BECOM2 EXAM #1
B1: Cardiac Histology
You are on rotations in the Emergency Department with a student from NYIT-Jonesboro. The physician mistakenly asks that student to assist with a pericardiocentesis which is an invasive procedure that involves using a needle and catheter to remove fluid from the pericardium. Unfortunately, the student became distracted and pierces the needle through the heart itself and into the chamber of the left ventricle. In what order (from superficial to deep) would the needle encounter the various layers of the heart?
- Endocardium → Myocardium → Epicardium
- Epicardium → Tunica Media → Endocardium
- Tunica Externa → Tunica Media → Tunica Interna
- Epicardium → Myocardium → Endocardium
- Tunica Interna → Tunica Media → Tunica Externa
Answer D. Lecture #1: Cardiac Histology.
A pathologist is analyzing the sample of muscle shown below. Unfortunately, it has been mislabeled as “skeletal muscle.” But the pathologist knows from experience that this must be cardiac muscle. Which of the following structures is a clear indicator that this micropictograph specimen is indeed cardiac muscle?
- A
- B
- C
- D
- E
Answer A, Intercalated Discs. Lecture #1, Cardiac Histology.
Which of the following is true regarding the differences between atrial myocardium and ventricular myocardium?
- The atrial muscle cells are generally smaller in diameter with less gap junctions
- The ventricular muscle cells are generally smaller in diameter with less gap junctions
- The atrial muscle cells are generally larger in diameter with more gap junctions
- The ventricular muscle cells are generally larger in diameter with less gap junctions
- The ventricular muscle cells conduct impulses at a higher rate
Answer D. Lecture #1: Cardiac Histology.
The DES gene is responsible for encoding Desmin, a protein intermediate filament used in the intercalated discs of the cardiomyocytes. Which of the following would be the most likely clinical presentation of a person with a mutation in this gene?
- The terminal sarcomeres would be unable to connect to Zonula adherens
- The cardiomyocytes would be unable to bind to one another
- Action potentials would be unable to spread between the cardiomyocyte gap junctions
- The cardiomyocytes would be fused together
- Zonula adherens would be non-existent
You are on rotations in the Emergency Department when a patient presents with all the cardinal signs of a myocardial infarction. Which of the following is NOT a potential medication you would consider administering immediately?
- Nitroglycerin
- Morphine
- Lidocaine
- Atropine
- Lisinopril
Answer E. Lisinopril is used to treat HTN and would not be used to treat an MI immediately. Nitroglycerin prevents coronary spasm and reduces myocardial oxygen demand. Morphine relieves pain and anxiety. Lidocaine reduces ventricular arrhythmias/ Atropine restores conduction and increases heart rate. Lecture #1: Cardiac Histology.
You are on rotations in a family med clinic when a 65 year old male patient presents with a pulsatile mass that can be palpated in the upper left quadrant of the abdomen. The patient has been an avid smoker for the last 30 years and has a history of atherosclerosis. Which of the following is the most appropriate differential diagnosis?
- Myocardial Infarction
- Pulmonary Embolism
- Congestive Heart Failure
- Abdominal Aortic Aneurysm
- Pericardial Effusion
Answer D. Lecture #1: Cardiac Histology.
You are practicing venipuncture on your good friend, Lucas T. Upon puncturing his Antecubital Fossa, you notice his blood is bright red and is entering the collection tube in a pulsatile fashion. You must have accidentally punctured an artery! Through which of the following layers (from superficial to deep) would the needle have had to go through in order for this to occur?
- Tunica intima → Tunica Media → Tunica Adventitia
- Tunica Media → Tunica Intima → Tunica Adventitia
- Tunica Adventitia → Tunica Media → Tunica Intima
- Tunica Adventitia → Tunica Intima → Tunica Media
- Tunica Media → Tunica Adventitia → Tunica Intima
Answer C. Lecture #1: Cardiac Histology.
The carotid body is a small cluster of chemoreceptors and supporting cells located near the bifurcation of the carotid artery. These chemoreceptors are sensitive to which of the following?
- Low oxygen content
- High carbon dioxide concentration
- High arterial blood pH
- A & B
- A, B & C
Answer D. The chemoreceptors are sensitive to low oxygen, high CO2, and LOW arterial pH (which makes sense since CO2 is acidic and a high CO2 would cause low pH). Lecture #1: Cardiac Histology.
B2-3: Heart Development I & II
B4: Basic Bacteriology
30 year old IV drug user presents with hot, swollen arm. He has a fever, normal mental state, is breathing 20 bpm, a BP of 136/84 and a HR of 110 bpm. Which of the following best describes his condition?
- Normal
- Simple infection
- Sepsis
- Septic Shock
Answer B. Lecture #4: Basic Bacteriology. Sepsis requires two or more of the following: RR of >22 bpm, altered mental status, SBP of <100 mm Hg.
You are on clinical rotations in the ER when a patient presents with classic “flu-like” symptoms including fever, chills, myalgia, and malaise. The patient had just returned from Liberia two weeks prior and has only just developed symptoms. You are concerned about the possibility of Ebola. Which phase of infectious disease progression is this patient most likely displaying?
- Incubation
- Invasive
- Prodrome
- Acme
- Convalescence
Answer C. Lecture #4: Basic Bacteriology.
Bacterial meningitis is an inflammation of the meninges caused by a bacterial infection. Usually, these infections are due to organisms that have capsules and can, therefore, cross the blood brain barrier. Which of the following is NOT an example of an organism that can cause bacterial meningitis?
- Haemophilus influenzae
- Streptococcus pneumoniae
- Neisseria meningitidis
- Escherichia coli
- Streptococcus pyogenes
Answer E. Streptococcus pyogenes is the only bacteria listed that does not have a capsule.
Which of the following best describes the way in which Penicillin works as an antibiotic?
- Penicillin attacks the teichoic acid in bacterial gram positive cell walls
- Penicillin reduces the toxin effects of IgA protease
- Penicillin inhibits transpeptidase, the enzyme responsible for catalyzing the crosslinks between NAG and NAM in peptidoglycan
- Penicillin works by reducing the toxic effects of LPS in gram negative bacteria
- Penicillin mimics the structure of para-aminobenzoic acid, a compound critical for the synthesis of folic acid
Answer A. Lecture #4: Basic Bacteriology. Sulfa drugs work by the method described in answer E fyi.
What is the physiological response to endotoxin?
- Fever
- Systemic Inflammation
- Diarrhea
- A & B
- A, B, & C
Answer D. Lecture #4: Basic Bacteriology.
Which of the following would be LEAST susceptible to penicillin?
- Obligate aerobe
- Obligate anaerobe
- Spore-forming bacteria
- Gram positive
- Gram negative
Answer E. Lecture #4: Basic Bacteriology. Gram negative would be least susceptible.
- coli is a type of bacteria that can be found normally within your intestines. While infection is possible, most strains of E. coli are considered harmless. Which of the following serves as the best explanation for why this is?
- Only specific strains of E. coli have flagellin
- Only specific strains of E. coli have pili
- Only specific strains of E. coli have lipid A
- Only specific strains of E. coli have tubulin
- Only specific strains of E. coli produce endospores
Answer B. Lecture #4: Basic Bacteriology.
Mannheimia succiniciproducens was a bacterium discovered In 2004. This organism has a unique metabolism involving carbon fixation and grows best in environments with low oxygen and high carbon dioxide. Which of the following terms best describes the metabolic needs of this organism?
- Microaerophile
- Obligate anaerobe
- Aerotolerant anaerobe
- Facultative anaerobe
- Capnophile
Answer E. Lecture #4: Basic Bacteriology.
The year is 2030 and Blue Bell is again under closure for recent outbreaks of food poisoning following the consumption of their ice cream. Which of the following bacteria are most likely to be the culprit?
- Yersinia enterocolitica
- Listeria monocytogenes
- Campylobacter
- A & B
- A, B, & C
Answer D. Lecture #4: Basic Bacteriology.
You are on rotations in a family practice clinic when a patient presents with a suspected bacterial infection. You send a sample of the patient’s septum to the lab to be analyzed. The lab performs a gram stain and a variety of agar cultures. The gram stain is pictured below, however, the lab reports that none of the agar mediums showed any growth after 48 hours. Which of the following bacteria is the most likely culprit?
- Bacillus
- Actinomyces
- Nocardia
- Mycobacteria
- Pseudomonas
Answer B. Lecture #4: Basic Bacteriology. .
B5: Bacterial Toxins
A 25 year-old male presented to a free clinic in the Dominican Republic, complaining of a worsening sore throat, fever, chills, and a loud barking cough. His exa revealed an adherent, thick gray at the back of his throat. What pathogen is most likely causing this patient’s illness?
- Bacillus anthracis
- Bordetella pertussis
- Corynebacterium diphtheriae
- Pseudomonas aeruginosa
- Vibrio cholera
Answer C. Lecture #5: Bacterial toxins.
In regards to the question above: Which of the following bacteria produce a toxin that has a similar mechanism of action?
- Bacillus anthracis
- Bordetella pertussis
- Shigella dysenteriae
- Pseudomonas aeruginosa
- Vibrio cholera
Answer D. Lecture #5: Bacterial toxins.
Which of the following is NOT true regarding Neisseria meningitidis?
- N. meningitidis has LOS in its cell wall, which mimics the effects of LPS.
- N. meningitidis produces IgA protease, which allows it to adhere to mucosal membranes.
- N. meningitidis has a capsule, allowing it to cross the blood brain barrier
- N. meningitidis is an important microorganism to consider in individuals with a splenectomy
- N. meningitidis is a spore forming bacteria
Answer E. Lecture #5: Bacterial toxins.
A 25 year old female presents to the Emergency Department displaying symptoms of shock. She is also exhibiting a high fever, diarrhea, and a sunburn-like rash. Which of the following microorganisms is most likely responsible for her symptoms?
- Staphylococcus aureus
-
- Bordetella pertussis
- Shigella dysenteriae
- Pseudomonas aeruginosa
- Vibrio cholera
Answer A. Lecture #5: Bacterial toxins. This woman is most likely displaying Toxic Shock Syndrome which is due to S. aureus.
A 36 yo male patient presents to the Emergency Department with bloody diarrhea. His primary care physician had prescribed him antibiotics two days prior, but despite this the patient notes worsening symptoms. Upon the completion of blood work, you come to find that this patient is also displaying thrombocytopenia, anemia, and renal dysfunction. Which of the following bacteria is the most likely culprit of this patient’s symptoms?
- Shigella dysenteriae
- Vibrio cholera
- Enterohemorrhagic E. coli
- Enterotoxigenic E. coli
- Bacillus anthracis
Answer C. Lecture #5: Bacterial toxins. This patient is displaying symptoms caused by shiga-like toxin that is produced by EHEC. Bloody diarrhea along with hemolytic uremic syndrome (Thrombocytopenia, anemia, and renal dysfunction) are specific to EHEC and Shigella (dysentariae). However, the fact that antibiotics are not helping suggests that C is a better answer over A.
B6-7: Cardiac Electrophysiology I & II
Zatebradine is an experimental drug designed to inhibit the If current. Which of the following would be consistent with administration of this drug?
- Flatter phase 4 in modal cells; decrease in HR
- Hyperpolarization of nodal cells; increase in HR
- Steeper phase 4 in nodal cells; increase in HR
- Flatter phase 0 in nodal cells; decrease in HR
- Slower phase 3 repolarization in nodal cells; decrease in HR
Answer A. Lecture #5: Bacterial toxins.
