What does polarization of the heart mean?
Heart muscle cells are polarized at rest. This means the cells have. slightly unequal concentrations of ions across their cell membranes.
What is depolarization and polarization?
This means that the interior of the cell is negatively charged relative to the outside. Hyperpolarization is when the membrane potential becomes more negative at a particular spot on the neuron’s membrane, while depolarization is when the membrane potential becomes less negative (more positive).
What causes slow repolarization of the heart?
These results are in agreement with the hypothesis that the slow phase of repolarization is due to an inward current generated by Na+-Ca2+ exchange, as latter mechanism is known to be sensitive to the intracellular and extracellular concentrations of both Na+ and Ca2+.
Does depolarization mean relaxation?
When the electrical signal of a depolarization reaches the contractile cells, they contract. When the repolarization signal reaches the myocardial cells, they relax. Thus, the electrical signals cause the mechanical pumping action of the heart.
What is the meaning of depolarization?
1 : the process of depolarizing something or the state of being depolarized. 2 physiology : loss of the difference in charge between the inside and outside of the plasma membrane of a muscle or nerve cell due to a change in permeability and migration of sodium ions to the interior …
What happens to the heart during depolarization?
Depolarization of the heart leads to the contraction of the heart muscles and therefore an EKG is an indirect indicator of heart muscle contraction. The cells of the heart will depolarize without an outside stimulus. This property of cardiac muscle tissue is called automaticity, or autorhythmicity.
How are linear polarization and circular polarization related?
Linear polarization: the electric field of light is confined to a single plane along the direction of propagation (Figure 1) . Circular polarization: the electric field of light consists of two linear components that are perpendicular to each other, equal in amplitude, but have a phase difference of π/2.
How is de polarization related to cardiac sensing?
Interface (de)polarization interferes with cardiac sensing (see Table 11-1 ). In general, interface (de)polarization involving a high polarization charge but a low polarization potential is desirable, which means a high double-layer capacitance C dl.
How is left handedness determined by circular polarization?
When using this convention, left- or right-handedness is determined by pointing one’s left or right thumb away from the source, in the same direction that the wave is propagating, and matching the curling of one’s fingers to the direction of the temporal rotation of the field at a given point in space.
How are the waves oscillate in linear polarization?
In linear polarization, the fields oscillate in a single direction. In circular or elliptical polarization, the fields rotate at a constant rate in a plane as the wave travels. The rotation can have two possible directions; if the fields rotate in a right hand sense with respect to the direction of wave travel,…