أسئلة فسيولوجي MCQ - بنك اسئلة فسيولوجي RES
أسئلة فسيولوجي Respiratory system MCQ مجمعة ومنقحة بالإجابات الصحيحة وتشتمل على جزء CVS في الفسيولوجيوتضمن المقالة عدد ضخم من اسئلة فسيولوجي في جزء Respiratory system MCQ
يمكن مذاكرتها واعتبارها أسئلة فسيولوجي صيدلة أو أسئلة فسيولوجي تمريض وليس فقط أسئلة فسيولوجي لكلية الطب البشري وحدها فقط
1.Which is the most common organism causing community acquired pneumonia?
b) hemophilus influenzi
d) gm negatives
2.which organism causing pneumonia has an increased association with COPD
b) hemophilus influenzi
d) gm negatives
3.Which organism causing pneumonia has an increased incidence in IV drug users
and those post-influenza?
b) staph aureus
d) gm negatives
4.Which drug/s should be used in adult mild-mod. Community acquired pneumonia?
d) any of the above as a single drug
e) amoxycillin and rulide
5.Which drug regimen is suggested for severe community acquired pneumonia
a) benzyl penicillin and gentamicin and erythromycin
b) benzyl penicillin and gentamicin
c) ceftriaxone and gentamicin
d) gentamicin and erythromycin
e) flucloxacillin and gentamicin
6.Which bug makes up 50% of hospital acquired pneumonia?
b) staph aureus
c) gm –ve bacilli
e) chlamydia psittici
7.What is the largest size spontaneous primary pneumothorax that can be managaed
without aspiration or thoracostomy?
8.In which sort of pneumoathorax is aspiration likely to be most successful?
e) equally effective in all of the above
9.What if the role of aspiration in traumatic pneumothoraces?
a) there is no role
b) first line management in small pneumathoraces only
c) it should be tried in all pneumathoraces as long as there is no respiratory
d) it can be repeated twice before thoracostomy tube is considered
e) none of the above
10.Whatis the recurrence rate of primary spontaneous pneumathoraces?
11.Which is not a biochemical feature of transudative pleural effusions?
b) pleural protein:serum protein <0.5
c) pleural LDH : seurm LDH < 0.6
d) pleural glucose< serum glucose
e) none of the above are biochemical features
12.Which of the list below is not the cause of an exudative pleural effusion?
a) viral pneumonia
e) Nephrotic syndrome
13.Which of the list below is not a cause of a transudative pleural effusion?
e) Nephritic syndrome
14.Which is not a possible cause of haemoptysis?
b) Mitral stenosis
d) Aortic stenosis
15.Which statement is false about haemoptysis?
a) massive haemoptysis is greater than 600ml in 24 hours
b) a CXR is normal in about 25 % of cases
c) in any four cases, one is likely to be due to nonteuberculous infection, one due
to neoplasia, one due to rarer causes and one idiopathic
d) in massive hemoptysis the pt should be nursed bleeding lung up
e) if possible a double lumen tube should be reserved for post brochoscopy as a
rigid bronchoscope cannot be passed down it
16.Which drug/intervention is of no proven benefit in management of acute severe
asthma in adults?
17.As a generalization, at what PEFR should someone be admitted?
a) PEFR<25% pretreatment and <40% posttreatment
b) PEFR<10% pretreatment and <20% posttreatment
c) PEFR<40% pretreatment and <60% posttreatment
d) PEFR<50% pretreatment and <70% posttreatment
e) PEFR is of no value in this decision
18.Which statement is false?
a) Ipratropium is of definite proven benefit in asthma when used with B agonists
b) Ketamine is the intubation agent of choise but in ongoing therapy in acute
asthma no benefit has yet been proven in the few studies done
c) Oral steroids are as effective as parenteral steroids
d) Aminophylline may have a role in acute treatment in children but not in adults
e) No studies have been done to see whether adrenaine is better than parenteral
19.Which is FALSE regarding CPAP in acute asthma?
a) it decreases the work of breathing
b) it causes bronchodilation and decreases airway resistance
c) it improves gas exchange if used alone in severe asthma
d) it may be an effective alternative to ETT when maximal pharmacotherapy is
e) it reduces the cardiovascular impact of changes in pressures caused by asthma
20.Which drug/intervention is rarely used acutely in the acute setting of exacerbation
21.Which statement is incorrect regarding the acute management of exacerbation of
a) support for the widespread use of steroids is limited
b) support for the use of salbutamol combined with ipratropium is limited
c) B agonists are widely used assuming the possiblility of a small reversible
component to the airflow obstruction
d) Support for the widespread use of CPAP and BiPAP is minimal
e) Theophylline is rarely used acutely
22.Regarding pulmonary emboli, which statement is correct?
a) a normal Aa gradient excludes a PE
b) a paO2>80 excludes a PE
c) a normal CXR excludes a PE
d) anticoagulation reduces mortality from PE from 30% to 10%
e) all of the above are correct
23.With regards to PE which statement is CORRECT?
a) embolectomy has a better outcome than thrombolysis in massive PE
b) streptokinase is more effective with lower side effects than tPA in massive PE
c) LMWH is probably as effective as unfractionated heparin
d) TOE is sensitive for peripheral emboli
e) Spiral CT angiography is better at detecting peripheral clots than central
1)A 2)B 3)B 4)D 5)A 6)C
7)C 8)C 9)A 10)E 11)D 12)E
13)C 14)D 15)D 16)E 17)A 18)A
19)C 20)C 21)D 22)D 23)C
1. Which is true regarding community acquired pneumonia?
a. Use of high dose penicillin in penicillin resistant Strep pneumoniae is
rarely successful in treating the pneumonia.
b. Mycoplasma pneumoniae is more commonly seen in elderly patients.
c. Leigonella spp pneumonia is usually moderately severe and can cause
pancreatitis, and myocarditis.
d. H. influenzae is more commonly seen in young, otherwise well
e. Klebsiella pneumoniae is an aerobic gram positive bacillus.
2. Which statement regarding pneumonia in INCORRECT?
a. In patients with AIDS once the CD4 count reaches 800 they are at high
risk of PCP.
b. Mild PCP can be treated with oral cotrimoxazole for 21 days.
c. Transplant patients are most at risk of opportunistic infections between
days 30 and 120 post transplant.
d. Gram –ve organism’s account for 50% of all hospital acquired
e. Only 40% of patients who aspirate will develop pneumonia.
3. Which is INCORRECT regarding lung abscess?
a. 90% of patients will have evidence of periodontal disease or some
predisposition to aspiration.
b. Staph aureus is the most common cause.
c. Sputum examination is often unhelpful in identifying the organism
d. Medical management with antibiotics for up to 2 months is the
treatment of choice.
e. Non infectious causes of lung abscess include rheumatoid nodules and
4. A patient with pneumonia develops a pleural effusion, which you aspirate.
Which of the following is supportive of an empyema on examining the fluid?
a. Pleural protein <30g/l
b. Pleural glucose: plasma glucose > 1.0
c. Pleural LDH : serum LDH ratio < 0.6
d. pH 7.15
e. RBC > 100,000 mm3.
1=C 2=A 3=B 4=D
5. Which of the following is incorrect regarding pneumothorax?
a. 70% of patients with pneumothorax are smokers.
b. Catamenial pneumothorax may occur probably secondary to
endometrial metastases to lungs.
c. Oxygen treatment will increase rate of pleural air resorption 4 times
and should be given to all patients with pneumothorax.
d. A patient with calculated average interpleural distance of 1cm can be
e. The recurrence rate of pneumothorax is approx 15% with half of those
occurring in the first year.
6. A 50 year old male presents with haemoptysis of approx 700 mls over 24
hours. Which is true regarding this man?
a. The bleeding is most likely secondary to pulmonary vessels.
b. The preferred position for this patient is with the affected lung up.
c. Placement of an ETT will prevent possible contamination of the good
lung with blood.
d. Placement of a Robertshaw ETT will protect the good lung and allow
passing of a fiberoptic bronchoscope.
e. Bronchial artery embolization has an 80% chance of stopping the
7. Regarding treatment of asthma in adults which is the correct answer.
a. Intravenous hydrocortisone will have faster onset of anti-inflammatory
action than oral prednisolone.
b. Nebulized ipatropium bromide in combination with salbutamol has
been shown to have a better clinical outcome than salbutamol used
c. It has been shown that IV aminophylline use in severe asthmatics with
optimal beta agonist and corticosteroid therapy will confer benefit.
d. Magnesium has been shown in severe asthma to reduce admission rates
and improve FEV1.
e. Long acting beta agonist have been shown to be beneficial in acute
exacerbations of asthma.
8. Which is true of COAD?
a. 100 % of patients with homozygous alpha-1 antitrypsin deficancy
patients will exhibit evidence of emphysema eventually.
b. “pink puffers have predominantly chronic bronchitis.
c. Use of longterm inhaled steroids has been shown to decrease morbidity.
d. Use of CPAP in acute exacerbations will improve gas exchange.
e. All of above are incorrect.
5=E 6=E 7=D 8=E
9. Which is not true of lung transplant patients.
a. Early rejection may present as cough, chest tightness and decline in
FEV1 by greater than10%.
b. Lung transplant patients do not require prophylaxis for endocarditis.
c. Post transplant lymphoproliferative disease is usually fatal is occurring
greater than one year post transplant.
d. Obliterative bronchiolitis is the most common cause of death 2 years
plus after transplant.
e. CMV infection will usually cause neutropenia..
10. What is the overall probability of PE in a patient with a normal V:Q scan ?
e. none of the above.
11. Which is incorrect regarding acute respiratory distress syndrome?
a. Reduced compliance of lungs due to increased collagen and fibroblast
activity is an early stage of ARDS.
b. Severe hypoxaemia despite normal or low PaC02 occurs early.
c. ARDS usually develops 12-72 hrs post triggering event.
d. Mechanical ventilation can sometimes worsen oxygen delivary to
tissues secondary to reduced cardiac output.
e. Inhalational nitric oxide has been used in the treatment but is at present
experimental due to unknown long term effects and clinical relevance
12. which is not a recognized sign on lateral neck xray of adult epiglottitis?
a. Blunted swollen epiglottis
b. Supraglottic haze
c. Prevertebral swelling
d. Swelling aryepiglottic folds
e. All of the above.
9=B 10=B 11=A 12=E
1. Which of the following is most correct about respiratory infections in patients
a. CMV is a common cause of clinically significant disease
b. CAP pneumonias are more common than PCP in patients with HIV
c. PCP occurs when the CD4 count is between 800 and 1000
d. Mortality from bacterial pneumonia is higher in patients with HIV than
in patients who are HIV-negative
e. Pulmonary aspergillosis is not a life threatening illness.
2. With regard to aspiration pneumonia, which of the following is incorrect?
a. The right lower lobe is the commonest area for aspiration in the erect
b. pH less than 2.0 is associated with a higher mortality
c. Many of the symptoms of aspiration are due to the body’s
inflammatory response to the infectious or irritative material.
d. Streptococcus species are the commonest infecting organism
e. All patients who aspirate should be commenced on broad spectrum
3. In patients with Tuberculosis, which of the following is incorrect?
a. Aerosolised saliva and sputum are the commonest modes of
b. Interferon 8 levels increase in patients who are responding to treatment.
c. Pulmonary TB is an AIDS-defining illness.
d. Extra-pulmonary manifestations are unlikely in HIV patients.
e. Initial therapy is with isoniazid, rifampicin, ethambutol and
pyrazinamide for 2 months.
