Every move that our bodies make, thinking about a film you saw last night or an essay you need to write for school, shaking off a little bug from the leg, deciding between two things or drinking tea after it cools a bit, every action, reaction is driven by our nervous system. All the information taken in is processed and executed by electrical and chemical signals to and from nervous cells. The nervous system controls all our physiological and psychological reactions. All animals have nervous system, except for very simple ones like sponges (The Nervous System, 2015). Human’s nervous system is probably the most complex one, all of our thoughts, emotions and actions are based on the three principle functions: sensory input, integration,…show more content… Efferent divisions includes also the somatic nervous system that controls skeletal muscle movements. And the autonomic nervous system that controls inner organs such as heart, lungs etc. In the autonomic nervous system there are two divisions: sympathetic, that triggers an action and parasympathetic that relaxes the body. The whole nervous system is made up by nervous cells- neurons, which respond to stimuli and transmit signals along. There are many different types of neurons and different sizes of neurons.
Human’s moods, impulses that flash through the mind or ideas are spurred by the biological condition. Which means that how you think, sense, feel and see the world around you is influenced by chemicals in the brain (The chemical mind, 2014). Every neuron is made up of the cell body, where the DNA information and the mitochondria are stored. Dendrites receive messages, they pick up the electric impulses and activate the action potential that passes the impulses along to the cell body and the axon, which transmits the electrical impulses from the cell body out to other neurons or muscles and so on. The axon is sometimes protected by myelin sheath, which helps speed up the transmission of messages. It shoots the electrical charge to its terminals and toward the neighbouring neuron. The place where one neuron almost touches the other is called synapse, the little gap between two neurons is called the synaptic gap. When the actual potential runs