BECOM-2 Exam 2

 


 

  1. Which factors contribute to asthmatic patients’ diminished ability to breathe normally?
    1. Exudate congestion of the lumen space
    2. Smooth muscle constriction, epithelial congestion, and lumen constriction
    3. Permanent enlargement of the bronchioles and lumen constriction
    4. Low systemic pressure causing lumen constriction
    5. Overstimulation of the parasympathetic nervous system


  2. Describe the effects of bronchial pneumonia.
    1. The alveolar lumen is diminished due to smooth muscle cell proliferation.
    2. Pulmonary pressure exceeds systemic pressure over an extended period of time and causes bronchial degradation.
    3. Alveolar cells are destroyed and alveoli increase in size by combining with adjacent alveoli.
    4. Alveolar walls are degraded from the buildup of exudate when neutrophils invade the airway.
    5. Lamellar cells are damaged and surfactant production is diminished, leading to increased elastic pressure.

  3. Which is true regarding the conduction system?
    1. The conduction system begins at the opening of the trachea.
    2. The conduction system begins in the terminal bronchioles.
    3. The conduction system terminates in the respiratory bronchioles.
    4. Gas exchange occurs in the conduction system.
    5. The conduction system begins in the alveolar ducts.

  4. Which would you expect to be elevated in someone with an upper respiratory infection following prolonged secondhand smoke exposure?
    1. Goblet cells
    2. Basal cells
    3. Type II pneumocyte 
    4. Progenitor cells
    5. Small granule cells

  5. Infant respiratory distress syndrome is caused by the lack of production of surfactant in alveoli, which is primarily carried out by which type of cells?
    1. Basal cells
    2. Type II pneumocyte
    3. Progenitor cells
    4. Type I pneumocyte
    5. Goblet cells

  6. An elderly patient in your clinic is being tested for cranial nerve function and is found to have a reduced CN I response. Reduced activity of which respiratory cell type is most likely responsible for this condition?
    1. Brush cells
    2. Small granule cells
    3. Type II pneumocytes
    4. Goblet cells
    5. Pseudostratified ciliated columnar epithelial cells

  7. When taking an HPI for a newly admitted patient with stage 1 lung cancer, you learn that she does not smoke, live with a smoker in the household, or work a job with particularly hazardous levels of airborne debris. What is the most likely diagnosis for this patient?
    1. Large cell carcinoma
    2. Adenocarcinoma
    3. Squamous cell carcinoma
    4. Small-cell carcinoma
    5. Basal cell carcinoma

  8. An expecting mother has been put on the glucocorticosteroid dexamethasone after receiving the news that her child will likely be born with neonatal respiratory distress syndrome. Which of the following respiratory cell types failed to properly develop in the child?
    1. Type I pneumocytes 
    2. Type II pneumocytes
    3. Goblet cells
    4. Brush cells
    5. Basal cells

  9. What condition is characterized by the dilation and enlargement of the bronchioles and alveolar cell loss?
    1. Emphysema
    2. Pulmonary hypertension
    3. Bronchial pneumonia
    4. Asthma
    5. Mesothelioma

  10. In a healthy individual, which of the following is TRUE?
    1. Alveolar VD is zero
    2. Physiological VD = Anatomical VD
    3. Anatomical VD should be close to 150 mL
    4. A & C
    5. A, B & C

  11. Which of the following is TRUE regarding COPD?
    1. Individuals will have increased elastic recoil of their lungs
    2. Individuals will have increased distensibility of their lungs
    3. Individuals will have decreased compliance of their lungs
    4. Individuals will have increased elasticity of their lungs
    5. Individuals will have an increase in lung stiffness

  12. As a 3rd year medical student, your supervising resident tells you to read the slow spirometer readout and present the case the next morning, cautioning you that a pulmonologist will be on rounds and that she loves to trip people up with questions about varying FRC values. The next morning you choose to tell the team that:
    1. FRC is the amount of air a person can breathe at the beginning of a normal expiratory level and distending the lungs to their max amount and that it varies because each person has different size lungs.
    2. FRC is  the amount of air that remains in the lungs at the end of a normal expiration and is dependent on position of the patient and will be at its max when the patient is standing erect.  
    3. FRC is the product of ERV and IRV and varies with the position of the patient and will be at its max when a person is in a reclining position.
    4. FRC is the produce of ERV and RV and varies with the position of the patient and will be at its max when a person is sitting with their arms outstretched.
    5. FRC is an erroneous number, notoriously unreliable and that the resident is trying to trick you and make you look like a fool.


