. Correct Answer: The Pulmonary capillary wedge pressure (PCWP) measures
LAEDP. Under normal conditions, the LAEDP is nearly equal to the LVEDP. Mitral stenosis eleveates the
LAEDP and PCWP relative to the LVEDP.
Generally speaking, regarding blood flow through our vessels, the law of conservation of mass states
that the total flow of mass into a contained system must be equal to the total outflow of mass from that
system in a steady state.
What equation helps us prove the following condition: to maintain a constant fluid flow througha tube
with varying diametes, how are cross-sectional area and flow velocities related? Correct Answer:
Volume in must equal volume out, right? Vol(in) = A1 * V1 ; Vol(out) = A2*V2
So any rearrangement of that equation holds true in a physiological system.
A2 = A1*V1 / V2 for example, works.
This applies for blood flow in the cardiovascular system.