4. In spontaneous pneumothorax, which is incorrect?
a. 95% will have pleuritic chest pain on the side of the pneumothorax
b. Only 5% with be tachypnoeic or tachycardic
c. Spontaneous pneumothoraces of 35% deflation can be managed
d. CT scan is the current “gold standard” for measuring deflation
e. Spontaneous pneumothorax in HIV patients suggests PCP infection
and carries a high mortality
1 B 2 E 3 D 4 C
23Which of the following is LEAST likely to cause upper lobe pulmonary fibrosis?
e) Ankylosing Spondylitis
38A patient has known small cell bronchogenic carcinoma. He has no other medical
history, and is on no medications. He presents with a serum Na of 126 (measured by
ion sensitive electrode), and is clinically euvolaemic. Investigations will also reveal:
f) Normal serum osmolarity
g) Urine osmolarity less than plasma osmolarity
h) Urinary Na less than 10mmol/L
i) Low serum thyroxine
j) None of the above
43An adult with severe asthma has been intubated. Mechanical ventilation should:
k) Deliver high minute volumes
l) Be set at a high inspiratory flow rate
m) Be adjusted to maintain a normal PaCO2
n) Employ a high PEEP
o) Have a short expiratory time (TE)
20 Regarding COPD which is correct
A >50% is caused by smoking
B. 10% is caused by alpha-1- antitrypsin deficiency
C. may be related to childhood respiratory illnesses
23. Massive haemoptysis is an occasional complication of
a) aortic stenosis
b) aortic incompetence
c) mitral stenosis
d) mitral incompetence
e) right sided valve lesions
c [rosen ch.78, tintin p379] from rupture of pulmonary bronchial venous connection
24. Clubbing is commonly associated with all but which of the following?
d) congenital heart dis
e) idiopathic pulmonary fibrosis
c [dunn p 803, T+O’C p34] other common causes: IE, lung abscess, ca lung
25. Pleural exudates are characterised by
a) protein > 50% serum
b) LDH > 60% serum
c) cholesterol > 30% serum
d) pleural fluid cholesterol >1.5 mmol/L
e) all of the above
e [dunn p806] Light’s criteria
26. Regarding lung volumes which is true
a) Total Lung Capacity = Vital Capacity + Tidal Volume
b) Inspiratory Reserve = TV + Residual Volume
c) Tidal Volume = 1L in 70kg male
d) Vital Capacity = 5L in 70 kg male
e) none of the above
d [dunn p769]
27. Common causes of lower lobe pulmonary fibrosis include
c) coalminer’s lung
d) allergic alveolitis
the rest are upper lobe + aspergillosis, sarcoid, ank spon
38. Which of the following indicates severe asthma?
a) Pulsus paradoxus < 20 mmHg
b) Pulsus paradoxus < 10 mmHg
c) Pulsus paradoxus > 20 mmHg
d) Pulsus paradoxus > 10 mmHg
e) Pulsus paradoxus < 30 mmHg
Pulsus paradoxus is an accentuation of the decrease in systolic blood pressure that normally
occurs during inspiration. A drop in blood pressure of greater than 20 mm Hg (i.e., pulsus
paradoxus > 20 mm Hg) indicates excessive negative intrathoracic pressure and correlates
with severe asthma. In this situation, left ventricular after load and venous return to the right
heart are increased, thereby causing a transient reduction in cardiac output and systolic blood
58. What is the best position in which to place patient with massive haemoptysis?
a) Affected side up
b) Affected side down
d) Reverse Trendelenburg
e) None of the above
Tint chap 63
60. The following can cause a rise in peak inspiratory pressure (PIP) in a mechanically
ventilated patient EXCEPT:
a) insufficient muscle paralysis
b) increased tidal volume
e) increased I:E ratio
9Severe Asthma is indicated by all of the following except
a. Pt talking in words
b. Silent chest
c. PCO2 44mmHg
d. PO2 89mmHg
e. Pulsus paradoxus
47All of the following may have a role in the acute management of severe asthma
50Symptoms heralding respiratory arrest during an asthma exacerbation
include all of the following EXCEPT
G. severe respiratory alkalosis and the use of accessory muscles of
H. a normal pCO2 on arterial blood gas
I. a silent chest on auscultation
51Complications of Mycoplasma pneumonia infection include all of the
K. Guillain-Barré syndrome
L. aseptic meningitis and encephalitis
M. haemolytic anaemia
N. pericarditis and myocarditis
O. septic arthritis
52Which of the following is the BEST view to request when assessing for the
presence of pneumothorax on chest x-ray?
P. Supine anteroposterior
Q. Upright posteroanterior (PA)
R. Inspiratory PA
S. Lateral decubitus with the patient lying on the unaffected side
T. Expiratory PA
a) CRX: hyperinflation
b) Bronchodilators are controversial
c) WBC usually normal
d) Steroids contraindicated
CXR: hyperinflation without infiltrates, peribronchial cuffing, atelectasis
Steroids possible beneficial for mild to moderate, definitely not contra-indicated
Adrenaline most effective therapy
Bronchodilators may help, are controversial
WCC doesn’t help assessment
1. A 43 year old man is receiving positive pressure ventilation on a
respirator following a road traffic crash. His ABG shows a pH
7.54, PC02 28mmHg, P02 87mmHg, Bic 16 mmol/L.
This blood gas shows:
a) pure respiratory alkalosis
b) respiratory alkalosis and hypoxaemia
c) respiratory alkalosis and metabolic acidosis
d) mixed respiratory and metabolic alkalosis
e) metabolic alkalosis with partial respiratory compensation
6. Uncuffed endotracheal tubes should be used for:
a) tube sizes less than 6mm
b) acute epiglottis
c) blind nasotracheal intubation
d) intubations with a Macintosh blade
e) known fractured base of skull
7. Cricoid pressure was first described by:
9. All of the following drugs can be used in rapid sequence induction
47. In asthma:
a) the white blood cell count will often be elevated
b) the ECG may show signs of acute left heart strain
c) a CXR should be routine in all patients admitted
d) blood gas results correlate well with pulmonary function testing
e) theophylline dosing needs to be increased if erythromycin is given
49. Regarding pleural effusion all of the following are true
a) can be tapped to make a diagnosis of pancreatitis
b) can be detected radiographically when 10 ml of fluid is present
c) is most commonly caused by congestive cardiac failure
d) can result from rheumatoid arthritis
e) will not produce mediastinal shift
50. Sore throat is caused by all of the following
a) neisseria gonorrheae
b) mycoplasma pneumoniae
c) bacteroides fragilis
e) corynebacterium diptheriae
51. Regarding empiric antibiotic therapy in pneumonia:
a) cetazidime is used for atypical pneumonia
b) clindamycin is used for aspiration pneumonia
c) acyclovir is used for post influenza pneumonia
d) erythromycin is used for PCP pneumonia
e) amoxycillin alone is used for neonates with pneumonia
86. The patient with normal lungs and pulmonary gas exchange
breathing 40% oxygen at sea level and breathing normally could be
expected to achieve an arterial oxygen tension of about:
a) 180 mm Hg
b) 210 mm Hg
c) 235 mm Hg
d) 260 mm Hg
e) 290 mm Hg
11) Regarding aspiration pneumonitis which is true
a. Should be treated with high dose IV steroids
b. Commonest organisms involved in community acquired are anaerobes and
a. Should be treated with high dose steroids. Can’t find evidence for this
b. *Commonest organisms are GNB and anaerobes. Staph aureus also common
in mouth but more so in aspirated saliva than vomit
55) Which of the following is true of COPD
a. Associated with decreased compliance
b. Associated with low output cardiac failure
c. Associated with reduced FVC but normal FEV1
55) Which of the following is true of COPD
a. Associated with decreased compliance – false....increased compliance
b. *Associated with low output CCF. Pulmonary HPT with RV hypertrophy and
then dilation with cor pulmonale (LVF) and low LV output
c. Associated with decreased FVC but normal FEV1. both reduced FEV1 > FVC
1- Which of the following is NOT a function of the lungs?
b- Serves as a reservoir of blood from the Rt atrium.
