The main responsible for the delay among the atrial and
ventricular contractions is the action potential conduction velocity of the AV
node cells. If the atria and ventricles contract simultaneously, atria cannot
give any help in filling the ventricles, which is needed, especially in those
with stiff ventricles as in the elderly. Hence atria have to contract first and
then the ventricles.
B is the correct answer due to the fact that applied sciences means adding to already developed technology there scientist are creating another drug to cure human diseases by mixing different elements through the process of an experiment
ATP consists of an Adenine base, a ribose (sugar), and 3 phosphate groups
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