B8-9: Basic Mycology & Basic Virology
Amphotericin B, an antifungal drug, targets the sterol in fungi cell membranes binding to it, thus creating a polar pore in fungal membranes. Which of the following does Amphotericin B most likely target?
- Cholesterol
- Ergosterol
- Chitin
- Peptidoglycan
- Sitosterol
Answer B. Lecture #8: Basic Mycology.
Which of the following is the only fungi that has a capsule?
- Candida albicans
- Cryptococcus neoformans
- Aspergillus fumigatus
- Pneumocystis jiroveci
- Klebsiella
Answer B. Lecture #8: Basic Mycology.
You are analyzing a specimen that was gathered from pulmonary abscess on a patient. The microorganism can be seen upon completion of an acid-fast stain. TB is suspected, but you come to find that the patient is negative following additional testing. Which of the following is most likely the culprit for the patient’s pulmonary symptoms?
- Aspergillus fumigatus
- Mycobacterium leprae
- Nocardia asteroides
- Mycobacterium leprae
- Histoplasma capsulatum
Answer C. Lecture #8: Basic Mycology. Nocardia asteroides is a “fungi-like” bacteria that is often mistaken for TB.
B10 &14: ECG I & II
B15-16: Cardiac Cycle I & II
Which one of the following statements about the jugular venous pulse (JVP) is true?
- The height reflects left atrial pressure
- The JVP falls with abdominal compression
- It is best examined with the patient supine
- Large systolic waves are associated with tricuspid regurgitation
- Prominent a waves suggest atrial fibrillation
Answer D. See Dr. Moffitt’s Cardiac Cycle I Handout.
Administration of a muscarinic agonist, such as Pilocarpine, would cause which physiologic response?
- Increased conduction velocity in the SA node
- Increased contractility of the ventricles
- Vasoconstriction
- Increased frequency of depolarization of the SA node
- Slowed conduction through the AV node
Answer E. See Dr. Moffitt’s Cardiac Cycle I Handout.
A 24 year old female patient presents to your ER with chest discomfort and you perform a physical exam. Upon auscultation of the heart, you suspect S2 splitting during exhalation and order an ECG. The ECG shows a prolonged QRS wave. Which of the following would be your diagnosis?
- Left Bundle Branch Block
- Aortic Regurgitation
- Normal physiologic splitting
- Coronary Artery Disease
- Raynaud’s syndrome
Answer: A. See Dr. Moffit’s Cardiac Cycle II Handout. “During inhalation, the pulmonic sound component is delayed as expected, so there may be no detectable split sound. Upon exhalation, the pulmonic valve closes ahead of the aortic valve, since the aortic valve closure and thus aortic component and thus delayed and split sounds may be audible.”
The closure of the A-V valves as a result of the change in A-V pressure gradient that follows atrial contraction and that accompanies ventricular contraction occurs
- Immediately following repolarization
- At the onset of diastasis
- Immediately prior to rapid ejection
- At the onset of isovolumic contraction
- Immediately following isovolumic relaxation
Answer: D. See Dr. Moffit’s Cardiac Cycle I Handout
An increase in systemic blood pressure (or an increase in afterload) would result in
- Increased blood ejection from the right ventricle into the pulmonary artery
- Decreased blood ejection from the left ventricle into the aorta
- Increased blood ejection from the left ventricle into the aorta
- Decreased blood ejection from the right ventricle into the pulmonary artery
- Uneven filling of the right and left atria after rapid ejection
Answer: B. Psys > PLV causes delayed opening of the aortic valve, resulting in less blood being ejected from the heart.
B17: Cardiac Output
B18: Hemodynamics
B19-20: BP Regulation I & II
The picture below shows a diagram of the aortic pulse pressure in a healthy 23 yo female patient. Which of the following is closest to the mean arterial
Pressure?
- 76 mm Hg
- 110 mm Hg
- 60 mm Hg
- 85 mmHg
- 126 mm Hg
Answer A. Lecture #19: BP Regulation I.