  13. The main force that wants to collapse the lungs is surface tension. This is prevented by the presence of surfactant. How does surfactant change surface tension so that the lungs don’t collapse?
    1. Surfactants from Type I pneumocytes gets between the water molecules and increases the numbers of hydrogen bonds, lowering the surface tension and helping the lungs to stay inflated.
    2. Surfactants from Type II pneumocytes gets between the water molecules that line the alveoli and increases the number of hydrogen bonds, lower the surface tension and helping the lungs to stay inflated.
    3. Surfactants from Type II pneumocytes gets between the water molecules that line the alveoli and decreases the number of hydrogen bonds, lowering the surface tension and helping the lungs to stay inflated.
    4. Surfactants from Type I pneumocytes gets between the water molecules that line the alveoli and decreases the number of hydrogen bonds, raising the surface tension, forcing the walls to stay separated.
    5. Surfactants from Type II pneumocytes get between the water molecules that line the alveoli and decreases the number of hydrogen bonds, raising the surface tension, forcing the walls to stay separated.


  14. You are doing clinical rotations in the Emergency Department when a 45 yo male patient presents with shortness of breath. Fast spirometry is performed, giving you the graph below. Which of the following is true for this patient?
    1. The FEV1/FVC is low, indicating the presence of obstructive lung disease
    2. The FEV1 is low, indicating the presence of obstructive lung disease
    3. The FEV1 is high, indicating the presence of restrictive lung disease
    4. The FEV1/FVC is normal, but the FVC is low indicating restrictive lung disease
    5. This patient is normal


  15. A patient presents with shortness of breath and wheezing. He has a long hx of smoking and you suspect he has Chronic Pulmonary Obstructive Disorder (COPD). Assuming this differential diagnosis is correct, which of the following is NOT true regarding this patient?
    1. COPD is associated with reduced elastic recoil of the lung which causes a reduction in PA (Alveolar Pressure)
    2. The patient’s lung reaches EPP sooner than normal which contributes to their wheezing
    3. This patient will have an increased Functional Residual Capacity (FRC)
    4. This patient will have a increased Vital Capacity (VC)
    5. The FEV1/FVC will be reduced  


  16. You are treating a patient with emphysema that is experiencing shortness of breath and is in respiratory distress. Before administering oxygen to them, you “coach” them to breathe deeply, but slowly. What would be the purpose of doing this?
    1. By encouraging the patient to take slow, deep breathes, you are preventing the trapping of air due to collapse associated with FVC.
    2. The main purpose of this would be to decrease the patient’s anxiety before putting a NR mask on them.
    3. The patient is most likely experiencing respiratory alkalosis from breathing too quickly
    4. This would have no purpose


  17. In a shunt, how would you expect gases in a capillary arriving to the lung to react?
    1. CO2 will remain high and O2 will decrease.
    2. COwill remain low and O2 will remain high.
    3. CO2 will decrease and O2 will increase.
    4. CO2 will remain high and O2 will remain low.
    5. CO2 will increase and O2 remain high.


  18. Calculate the VD from the following values:
             Partial pressure of expired CO2  = 29 mm Hg
             Inspiratory Capacity = 2.9 L 
             Inspiratory Reserve Volume = 2.3 L 
             Partial pressure of arterial CO2  = 40 mm Hg
    1. 200 mL
    2. 138 mL
    3. 145 mL
    4. 150 mL
    5. 165 mL


  19. Diffusing capacity of the lungs (DLCO) can be increased by which of the following conditions?
    1. Polycythemia
    2. Pulmonary edema
    3. Pulmonary fibrosis
    4. Asthma
    5. Emphysema


  20. The rate of gas diffusion would be greater in all EXCEPT which of the following situations?
    1. An increase in membrane surface area
    2. A gas with a higher diffusion coefficient
    3. An increase in partial pressure difference
    4. A decrease in membrane thickness  
    5. A gas with a higher molecular weight


  21. Which of the following has the highest diffusion coefficient?
    1. CO
    2. CO2
    3. O2
    4. N2
    5. He


  22. A patient is taking Acetazolamide, an inhibitor of carbonic anhydrase. What do you expect to see in lab tests?
    1. Decreased CO2 in the plasma
    2. Decreased H+ ions
    3. Increased CO2 levels in the red blood cell
    4. Increased H2CO3 levels in the red blood cell
    5. Decreased hemoglobin concentration in the blood


  23. A 32 year-old patient presents to your ER and is in respiratory distress. He is hyperventilating, but his breaths are very shallow. You run some tests, and the results are as follows:
          pH: 7.31     
          PCO2: 49 mmHg     
          HCO3-: 24 mmHg    
          Lactate: <1.9
    What is your diagnosis for this patient?
    1. Respiratory acidosis
    2. Metabolic acidosis
    3. Respiratory alkalosis
    4. Metabolic alkalosis
    5. Chronic metabolic acidosis


  24. A patient presents with chronic iron deficiency anemia. Her labs show low hemoglobin, low hematocrit, and low iron saturation. In addition to these lab results, what do you expect to see?
    1. Increased SaO2
    2. Unchanged SaO2
    3. Increased PaO2
    4. Decreased PaO2
    5. Unchanged oxygen content


  25. Carboxyhemoglobin formation occurs when an individual encounters low levels of carbon monoxide. Explain why the effects of CO poisoning often go unnoticed without a detector.
    1. Signs of cyanosis go unnoticed due to the individual sleeping.
    2. Partial pressure of O2 is unchanged, so normal signs of hypoxia are not displayed.
    3. Oxygen’s affinity for hemoglobin is decreased, so more oxygen is released to the tissue.
    4. A buildup of CO2 occurs due to the decreased affinity of CO2 by hemoglobin.
    5. Hemoglobin’s affinity for CO2 is greatly increased, resulting in trapping of CO2 in the venous system.


  26. A patient comes into the ER with extreme fatigue and headache, rapid breathing, and an elevated heart rate. During your history taking, you discover that she just came into town to go skiing at the nearby resort, and just arrived from her home in Arkansas this morning. Why should you at least consider treating the patient with the diuretic drug acetazolamide?
    1. The patient is acidotic and acetazolamide aids in the secretion of H+
    2. The patient is acidotic and acetazolamide increases respiratory drive
    3. The patient is alkalotic and acetazolamide inhibits bicarbonate synthesis
    4. The patient is alkalotic and acetazolamide increased respiratory drive
    5. The patient has acute altitude sickness and is not indicated for acetazolamide treatment


  27. A patient arrives to the ER with O2Sat = 74%. The patient is now hyperventilating in an attempt to compensate for his hypoxic state. Which chemoreceptors are the primary controllers of the patient’s compensatory response?
    1. Peripheral O2 chemoreceptors
    2. Peripheral CO2 chemoreceptors
    3. Central O2 chemoreceptors
    4. Central pH chemoreceptors
    5. Central CO2 chemoreceptors


  28. A patient is brought into your ER via EMS. They were found unconscious at home. Upon your examination, you notice the patient is breathing very shallow. A family member reports that they believe the patient has overdosed on their prescription of OxyContin®, an opioid. By which mechanism does opioid overdose affect the respiratory system?
    1. Opioids induce respiratory depression by directly increasing GABA production.
    2. Respiratory depression  is induced via activation of μ-opioid receptors at specific sites in the central nervous system including the pre-Bötzinger complex.
    3. Opioids reduce GABA production leading to decreased contraction of respiratory muscles.
    4. Opioids inhibit central chemoreceptors that release acetylcholine responsible for controlling the respiratory center.
    5. Opioids block the binding site of acetylcholine to receptors leading to the inability to contract respiratory muscles.


  29. COPD is a disease that causes inflammation in the bronchioles, leading to blockage which impedes air flow in and out of the lungs. As a result, patients are unable to rid their body of CO2. The administration of O2 is a common treatment option for patients exhibiting COPD. However, prolonged treatment with oxygen can decrease Hb-CO2 affinity in the blood and cause pCO2 to elevate even further. Which of the following terms best describes this effect?
    1. Bohr Effect
    2. Haldane Effect
    3. Metabolic alkalosis
    4. Respiratory alkalosis
    5. None of the above


  30. Seth is on vacation in the Cayman Islands and decides to go on a nice, relaxing snorkeling excursion. He is trying to dive down deep to look at some cool coral but can’t seem to make it before needing to come back up for air. He tries to “cheat” by hyperventilating before he dives down, but unfortunately passes out before reaching the bottom (don’t worry, he was rescued!). Which of the following best describes what happened?
    1. External pressure caused compression of the carotid artery leading to a decreased blood supply to his precious brain.
    2. Hyperventilation caused a decrease in pCO2 which causes acute respiratory alkalosis and thus Seth’s blackout.
    3. Alveolar pO2 decreased which reduced the transpleural gradient.
    4. Hyperventilation causes Seth’s pCO2 to decrease allowing him to postpone his urgent need to breathe and reach a low enough pO2 to cause a blackout.  
    5. Hyperventilation causes Seth’s pO2 to decrease causing arterial O2  to diffuse back into the alveolus.


  31. You are on a pediatrics rotation when a 8-month female infant presents with recurrent, severe infections, poor growth, and chronic diarrhea. The mother mentions that she had a home birth and that this is the first doctor’s visit her baby has had. You have concerns for an immunodeficiency disease, so you decide to order a flow cytometry which is shown below. You also order TREC/KREC assay. While TREC levels are within normal limits, KREC is low. Based on the results these tests, which of the following would be the best differential diagnosis?
    1. SCID due to deficiency in ADA 
    2. SCID due to deficiency in common gamma chain
    3. SCID due to deficiency in RAG1/RAG2
    4. X-linked agammaglobulinemia
    5. DiGeorge Syndrome


  32. Which of the following is NOT true regarding antigens presenting on the surface of immune cells?
    1. All nucleated cells present MHC I
    2. MHC II is specific to B-cells, Dendritic Cells, and Macrophages
    3. T-cells express CD40 which acts as the receptor for costimulatory cytokines CD80/CD86 from APCs
    4. CD56 is a self-antigen marker for Natural Killer cells
    5. CD19 is expressed on the surface of B-cell


  33. Which of the following is TRUE regarding X-linked SCID?
    1. Individuals with this disease are deficient in common gamma chain, which is a necessary component in interleukins responsible for signaling the formation of T-cells and NKs, but not B-cells.
    2. Individuals with this disease are deficient in RAG-1 and/or RAG-2, which is necessary for the formation of genetically varied receptors on the surface of NKs and T-cells, but not B-cells.
    3. Individuals with this disease will present with low KREC, but normal TREC levels.
    4. Individuals with this disease will have an absence of antibodies due to a deficiency in AID.
    5. Individuals with this disease will lack T-cells, B-cells, and NKs due to a deficiency in ADA.


  34. NKG2D is a transmembrane protein encoded by KLRK1 gene which is located in the NK-gene complex (NKC). In humans, it is expressed by Natural Killer cells and recognizes induced-self proteins which appear on the surface of stressed, malignant transformed, and infected cells. Studies have shown that increased NKG2D can decrease tumor growth and promote survival in patients with lymphoma. Which of the following best describes the role that NKG2D has for NK cells?
    1. NKG2D works as an inhibitory NK receptor
    2. NKG2D dampens NK effector functions
    3. NKG2D is another name for CD56 which is expressed on the surface of NK cells and often used in flow cytometry analysis
    4. NKG2D recognizes MHC I alpha chains
    5. NKG2D works as an activating NK receptor


  35. Which of the following is TRUE regarding MHC II processing?
    1. Antigen Presenting Cells process only exogenous antigens to the surface of MHC II receptors
    2. MHC II processing uses the proteasome-ubiquitin pathway to break down antigens before being presented on the surface of an Antigen Presenting Cell
    3. Immunoproteasome works by increasing the efficiency of the proteasome and, thus, increasing the size of the peptide that will be presented on the surface of MHC II
    4. MHC II processing can sometimes utilize endogenous antigens through a method called cross-presentation
    5. It requires use of TAP, which assists in peptide transportation to the RER for processing


  36. Which of the following would be expressed on a MHC I receptor of a lymphocyte?
    1. LPS on the surface of a gram negative bacteria
    2. Viral proteins expressed by host cell translation
    3. Defective TAP protein
    4. A & B
    5. B & C


  37. Which of the following cell types is the MOST efficient at inducing clonal expansion and proliferation of naive T-cells?
    1. B cells
    2. Macrophages
    3. Dendritic Cells
    4. Plasma Cells
    5. Natural Killer Cells


