Heart Conduction System and Vitamin B12

BIOSCIENCE
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Author’s Note:

Answer to the question number 2:
The heart conduction system is made up of a band of specialist cardiac muscle cells
throughout the walls of the heart which transmit signals to the cardiac muscle to contract. The
primary constituents of this heart conduction mechanism are the AV node, SA node, Purkinje
fibers, His bundle, and left and right bundle branches. The SA node begins by triggering the
atrial muscles to contract. The SA node is also known as anatomic pacemaker (van Weerd &
Christoffels, 2016). After that a signal is transmits through the AV node, further through the
bundle of his branches and the ventricles via the Purkinje fibers. This signal generates a current
on a graph called an Electrocardiogram (EKG or ECG) which is visible in the EKG or ECG
machine (Sebastian et al., 2013). The valves among the atria and ventricles are closed when the
atria are void of blood. At that same point the atria commences to recharge and the electrical
signal passes the AV and His bundles to the branches of the Bundle and Purkinje fibers. This
system delivers an instantaneous rhythmic beat in the heart (Sebastian et al., 2013). The activities
in the cardiac process should be harmonized in order to effectively pump the heart and to ensure
the systematic and respiratory circulations operate synchronously.
Impulse generation is the first step in cardiac conduction system. The Sino- Atrial or
SA node contracts and creates nerve signals which travel across the cardiac wall. This leads to
contracts between both atrias. The Sino- Atrial node lies in the right atrium's upper wall. The
nodal tissue has both of nervous and muscle tissue attributes (van Weerd & Christoffels, 2016).
When the Sino- Atrial node pulse reaches the AV node, it takes around ten times fraction of a
second. This pause enables the atria to contract before the ventricle contraction and to
release their contents in the ventricles. The electrical signals are then continued down the atrio-
ventricular bundle. This fiber bundle sections out in to 2 bundles and pulses are traveled in to