ANATOMY
LIMB VASCULATURE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
true
|
|
|
false
|
|
|
Either A or B
|
|
|
None of the above
|
Detailed explanation-1: -The AV node slightly slows the neural impulse from the SA node, which causes a delay between depolarization of the atria and the ventricles. The normal firing rate in the AV node is lower than that of the SA node because it slows the rate of neural impulses.
Detailed explanation-2: -The atrioventricular node delays the SA node’s electrical signal. It delays the signal by a consistent amount of time (a fraction of a second) each time. The delay ensures that your atria are empty of blood before the contraction stops.
Detailed explanation-3: -The SA node starts the sequence by causing the atrial muscles to contract. That’s why doctors sometimes call it the anatomical pacemaker. Next, the signal travels to the AV node, through the bundle of HIS, down the bundle branches, and through the Purkinje fibers, causing the ventricles to contract.