  38. In which situation would upregulation of HLA-DP, HLA-DQ, and/or HLA-DR occur?
    1. Following the recognition of a PAMP/DAMP by a dendritic cell
    2. Following the recognition of MHC II receptor on an APC by its corresponding T-helper cell
    3. Following the recognition of MHC I receptor on an APC by its corresponding Cytotoxic T-cell
    4. Following the recognition of costimulatory cytokines CD80/86 by CD28 on T-cells
    5. Following the expression of viral proteins by the host cell

  39. A deficiency in which of the following may result in absent or non-functional MHC I molecules?
    1. Invariant chain
    2. Cathepsins
    3. HLA-DQ
    4. β-microglobulin
    5. IFN-γ


  40. Which of the following best explains the purpose of cross-presentation?
    1. Cross-presentation allows the stimulation of T-helper cell immune responses when an antigen presenting cell itself is not infected
    2. Cross-presentation allows the stimulation of cytotoxic immune responses when an antigen presenting cell itself is not infected
    3. Cross-presentation is the process by which the B-cell can present endogenous peptides in MHC I
    4. Cross-presentation is important for eliciting innate cytotoxic effects of Natural Killer cells  
    5. Cross-presentation is a method by which genetic diversity is generated in the BCR and TCR

  41. Penicillin is a group of antibiotics which were among the first medications to be effective against many bacterial infections caused by staphylococci and streptococci. While usually safe, some people report that they are allergic to penicillin. Anaphylaxis results when the host combines the penicillin to a carrier protein, thus, eliciting an inappropriate immune response. In this instance, penicillin is most likely functioning as which of the the following?
    1. Hapten
    2. Immunogen
    3. Adjuvant
    4. Epitope
    5. Toxoid  


  42. Which of the following are preventable by use of conjugate vaccination?
    1. Neisseria meningitidis
    2. Streptococcus pneumoniae
    3. Haemophilus influenzae
    4. A & B
    5. A, B, & C


  43. Which of the following is NOT true regarding BCRs and TCRs?
    1. TCRs recognize epitopes being presented on MHC molecules
    2. BCRs can recognize non-sequential epitopes
    3. TCRs can recognize only non-sequential epitopes
    4. BCRs bind the the antigen directly
    5. BCRs can recognize sequential epitopes


  44. You are on rotations in the Emergency Department when a 26 year old female presents with fever hypotension, vomiting and a rash resembling a sunburn on her palms and soles. Physical exam reveals the patient is undergoing menses and has a tampon inserted into her vagina. You suspect Toxic Shock Syndrome. Which of the following is true concerning TSS?
    1. It is caused by a superantigen that increases the activation of B-cells by binding Fab region on the BCR
    2. It is caused by a superantigen exotoxin that increases the activation of T-cells by binding TCR and MHC II outside of the normal binding site
    3. HIV can cause TSS
    4. S. aureus produces Exotoxin A, leading to TSS
    5. S. pyogenes produces TSST-1, leading to TSS


  45. Which of the following is directly responsible for Signal 1 in the activation of Helper T-cells?
    1. CD3
    2. CD4
    3. CD8
    4. CD79a
    5. CD19
  46. Anergy is a term in immunobiology that describes a lack of reaction by the body’s defense mechanisms to foreign substances. Lymphocytes are said to be anergic when they fail to respond to their specific antigen. Which of the following situations is most likely to result in an anergic lymphocyte?
    1. A B-cell is activated by CD40L
    2. A Cytotoxic T-cell recognizes an epitope on an MHC I receptor being presented by a dendritic cell and upregulated CD28  
    3. A T-helper cell recognizes an MHC II receptor presenting on the surface of a dendritic cell, but has no upregulation of CD28 receptor
    4. A B-cell recognizes a discontinuous epitope on an antigen and presents it in an MHC II receptor while simultaneously upregulating CD40 receptors
    5. None of the above will result in an anergic lymphocyte


  47. Which of the following is the most predominant antibody isotype in internal body fluids?
    1. IgE
    2. IgA
    3. IgD
    4. IgM
    5. IgG


  48. Which of the following can cross mucosal surface, thus will be found in breast milk?
    1. IgA
    2. IgM
    3. IgG
    4. A & B
    5. A & C


  49. Which of the following is BEST at activating the complement?
    1. IgE
    2. IgA
    3. IgM
    4. IgD
    5. IgG


  50. A patient presents to the Emergency Department via ambulance with urticaria, hypotension, wheezing, and shortness of breath. The EMTs report that the patient started experiencing symptoms during his meal at a local restaurant. History reveals a peanut allergy and you suspect anaphylaxis. Which of the following antibodies is most responsible for the immune response associated with anaphylaxis?
    1. IgE
    2. IgA
    3. IgD
    4. IgM
    5. IgG


