Answer:
The correct answer will be option A.
Explanation:
The electrical impulses are generated in the sino-atrial node or SA node, a mass of cells which generates impulse in the upper atrium.
This electrical impulse transmits from the sino-atrial node to the atrio-ventricular node in the lower portion of the upper atrium through the internodal pathway- the pathway composed of atrial cells.
Once the impulse reaches the AV node, it is transferred to the ventricular portion of the heart through Bundle of His presence in the ventricular septum. This bundle of his divides into left and right ventricles through bundle branches and stimulates both the ventricles.
Thus, option-A is the correct answer.
That would be the independent variable :)
Answer:
Organisms decompose more quickly when they are in contact with oxygen. ... When an organism is buried quickly, there is less decay and the better the chance for it to be preserved. The hard parts of organisms, such as bones, shells, and teeth have a better chance of becoming fossils than do softer parts.
Explanation: