Because the AV node takes on the role of a very important delay in the cardiac conduction system. Without this delay, the atria and ventricles would contract at the same time.
<h3>Cardiac conduction system</h3>
The conduction system of the heart sends electrical signals, usually generated by the sinus nodes, causing the heart muscle to contract. Pacemaker signals originating from the sinus node travel through the right atrium to the atrioventricular (AV) along the bundle of His and through branches of the bundle, causing myocardial contraction. This signal first stimulates contraction of the right and left atria then flows to the right and left ventricles. That electric current then allows blood to be pumped throughout the body.
Learn more about sequence of travel by an impulse through the cardiac conduction system at brainly.com/question/28269433
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Answer:
The answer is the first option. The trailing edge is composed of many filopodia containing tight parallel bundles. These filopodia push trailing edge away from the location it was previously occupying.
Explanation:
Cells migrating in tissues exhibit both filopodia and lamellipodia. These thin protrusive extensions are ideal for exploring and penetrating tissue spaces. They are also well suited for intercalating between cells, such as during the migration of leukocytes across endothelial layers.
Therefore the answer is the first option.
Through condensation reactions