c- It is a filter to protect the systemic vasculature
d- Facilitates the exchange of O2 and CO2 between air and blood
Answer: b, the lungs receive blood from Right ventricle not Right atrium
2- Gas exchanging occurs firstly at
a- Terminal bronchioles
b- Respiratory bronchioles
c- Segmental bronchi
Answer: b, the respiratory bronchioles contain some alveoli
3- In air flow obstruction the FEV1/FVC
a- Same as normal
b- More than normal
c- less than normal
Answer: c, the FEV1 decreases to a great extent in obstructive lung disease
4- During inspiration all are true except
a- The rips move upwards
b- The diaphragm lifts up
c- The anterio-posterior dimension of the chest is increased
d- The transverse dimension of the thorax is increased
Answer: b, the diaphragm moves downwards during inspiration to decrease the
intrathoracic pressure which helps the air to move in.
5- During inspiration
a- Alveolar pressure is less than atmospheric
b- Alveolar pressure is greater than atmospheric
c- Alveolar pressure is the same as atmospheric
d- Alveolar pressure is 1mmHg
Answer : a, alveolar pressure becomes lower than the atmospheric during inspiration so the
air flows in.
6- In Hb-O2 association curve, which is false?
a- Increase P50 means O2 binds less tightly to Hb
b- Increase in PCO2 shifts it to the right
c- Increase 2,3-DPG shifts it to the left
d- Decrease in PH increases PCO2
Answer: c, increase 2,3-DPG shifts the curve to the right not to the left
7- CO2 can be transported in the blood
a- As bicarbonate
b- Dissolved in the blood
c- Bound to the amino end groups in proteins
d- All of the above
Answer: d, it can be in all forms mentioned above
8- Which of the following is the primary regulating variable of the central
c- Arterial pH
d- A,B and C
Answer: a, the only gas that can excite the central chemoreceptors is CO2 by increasing H+
in the brain fluids
9- Regarding the peripheral chemoreceptors, which respond is true?
a- Respond to a rise in PaO2
b- Respond to a fall in PaCO2
c- Respond to respiratory alkalemia
d- Are in the carotid and aortic bodies
Answer: d, the peripheral chemoreceptors are located in the aortic and carotid bodies.
10- If dead space is one third of the tidal volume and arterial PCO2 is 45mmHg, the mixed
expired PCO2 is
Answer : c, Expired PCO2 = (TV-DS) arterial (alveolar) PCO2 / TV
11- In pulmonary embolism
a- Ventilation/perfusion ratio infinite number
b- The PaO2 would be greater than normal
c- The PaCO2 would be 0
d- All of the above
Answer: a, the V/P ratio will not be altered because both ventilation and perfusion will
not be affected
12- Concerning the ventilation and perfusion of different regions of the lung?
a- Alveoli at the top of the lung are better ventilated
b- The Hb moving through the base of the lung is less saturated than that at the apex of the
c- Ventilation/perfusion ratio at the apex of the lung is better than at the base of the lung
d- All of the above
Answer: d, ventilation at the apex of the lungs is better, Hb at the base is less saturated
because V/P ratio is less at the base of the lungs
13- The expired volume of air after taking maximum inspiration and expiring maximally
a- Vital capacity
b- Residual volume
c- Total lung capacity
d- Forced expiratory volume at first second
14- Central chemoreceptors
a- Part of CSF
b- Respond to increase in CSF pH
c- Respond to decrease in PaO2
d- Located in medullary respiratory center
15- For surfactant, which is true?
a- Decreases the surface tension of the alveolar fluid
b- Increase the compliance of the lung
c- Is produced by type II pneumocytes
d- All of the above
16- The Hering-Breuer reflexes orginate from the:
a- Chemoreceptors in the lungs
c- Carotid and aortic lungs
d- Mechanoreceptors in the lungs
Answer: D, the Hering-breuer reflexes are affected by the inflation and deflation
receptors in the lungs.
