Purkinje fibres Purkinje fibres were first described by a Czech physiologist, Jan Evangelista Purkinje in 1839, noting that they had a different structure compared to the reverseing muscle. They are work myocardial fibres, which extend from the Bundle of His to the inner ventricular walls, bounteous beneath the endocardium. Rows of Purkinje cells are connected to make up independently Purkinje fibre, which run along the septum of the heart, separating the estimable and left ventricles. Their main unscramble is to distribute the action potentials originating in the pacemaker to the ventricular cardiac muscle cells causing the ventricles to contract, rather than actually producing the contractile force. They emergence away action potentials approximately eight times winged than modal(a) cardiac cells. During the cardiac cycle, an electrical impulse is created at the sinoatrial lymph secretory organ (SAN), located in the right atrium, under the influence of the freeh earted branch of the autonomic nervous system. This impulse is propagated across the atria to weary them to contract simultaneously (atrial systole) and is represented on an electrocardiogram (ECG) as the P wave. Next, the impulse travels to the atrioventricular node (AV node), located contact by the atria and ventricles.
Once the impulse vexes the AV node, it is delayed in that location onward being conducted through the fast conduction interlocking of the bunch together of His (located in the septum), down the left and right bundle branches and in conclusion arriving at the Purkinje fibres to the myocardi um of the ventricles. The time interpreted f! or an impulse from the SA node to reach the Purkinje fibres is represented as the P-R interval on the ECG. This enables the ventricles to contract (ventricular systole) from the bill to the base of the heart in a coordinated mood and allow the blood to go by the ventricles via the aorta and pulmonary artery, which is represented as the QRS complex on an ECG. The T wave of an ECG represents ventricular diastole i.e. the...If you want to get a full essay, order it on our website: OrderCustomPaper.com
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