With the advent of technology, researchers have been able to focus their attention on the messengers of the brain, neurotransmitters. researchers can introduce to alter the activity level of a neurotransmitter in order to analyze the effects that are opposite of those usually produced by that neurotransmitter.

Are the earth's ocean floor and continents the same age geologically? why or why not?

What is the problem in this article? what solution does the article propose?

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.