17- In ascending to high altitudes a person is likely to develop
a- a fall in arterial pH
b- a rise in arterial PaCO2
c- a fall in arterial PaO2
d- a decrease in red blood cells count
Answer: c, because inhalation becomes harder in high altitudes (low atmospheric
18- the inspiratory center
a- is situated in the midbrain
b- sends out regular impulses to the inspiratory muscles during quiet respiration
c- sends out regular impulses to the expiratory muscles during quiet respiration
d- is stimulated by swallowing and vomiting
Answer: b, inspiration is an active process which needs the movements of the muscles
19- the lungs do not normally collapse because of
b- intrapleural pressure
c- elastic recoil
d- both a and b
Answer: d, both surfactant and intrapleural pressure prevent the lung from collapsing by
increasing the compliance of lungs
20- the rate of diffusion of a gas across the pulmonary membrane increases as the
a- pulmonary membrane becomes thicker
b- surface area of the pulmonary membrane decreases
c- partial pressure gradient of the gas across the pulmonary membrane increases
d- diffusion coefficient of the gas decreases
Answer: c, the rate of diffusion is directly proportional to the pressure gradient.
21- the partial pressure of the carbon dioxide in the venous blood is
a- greater than in the tissue space
b- less than in the tissue space
c- less than in the alveoli
d- less than in the arterial blood
Answer: b, the PaCO2 is less in tissues due to the diffusion of CO2 to the venous blood in
order to be excreted.
22- the oxygen-hemoglobin dissociation curve is adaptive because it
a- shifts to the right in the pulmonary capillaries and to the left in the tissue capillaries
b- shifts to the left in the pulmonary capillaries and to the right in the tissue capillaries
c- Linear shape
d- Does not shift
Answer: b, the affinity of hemoglobin to oxygen is higher in the pulmonary capillaries that
is why it shifts to the left.
23- Metabolic functions of the lung include all of the following EXCEPT?
a- Synthesis of surfactant
b- Synthesis of prostaglandins
c- Inactivation of bradycinin
d- Inactivation of angiotensin II
24- When CO2 diffuses into blood in systemic capillaries most of it
a- Remains in solution as CO2
b- Converts to carbamino compounds
c- Converts to bicarbonate ions in RBCs
d- Combines with Hb directly
Answer: c, 90% of the total amount of CO2 in the arterial blood is present in HCO3 form
in plasma and RBCs.
25- Peripheral and central chemoreceptors may both contribute to the increased
ventilation that occurs as a result of
a- A decrease in arterial oxygen content
b- A decrease in arterial blood pressure
c- An increase in arterial PaCO2
d-An increase in arterial pH
Answer: c, increase in the PaCO2 is the only stimulus of central and peripheral
26- the pulmonary blood flow at the lung apices
a- less than at bases
b- more than at their bases
c- the same of their bases
d- not effect by gravity
Answer: a, due to the effect of gravity.
27- 2,3DPG (2,3 diphosphoglycerate) is present in high
concentration in RBCs is:
a- combines with hemoglobin to force it to release O2
b- help RBCs to binding with O2
c- maintain the O2 inside RBCs
d- no thing from above
28- The surface tension of the alveolar fluid:
a- increases the lung compliance.
b- decreases the lung compliance.
d- no effect in lung compliance .
29- Decrease in blood PH leads to :
a- stimulation of the respiratory center by stimulating the peripheral chemoreceptor
b- stimulation of the respiratory center by stimulating the central chemoreceptor
c- inhibition of respiratory center by inhibiting the peripheral chemoreceptor
d- inhibition of respiratory center by inhibiting the central chemoreceptor
Answer: a, peripheral chemoreceptors are sensitive to the increase in H ions in the blood.
30- Being in high altitudes leads to:.
a- rapid breathing
b- slow breathing
d- normal breathing
31- hering brewer reflexes play important role during:
a- eupnea in adult
d- sleep & anesthesia
32- Bronchodilitation is the effect of increased activity of:
a- non-adrenergic non-cholinergic effect.
b- parasympathetic nerve system.
c- enteric nerve system.
d- sympathetic nerve system.
33- Involuntary breathing is caused by the:
c- Cerebral cortex
d- Pons and Medulla oblongata
Answer: d, because it contains the Respiratory centers
34- Carbon monoxide is dangerous because:
a- It binds strongly to hemoglobin, making it unavailable to oxygen
b- It binds strongly to plasma, making it unavailable to carbon dioxide
c- It raises the blood’s pH level, causing a person to hyperventilate
d- Carbon monoxide is not harmful, we have it in our bodies normally.
Answer: a, the affinity of CO to Hb is higher than that of O2
35- The exchange of gases between the blood within the capillaries and tissue fluid
surrounding the body's cells is called?
a- external respiration
b- cell metabolism
c- cellular respiration
d- internal respiration
36- About how many alveoli are there in the lungs?
a- 300 million b- 300 billion
c- 300 trillion c- none of the above
37- Which of these is a protective reflex?
38- Reduce affinity of hemoglobin to O2
a- is known as the haldan’s effect
b- favors uptake of O2 at the lung
c- can be caused by increased plasma (H+)
d- is signified by reduced P50
39- Bronchodilatation is likely produced by:
a- cholinergic muscarinic agonists
b- ß2 adrenergic antagonists
c- ß2 adrenergic agonists
40- The peripheral chemoreceptors:
a- are activated only by hypoxia
b- quickly adapt to hypoxia
c- are the major site through which CO2 stimulate ventilation
d- are stimulated both by hypoxic and stagnant hypoxias
a- is produced by type 1 alveolar epithelial cells
b- increases lung compliance
c- is a glycoprotein
d- production starts only after delivery of term babies
42- In quite breathing expiration is:
a- passive and due to elastic lung tissue alone
b- passive and both to surface tension and elastic tissue
c- active due intercostals muscles
d- accompanied by an increase in the recoil force of the lung
a- is caused by low hemoglobin concentration
b- is caused by high concentration of carboxyhemoglobin
c- may be caused by hypoxic or stagnant hypoxia
d- its occurrence is related to the proportion and not the absolute concentration of reduced
Answer: c, it is caused by the abnormally great increase of reduced Hb, it appears in
patients with hypoxic or stagnant hypoxia.
44- The rhythemicity center:
a- is located in the pons
b- is spontaneously active
c- activity causes expiration
d- activity is increased by pneumotaxic center
45- Hypoventiation may lead to:
a- low PCO2 in venous blood
b- high PCO2 in arterial blood
c- low ionized serum calcium
d- shift of the hemoglobin oxygen dissociation to the left
Answer: b, hypoventilation causes hypercapnia and that means CO2 would increase in the
46- The vital capacity:
a- is higher in the elderly than young adults
b- more than 80% of it expired in the first second of forced expiration
c- is twice as much in females than in males
d- is increased by surfactant deficiency
47- Pulmonary fibrosis would be expected to produce:
a- histotoxic hypoxia
b- stagnant hypoxia
c- decreased vital capacity
d- increased compliance
Answer: c, because fibrosis will decrease the elasticity of the lungs which will decrease the
48- Which of the following has the greatest effect on the capacity of blood to transport
a- hemoglobin concentration
b- pH of plasma
c- PCO2 of blood
d- Temperature of the blood
49-The physiological dead space:
a- Is exactly equal to the anatomic dead space in normal people
b-Increases during exercise
c- Is measured by single breath nitrogen analysis
d-Is higher in elderly than young adults
50-A veno-arterial shunt is likely to:
a- Decrease the cardiac output
b- Increase the pulse pressure
c- Increase venous return
d- Decrease PaO2
Answer: d, because there are bronchial veins, which drain their blood directly to the
pulmonary veins and some coronary veins drain their blood to the left side of the heart
51- In a patient, hypoventilation is most likely if:
a- PaO2 is low
b- pH of arterial blood is low
c- PaCO2 is high
d- O2 in arterial blood is low
Answer: c, in hypoventilation, the CO2 accumulate in the blood and not excreted well
through the lungs.
52- Exchange of which of the following gases across the respiratory membrane is
normally diffusion limited:
b- Carbon dioxide
c- Carbon monoxide
Answer: c, Carbon monoxide cannot move freely across the alveo-capillary membrane.