SBP = 110 mm Hg
DBP = 60 mm Hg
MAP = DBP + ⅓(Pulse Pressure)
Pulse PRessure = SBP – DBP
MAP = 60 + ⅓(110 – 60) = ~76 mm Hg
Which of the following is true regarding the arterial pulse waveform shown below?
- The red line is associated with arteriolar dilation, increased sympathetic tone and decreased compliance
- The red line is associated with arteriolar constriction, decreased sympathetic tone and decreased compliance
- The red line is associated with arteriolar constriction, increased sympathetic tone and decreased compliance
- The blue line is associated with arteriolar dilation, decreased sympathetic tone and increased compliance
- The blue line is associated with arteriolar constriction, decreased sympathetic tone and decreased compliance
Answer C. Lecture #19: BP Regulation I.
Lucas T. is an 76 yo obese, male patient. He has a hx of HTN that is being controlled with a variety of medications. Currently, Lucas’s BP reads 160/80 mm Hg. Which of the following is true regarding Lucas?
- His blood pressure is not unusual for a man his age as arterial stiffening occurs as patients grow older
- His HTN is associated with an increase in pulse pressure which tends to increase cardiac stress
- His blood pressure is associated with a decrease in compliance
- A & B
- A, B & C
Answer E. Lecture #19: BP Regulation I.
A 25 yo male patient presents to the Emergency Department following a motorcycle accident. The patient had his spinal cord transected at the level of T9, causing paralysis in both legs. The most imminent danger, however, is the patient’s plummeting blood pressure. Which of the following is the most likely reason for his falling blood pressure?
- The patient is likely in an immense amount of pain which stimulates vasodilation to allow for increased blood flow to the area of injury
- The patient is undergoing and increase in parasympathetic stimulation below the level of the transection, causing generalized vasodilation and spinal shock
- The patient is most likely bleeding internally, causing the systemic lowering in blood pressure
- The patient has lost sympathetic stimulation below the level of the transection, causing generalized vasodilation and spinal shock
- The lowering in blood pressure is a response to systemic vasoconstriction which often occurs following acute injury
Answer D. Lecture #19: BP Regulation I.
Carotid sinus hypersensitivity is an exaggerated response to carotid sinus baroreceptor stimulation. It results in dizziness or syncope from transient diminished cerebral perfusion. Which of the following is true regarding the autonomic response to the hypersensitivity of the carotid sinus?
- It would increase the impulses traveling from the vagus nerve to the nucleus solitarius
- It would result in an increased activation of the CVLM, which acts as an inhibitory impulse to the RVLM
- It would result in an increased activation of the CVLM, which directly acts on the heart to cause vasodilation
- It would result in an increased activation of the RVLM, which directly acts on the heart to cause vasodilation
- It would result in an increased activation of the RVLM, which directly acts on the heart to cause vasoconstriction
Answer D. Lecture #20: BP Regulation II.
B21: Capillary Circulation
Cirrhosis is a late stage of scarring of the liver caused by many forms of liver diseases and conditions, such as hepatitis and chronic alcoholism. A common symptom of hepatic cirrhosis is hypoalbuminemia. Which of the following is a likely outcome of hypoalbuminemia caused by hepatic cirrhosis?
- Net hydrostatic pressure will fall on the venous side of the capillary bed, resulting in systemic edema.
- Net oncotic (colloid) pressure will fall on the venous side of the capillary bed, resulting in systemic edema.
- Net hydrostatic pressure will rise on the venous side of the capillary bed, resulting in dehydration.
- Net oncotic (colloid) pressure will rise on the venous side of the capillary bed, resulting in dehydration.
- Net osmotic pressure will be too low for filtration to occur on the arteriole side of the capillary bed.
Answer B. Lecture #21: Capillary Circulation.
B22: Coronary Circulation
Which of the following best explains the reasoning for why aortic regurgitation leads to coronary insufficiency?
- Aortic regurgitation can result in an extremely high systolic blood pressure, which attenuates the pressure gradient between the aorta and coronary arteries during systole and decreases exchange of nutrients
- Aortic regurgitation can result in an extremely low systolic blood pressure, which attenuates the pressure gradient between the aorta and coronary arteries during systole and decreases exchange of nutrients
- Aortic regurgitation can result in an extremely low diastolic blood pressure, which attenuates the pressure gradient between the aorta and coronary arteries during diastole and decreases exchange of nutrients
- Aortic regurgitation can result in an high low diastolic blood pressure, which attenuates the pressure gradient between the aorta and coronary arteries during diastole and decreases exchange of nutrients
- Aortic regurgitation results in decreased cardiac output, which causes a less blood flow to the coronary arteries
Answer C. Lecture #22: Coronary Circulation.
You are on rotations in the Emergency Department when a 35 yo female patient presents with severe tachycardia (260 bpm) following an overdose of Epinephrine. The nurse accidentally administered 5 mL Epi instead of the 0.5 mL that the physician ordered. One of the first things that you are concerned about (besides your rising malpractice insurance) is imminent myocardial infarction. Which of the following best explains why this patient is at a high risk for an MI?
- Severe sympathetic stimulation and tachycardia decrease the time in which diastolic filling occurs, thus decreases the time in which the coronary arteries can fill and feed the heart during diastole.
- Severe sympathetic stimulation and tachycardia increase the time in which diastolic filling occurs, thus decreases the time in which the left coronary arteries can fill and feed the heart during diastole.
- Severe sympathetic stimulation and tachycardia increase the time in which systole occurs, thus increases the coronary pressure leading to cardiac tamponade.
- Severe sympathetic stimulation and tachycardia decrease the time in which systole occurs, thus decreases the ability to of the coronary arteries to fill and feed the heart during systole.
- Severe sympathetic stimulation and tachycardia decrease the time in which systole occurs, thus increases the ability to of the coronary arteries to fill and feed the heart during systole.
Answer A. Lecture #22: Coronary Circulation.
Increased myocardial oxygen demand can be met by:
- An increase in coronary blood flow
- An increase in parasympathetic stimulation
- An increase in oxygen extraction from the cardiac capillaries
- A & B
- A, B, & C
Answer D. Lecture #22: Coronary Circulation. Cardiac tissue is always extracting the max possible oxygen from the capillaries. Therefore, the only way to meet the metabolic demands of the tissue is to increase coronary blood flow. This can be accomplished with sympathetic stimulation, parasympathetic stimulation, physical forces (such as compression or perfusion pressure), or Adenosine.
Coronary artery disease develops when the the coronary arteries become damaged or diseased. Cholesterol-containing deposits (plaque) in your arteries and inflammation are usually to blame for this condition. When plaque builds up, it narrows your coronary arteries, decreasing blood flow to your heart. If a patient were to develop a partial obstruction over time due to this condition, which of the following biological mechanisms might occur in order to compensate?
- No compensation could occur quickly enough; this would result in an infarction
- Collateral anastomoses would develop upstream from the occlusion
- Ventricular hypertrophy would occur due to the increase in coronary pressure
- Adenosine would decrease, causing vasodilation in the coronary arteries
- Left ventricular volume would increase overtime allowing for a higher cardiac output and compensation for the obstruction in the coronary artery
Answer B. Lecture #22: Coronary Circulation. Arteriogenesis would occur, forming an anastomosis between the coronary arteries.
Which of the following is true regarding coronary artery circulation under normal conditions?
- The greatest flow through the right and left coronary arteries is during diastole
- During systole there is very little to no blood flow through the left coronary artery
- During systole there is a significant amount of blood flow through the right coronary artery
- A & B
- A, B & C
Answer E. Lecture #22: Coronary Circulation. See graph below. Most of the filling occurs during diastole in both the R/L coronary arteries. However, there is still significant flow during systole in the R coronary artery.