Explain how heart contraction triggered
Explain how heart contraction triggered?
Expert
Heart contraction is independent from neuronal stimulus (although it can be modulated by autonomous nervous system). In heart, there are pacemaker cells which trigger by themselves the action potentials which start the muscle contraction. Such cells are concentrated at two special points of the heart: the sinoatrial node (that is, SA node) positioned in the superior part of the right atrium and the atrioventricular node (that is, AV node) positioned near the interatrial septum.
The action potentials produced by depolarization of the SA node cells propagate cell to cell all through the atria generating the atrial contraction. The atrial depolarization as well propagates to the AV node which then transmits the electric impulse to the ventricles via specialized conduction bundles of the interventricular septum (that is, the bundle of His) and then to the Purkinje fibers of the ventricle walls causing the ventricular contraction. (Atrial contraction leads the ventricular contraction for blood to fill the ventricles prior to the ventricular contraction.)The re-polarization of the SA node forms the atria relax and then the ventricles relax as well.
How do antibody-based tests detect how HIV disease works?
Name the chemical substances which compose the plasma membrane?
Why is it a strong evolutionary hypothesis which, though viruses are the structurally simplest beings they were not the initial living beings?
what is the ph inside the stomach? why is the need to keep that PH level?
Explain the term binder? Answer: The binding protein (generally antibody) that binds to the ligand is termed as binder.
In accordance with the stimuli they accumulate, how the sensory receptors are classified?
Project Manager: Responsible for Planning, Execution and Closure of any project. Here the project is defined by the characteristic of being temporary strive, having unique objective with defined beginning and end and constrained by time and/or financi
Which vessels carry the blood to the kidneys? Whether this blood venous or arterial?
How different are endosperm of gymnosperms and the endosperm of angiosperms?
Two models of color TV sets designated Alpha and Beta are produced by Allison Company. The profit on Alpha is $300 and the profit on Beta is $250. There are 40 hours of labor each day in the production department and 45 hours of machine time available each day. The co
18,76,764
1948532 Asked
3,689
Active Tutors
1422058
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!