A “source of infection “ is the individual or object from which an infection is actually acquired.
Please correct me if I’m wrong.
HIV? sexual contact, blood, saliva
Heaven or the bad side it depends how are you in your life
I would have to go with (D) sorry if it’s wrong.
The process of heart contraction stimulates by the initiation of an electrical impulse. This electrical impulse starts in the SA node.
<h3>What is the Heart contraction?</h3>
Heart contraction may be defined as a type of physiological activity that stimulates electrical impulses which are initiated by the sinoatrial node. Systole is significantly the contraction phase of the cardiac cycle.
The SA node is a small bundle of specialized cells that is remarkably located in the right atrium. The electrical activity escalates through the walls of the atria and induces them to contract. This action finally forces blood into the ventricles.
Therefore, the SA node is responsible for the initiation of impulses that stimulates heart contraction.
To learn more about Heart contraction, refer to the link:
brainly.com/question/14353904
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