  51. During replication of a virus some of the viral proteins are expressed on the cell surface membrane of the infected cell. Antibodies can then bind to these viral proteins, inducing the NK cell to release granzymes, which causes the lysis of the infected cell to hinder the spread of the virus. Based on this information, which of the following antibodies is most likely involved in this immune response?
    1. IgE
    2. IgA
    3. IgD
    4. IgG
    5. IgM


  52. Which of the following is NOT involved in providing extensive genetic diversity of the adaptive immune cell receptors via V(D)J Recombination?
    1. RAG 1 & RAG 2
    2. NHEJ
    3. TdT
    4. Exonuclease Activity
    5. AID


  53. You are on an OB-GYN rotation and analyzing the results of some postnatal tests that an infant has recently undergone. The baby’s TREC/KREC assay indicates low TREC & KREC levels. The flow cytometry is shown below. Based on the results these tests, which of the following would be the best differential diagnosis?
    1. SCID due to deficiency in ADA
    2. SCID due to deficiency in common gamma chain
    3. SCID due to deficiency in RAG1/RAG2
    4. X-linked agammaglobulinemia
    5. DiGeorge Syndrome


  54. Which of the following BEST describes isotype exclusion?
    1. Isotype exclusion is the process of silencing a paternal or maternal allele and is particularly important during the formation of the BCR and TCR
    2. Isotype exclusion is the process of silencing a paternal or maternal allele and is particularly important during the formation of MHC II and MHC II
    3. Isotype exclusion is the process of silencing the κ or λ loci on the heavy chain allele during the formation of each BCR
    4. Isotype exclusion is the process of silencing the κ or λ loci on the light chain allele during the formation of each BCR
    5. Isotype exclusion is the process of silencing the κ or λ loci on the heavy chain allele during the formation of each TCR


  55. Which of the following BEST describes somatic hypermutation?
    1. Somatic hypermutation is a process by which T-cells undergo monoclonal expansion to produce TCRs with a higher affinity to antigen
    2. Somatic hypermutation is an antigen specific process in which B-cells are mutated to increase antigen affinity
    3. Somatic hypermutation is a process by which BCRs undergo point mutations in the constant region of the heavy chain to change their effector function
    4. Somatic hypermutation is a process of affinity maturation in which BCRs undergo point mutations in the variable regions to increase antigen affinity
    5. Somatic hypermutation is the process in which AID is utilized to increase TCR affinity to an antigen


  56. You are on an IM rotation when a 2 year old female patient presents with fever cough, tachypnea, lymph node hyperplasia, and cyanosis. You suspect pneumonia and further testing reveals that the patient has been infected with Pneumocystis carinii, an opportunistic microorganism to which individuals with immunodeficiencies are particularly susceptible. An ELISA test reveals an abundance of IgM. A deficiency in which of the following is most likely causing the clinical presentation of this patient?
    1. AID
    2. ADA
    3. TdT
    4. PIgR
    5. Common γc


  57. MHC restriction is a process that occurs following TCR recombination and during T-cell proliferation in the Thymus. Which of the following events would allow for both T-cell proliferation as well as the arrest of beta chain recombination?
    1. Increased prevalence of AID
    2. pre-TCR attachment
    3. Loss of double positive arrangement
    4. Reduction of RAG 1/2
    5. High affinity for MHC II


  58. Not all host protein antigens are present in the thymus. How does negative selection in T cells ensure that they are capable of identifying and binding to proteins only expressed in the periphery?
    1. T cells are not responsible for recognizing these proteins not in the thymus. Macrophages are responsible for identifying and binding to peripheral proteins.
    2. T cells are not able to recognize antigen that is not directly involved in the recombination process.
    3. TdT inserts random nucleotides into sequences to increase variation and enhance identification of peripheral proteins.
    4. RAG 1/2 are responsible for recombination to produce proteins that are almost identical to peripheral proteins.
    5. AIRE is expressed, which is a transcription factor that induces ectopic expression of these host proteins.


