Damage to the Sinoatrial Node in Humans

Question

Damage to the sinoatrial node in humans
A)is a major contributor to heart attacks.
B)would block conductance between the bundle branches and the Purkinje fibers.
C)would have a negative effect on peripheral resistance.
D)would disrupt the rate and timing of cardiac muscle contractions.
E)would have a direct effect on blood pressure monitors in the aorta.

Accepted Answer

The sinoatrial node (SA node) is responsible for initiating the electrical impulses that regulate the heart rate. Damage to this node would disrupt the rate and timing of cardiac muscle contractions, leading to abnormal heart rhythms and potentially decreased cardiac output. It is not a major contributor to heart attacks, does not block conductance between the bundle branches and the Purkinje fibers, nor does it have a direct effect on blood pressure monitors in the aorta. While changes in peripheral resistance can impact blood pressure, damage to the SA node is not directly related to this.