true and false -9
The conduction of electric impulses is vital in the functioning of nerves.
T
An electrocardiograph is a device which simulates normal bioelectric potentials when the heart is not capable of producing them.
F
If unliked charges are placed on parallel conducting plates, a current will flow between the plates.
F
Under resting conditions, living cells maintain a voltage about 70 to 90uV between the inside and outside the cell
F
Energy is required from a battery to polarize a capacitor
T
It is active pump mechanisms that distinguish the living cell membrane from a passive nonliving one
T
The voltage pulse produced by the depolarization-repolarization process is referred to as the resting potential
F
Chlorine anions cross membranes only by passive diffusion.
T
The depolarization process is related to conduction of potassium ions into the cell.
F
In axons, an action potential can be generated in one part of the cell and transmitted to other parts
T
The cell membranes in muscle fibers are not capable of producing action potentials
F
The sinoatrial node (SA) is the natural pacemaker of the heart
T
The various components of the ECG pattern are labeled L, Q, R, S, and T
F
The ECG pattern is a valuable diagnostic tool.
T
The transmission of the action potentials in the heart is a vector process, i.e. it is conducted along a preferred direction.
T
The EEG signals cannot be correlated with specific brain activity as accurately as the ECG signals can be related to the heart cycle.
T
The alpha waves are dominant when the patient is in a comatose state
F
the electrical impedance of a biological tissue does not depend upon frequency
F
The pacemaker is implanted subcutaneously in the abdominal region and the leads connect it to the brain.
F
The impedance of a biological tissue depends on frequency.
T
The P wave is associated with the repolarization of AV node and ventricular conduction system.
F
An electrocardiogram records the electrical activity of the heart.
T
The impedance of living tissue contains capacitive and resistive components.
T
The usual standard limb electrodes, the so-called Einthoven leads are placed on the right and left arm and on the right foot.
F
The amplitudes of P, Q, R, S and T waves are measured in uV.
F
The vertical sensitivity of the electrocardiogram can be measured by means of the test signal presented at the beginning of the graph.
T
The larger the capacitance, the more time is required to discharge the capacitor.
T
As the frequency of the electric current increases, the impedance of biological tissues decreases, tending to zero.
T
The hydrophobic core of the plasma membrane is a good electric insulator.
T
The action potential and the resting potential of a neuron can be measured in mV.
T
The strength of impulses carried along a single axon can vary with the strength of the initiating stimulus.
F
A neuron cannot be stimulated during the absolute refractory period.
T