Seems weird for psych but I will try..
Explain why, at every level, our existenceis both part of a larger system and a combination of smaller systems?
At every level we are a part of an larger system, which is in turn part of an even larger system. No matter where you live, you are part of a community or town or city. This is in turn part of a county, which is part of a state, then a country, then a continent, then the world, solar system, galaxy, universe, etc. Or with a different approach you are part of a personality, which can connect to other personalities, which connect to even more personalities, forming a human network.
At the same time you are a combination of smaller systems. Biologically you are part of a family, in your community. You are then made up of internal systems, muscles, respiratory etc, these are then made up of cells, which are made up of organelles, which are made up of molecules, which are made up of atoms, which are made up of electrons, protons and neutrons. It gets smaller and smaller. With a different approach, your personality is connected to others, but at the same time you are a combination of your feelings, your memories, your looks and character. Each are composed of smaller parts, your memories have distinct characteristics etc.
Discuss the significance of endorphins, and explain how drugs influence transmitters.
Don't know too much about endorphins other than they make you happy and stop you from feeling pain. I am sure wikipedia can help you. Essentially though they bind to transmitters, intercepting one signal from happening. Drugs do the same thing, they stop one signal and start other pathways that aren't usually run or not run in that manner/environment.
Describe how nerve cells communicate,and discuss the importance of neurotransmitters for human behavior.
Neurotransmitters are everything of human behavior. Nerve cells communicate by sending electrical impulses to other nerve cells, which trigger pathways and chemical reactions. One nerve signal can cascade down and cause a pathway to move leading towards widespread cellular contraction meaning muscle movement. This movement can depict your personality, either a friendly wave or flipping someone the bird. That is how the neurotransmitter can effect human behavior.
I think most of that makes sense, hope it helps!
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