  59. If selected by MHC class I, re-expression of CD4 will…
    1. NOT enhance signaling. This weaker signal leads to CD8 commitment.
    2. enhance signaling. This stronger signal leads to CD8 commitment.
    3. NOT enhance signaling. This weaker signal leads to double negative expression.
    4. NOT enhance signaling. This weaker signal leads to CD4 commitment.
    5. enhance signaling. This stronger signal leads to CD4 commitment.


  60. What happens to immature T cells that recognize self MHC and interact strongly with self antigen?
    1. They are removed from the repertoire.
    2. They are selected for recombination.
    3. They lose their selectivity for self MHC and become double negative cells.
    4. They are transported to the thymus for maturation.
    5. They remain in the lymphoid tissue for maturation and then are transported to the thymus.


  61. A 25 year-old female presents to the clinic with fever, chills, and difficulty breathing. You suspect an infection and upon examination of her vitals signs, you note a high fever of 103.6 ºF. Which of the following is TRUE regarding the patient’s fever?
    1. An exogenous pyrogen is contributing to this patient’s fever by directly stimulating prostaglandin E
    2. This patient’s hypothalamic set point is lower compared with a healthy person
    3. Chills are a normal physiologic response that increase body temperature, contributing to her fever
    4. This patient will have a decreased Q10 effect
    5. Endogenous pyrogens are responsible for reducing this patient’s hypothalamic set point


  62. The year is 2030 and Jon has decided to take a luxurious family vacation with his large income as a trauma surgeon. He decides to go to Honolulu, Hawaii which has a similar temperature but a substantially higher percentage of humidity than Jon is acclimated to. The first morning he arrives, he decides to go on a 5 mile beach run, but is found passed out under the hot hawaii sun only a ½ mile up the beach. Which of the following BEST describes Jon’s increased sensitivity to the Hawaii environment?
    1. The hot hawaii sand has caused an increase in conduction, causing Jon to overheat
    2. The high temperature has caused an increase in radiation, causing Jon to overheat
    3. The high humidity has caused an increase in water conduction, causing Jon to overheat
    4. The increased amount of wind in Honolulu has caused and increased amount of convection, allowing Jon to cool more easily
    5. The high humidity has caused a decrease in the ability of Jon’s sweat to evaporate, causing him to overheat.


  63. Which of the following is NOT true regarding an individual who has undergone heat acclimation?
    1. Sweat rate will be increased compared to the unacclimated individual
    2. Sodium reabsorption is decreased compared to the unacclimated individual
    3. Heart rate will be less compared to the unacclimated individual
    4. Rectal Temperature will be less compared to the unacclimated individual
    5. Sweat will be more dilute compared to the unacclimated individual


  64. You are on a pediatrics rotation when a 6 month old female patient presents for a simple check-up. The infant is found to be healthy, however the mother is curious about why her baby, and babies in general, tend to be so chunky. What is is NOT true regarding infants and their ability to thermoregulate?
    1. Babies are unable to shiver
    2. Babies utilize their abundance of yellow fat reserves to increase body temperature
    3. NE stimulates brown fat reserves in infants
    4. Epinephrine stimulates brown fat reserves in infants
    5. Babies cause uncoupling of the proton gradient to increase body temperature


  65. Lie detector tests work on the basis of anxiety sweating. Electrodes are placed on a person of interest, and as one sweats, the electrical conductivity increases across the electrode and the conductivity is recorded. What regulatory mechanism makes lie detector tests possible?
    1. Decreased parasympathetic input on alpha-1 receptors.
    2. Decreased sympathetic input on beta-1 receptors.
    3. Increased sympathetic cholinergic activation of beta-1 receptors
    4. Increased parasympathetic cholinergic activation of beta-2 receptors
    5. Increased sympathetic adrenergic activation of alpha-1 receptors


  66. If kept chilled in preservation solution, a donated heart can remain viable for transplantation for a duration ranging from 3-24 hours (depending on the method of preservation). Which of the following BEST describes the reason for why organs, such as a heart, would be best preserved at lower temperatures?
    1. Lower temperature decreases the Q10 effect, shutting down metabolism and decreasing the rate of tissue death
    2. Lower temperature increases the Q10 effect, shutting down metabolism and decreasing the rate of tissue death
    3. Lower temperature would not be beneficial since excessive cold can damage tissue via ice crystal formation
    4. Lower temperature increases the Q10 effect, increasing the rate of metabolism and decreasing the rate of tissue death
    5. Lower temperature decreases the Q10 effect, increasing the rate of metabolism and decreasing the rate of tissue death


  67. You go outside to play in all the snow that Arkansas got this year (a whopping ½ inch!). You disregarded putting on a jacket because you were only going to go throw a few snowballs at a passersby at The Residents. The wind blows and the hair stands up on your arms. What is causing this response?
    1. A decrease in skin temperature led to stimulation of NTS, resulting in activation of the RVLM and norepinephrine release, leading to piloerection.
    2. The anterior hypothalamus detected a decreasing skin temperature, leading to release of acetylcholine to stimulate the muscarinic receptors, resulting in piloerection.
    3. A decrease in core body temperature lead to stimulation of the posterior hypothalamus, leading to piloerection.
    4. The posterior hypothalamus detected a decrease in skin temperature, leading to release of norepinephrine stimulating alpha-1 receptors, and therefore piloerection.
    5. Peripheral cold receptors activated the sympathetic cholinergic receptors, leading to stimulation of muscarinic receptors, leading to piloerection.


  68. What causes the plateau of stroke volume during incremental exercise?
    1. Redistribution of blood to the skin and increased aortic compliance
    2. Increased blood viscosity due to the loss of water through sweating
    3. Decreased filling time and decreased venous return
    4. Increased preload and increased venous return
    5. Increased end diastolic volume


  69. Emily H., who has a resting heart rate of 72 bpm, has drank the Cross-fit Kool-Aid®. She arrives for a running WOD (workout of the day), and she starts her first round. She goes all out and makes it to the 200 meter mark in 37 seconds. Her heart rate has risen to 96 bpm (I know, right?). What regulatory factor is primarily responsible for her increase in heart rate?
    1. Withdrawal of cardiac vagal tone (parasympathetic stimulation)
    2. Simulation of cardiac sympathetic nervous system activation
    3. Beta-1 receptor stimulation by norepinephrine
    4. Increased influx of Ca2+ into contracting cardiomyocytes
    5. Increased conduction velocity of intrinsic conduction pathways


  70. Venoconstriction by sympathetic stimulation and the muscle pump during exercise contributes to which of the following?
    1. Increased venous return, therefore an increased end diastolic volume
    2. Decreased cardiac output, therefore an increased cardiac output
    3. Decreased aortic compliance, therefore a decreased stroke volume
    4. Increased mean arterial pressure, therefore an increased cardiac output
    5. Increased venous compliance, therefore an increased venous return


  71. Which of the following is NOT true regarding a trained athlete as compared to the untrained individual?
    1. The trained athlete will have a greater Heart Rate Reserve (HRR)
    2. The trained athlete will have a lower max HR at submaximal workload
    3. The trained athlete will have an increase in CO during rest
    4. The trained athlete will have an increase in SV during rest
    5. The trained athlete will have an increase in CO during exercise


  72. Which of the following is advised against in a patient with a compromised cardiac system?
    1. Lower body, isometric exercise
    2. Lower body, low intensity cardiovascular exercise
    3. Upper body, isometric exercise
    4. Whole body, dynamic exercise
    5. Moderate weightlifting


  73. The Valsalva Maneuver is the performance of forced expiration upon a closed mouth and nose. This leads to a results in a dramatic decrease of venous return to the right atrium. What happens during the Valsalva Maneuver
    1. Secondary decrease appears in phase II.
    2. Alleviation of compression and excessive sympathetic stimulation occurs during phase III.
    3. The diaphragm compresses the inferior vena cava.
    4. Post-strain overshoot occurs in phase I.
    5. Reduction in the aortic pulse pressure occurs following Ca2+ influx.

      **Currently undergoing troubleshooting, See answer in comments section below***

  74. Which of the following BEST explains why heart rate tends to increase when exercising in hotter weather, even in the case of short term exercise?
    1. Increased blood flow to the skin causes an increase in CO and, thus, a compensatory increase in HR
    2. Increased blood flow to the skin causes an increase in VO2max, and thus an increase in HR  
    3. Increased sweating causes a decrease in plasma volume and a compensatory increase in HR
    4. Increased blood flow to the skin causes a decrease SV and, thus, a compensatory increase in HR to keep CO constant
    5. Increased sweating causes an increase in central blood volume and a compensatory increase in HR due to the increased CO

      **Currently undergoing troubleshooting, See answer in comments section below***

One thought on “BECOM-2 Exam 2

  1. ehudspeth

    #74 is C
    #75 is D

Leave a Reply

Your email address will not be published.