Normally, the rate of the heart beat in a human is determined by _________________?

Related Mcqs:

1. Fastest conducting tissue in human heart _________________?

   A. AV node
   B. SA node
   C. Bundle of His
   D. Purkinje fibers

2. The glomerular filtration rate of the human kidney may be determined by measuring the plasma clearance of______________?

   A. PAH
   B. Urea
   C. Inulin
   D. Glucose

3. Cardiac output in L/min divided by heart rate equals_______________?

   A. Cardiac efficiency
   B. Cardiac index
   C. Mean stroke volume
   D. Mean arterial pressure

4. All of the following causes increase in heart rate except________________?

   A. Halothane
   B. Isoflurane
   C. Sevoflurane
   D. Desflurane

5. One of the obious consequences of alchol ( ethenol), ingestion in many individual is facial flushing and increased heart rate triggered off by alcohol getting metabolized to______________?

   A. Formaldehyde
   B. Acetaldehyde
   C. Propanaldehyde
   D. Butanaldehyde

6. All the heart valves are open during which stage of cardiac cycle __________________?

   A. Systolic ejection
   B. Isovolumetric relaxation
   C. Isovolumetric contraction
   D. None of the above

7. Parasympathetic stimulation of heart causes______________?

   A. SA node decreases firing
   B. Increased AV node excitability
   C. Decreased ventricular contraction
   D. Tachycardia

8. Absolute period when whole heart is in diastole is______________?

   A. 0.7 seconds
   B. 0.3 seconds
   C. 0.7 seconds
   D. 0.4 seconds

9. Heart muscle, true are all except_______________?

   A. Act as syncytium
   B. Has multiple nuclei
   C. Has gap junctions
   D. Has branching

10. 2nd heart sound is characterized by all except______________?

    A. Due to closure of semilunar valves
    B. Is occasionally split
    C. Has longer duration than 1st heart sound
    D. Marks the onset of diastole