Biophysics

44)    Chemical shift in the NMR spectra is related to

45)  Indicate the true sentence

46)  To determine images dependent mostly on proton density, the operator needs to set recordings at (abbreviations: TR – repetition time, TE – time to echo)

46)  Choose the correct statement for the neuromuscular junction:

47)  Indicate the phenomena that do not contribute to electrodiffusion:

49)  Which objects within the human’s body have the highest (nearly total) ability to reflect the ultrasound beam:

51)  The infrared light is:

52)  The sound waves:

53)  If the intracellular concentration of a cation is larger than the extracellular one, the Nernst equilibrium potential for this ion is:

54)  During the onset phase of action potential, the bulk electrolyte in the cytoplasm of the axon

55)  At the resting membrane potential of a typical neuronal cell, the values of electrical driving forces for potassium and sodium ions are approximately

56) If the radius of a cylindrical vessel decreases 2 fold then the haemodynamic resistance:

57) Fick’s law states that

58) Detection of signals characterized by a low frequency (tens of Hz) occurs at the basilar membrane:

(answer not sure)

59) Switching off the dark current in the rod takes place due to:

(answer not sure)

60) Ganglion cells innervating the retina beyond the fovea:

61) The Weber-Fechner law states that

62) In the case of the Nernst equilibrium 

64) Indicate the appropriate association:

65) The lens has optic power of -5 dioptres

66) Total optic power of the human eye is approximately:

67) The distance of the object from a thick lens is calculated as:

68) Which of the statements below is correct

69) When the membrane potential is at its resting level

70) Inactivation of sodium channels

71) Which neurotransmitter is released during the neuromuscular transmission

72) Neuromuscular transmission results in:

73) Indicate where are localized the hierarchical pacemakers in the heart (starting from that working with highest frequency):

74) The plateau phase of the action potential generated by a Purkynje cells lasts approximately

75)   Choose the proper association:

76) For the ideal fluid, when the pressure is constant and the diameter of tube is increased 2-fold, the velocity of flow will:

78) In the closed system, when the volume of the system is compressed (a small volume change V), the internal energy will change by (p – pressure, T-temperature, k – Bolzmann constant)

79) The first principle of thermodynamics for ideal gas states that the change of internal energy of a closed system is equal to:

80) When the function of the f channels in the sinoatrial node is increased :

84)     The phenomenom of viscosity is related to:

85)   After action potential generation in the axon:

86)   Viscous resistance (haemodynamic resistance) is defined as:

87)     The intensity of the electrical al field ( E= U/D, U – voltage and D – distance) within the biological membrane is close to:

88)   When the action potential reaches its maximal (peak) value, the membrane potential reaches app. :

89)    When the action potential reaches its minimal value (hyperpolarization), the neural membrane is: