Nervous+and+Endocrine+System

Example of Homeostasis: Whenever the temperature is too hot, you sweat. The amount of water inside your body decrease, so by drinking water you will help your body maintain homeostasis
 * Nervous System** (Rainy)   ﻿ Your body has many control systems that keep its internal environment stable. Together, these control systems are responsible for maintaining homeostasis. Homeostasis is the regulation and maintenance of the internal environment-temperature, fluids, salts, pH, nutrients, and gases-within the narrow ranges that support human life. For more information about homeostasis, click [|here] (Nowicki 858)

**[|Nervous System]:** Different systems communicate through Stimulus -Stimulus is the defined most broadly as something that causes a response (Nowicki 874) The nervous system responds quickly to change, whether from outside conditions or internal ones There are 2 parts of the Nervous System: The CNS interprets messages from the other nerves in the body and stores some of these messages for later use. The PNS transmit messages to the CNS and from there, it transmit to other organs in the body (Nowicki.875) Central neruvous system (CNS) includes brain and spinal cord (Nowicki 875)



There are two part of PNS: -Autonomic nervous system controls involuntary muscles, such as smooth and cardiac organs. Somatic nervous system controls skeletal system as well as external sensory organs such as the skin (Bailey)

CNS and PNS works together: CNS read messages from other nerves in the body and stores some of these messages for later use. PNS is the network that transmits message to CNS and from CNS to other organs in the body (Nowicki 875) More information about 2 part of Nervous System: [|CNS and PNS]



** Neurons: ** Neurons are the specialized cell that stores information and carries messages within the nervous system and between other body systems. Most neurons have three main parts such as 1. Cell Body 2. Dendrites and 3. Axon (Nowicki 876) Dendrites are branchlike extension of the cytoplasm and the cell membrane that receive messages from neighboring cells. A neuron can has more than one dendrite, and each can have many branches (Nowicki 876) Axon is a long extension that carries electrical messages away from cell body and passes them to other cells. A neuron has one axon (Pg.876) Motor neurons and sensory neurons are located in Interneuron part of the nervous system (Nowicki 877) Neurons stimulate another through chemical signals called Interneuron (Nowicki 877) Dendrites are parts in neuron that receives signals (Nowicki 876) For more information about [|Neuron, its structures and its functions.] Neurons transmit information in the form of electrical and chemical impulses. Neurons is stimulated, it produces an electrical impulse that travels only within that neuron. Before the signal can move to the next cell, it changes into a chemical signal (“Nervous System”)

====When the neuron is in resting potential, there wouldn’t be any signal transferring. So “the inside of its cell membrane is more negatively charged than the outside” (Nowicki 877). To be more specific, there are more of K+ inside the cell as more of NA+ outside the cell (Nowicki 877). When electrical impulse moving down the axon that started by something that caused respond, or stimulus, then the neuron is in __[|action potential] __. Therefore, Na+ comes inside to make it become positive while the K+ leaves. Sodium-potassium pump is involved when the area of positive charge moves. Before going to the next neuron for action potential, there is a little space between the neurons needed to be close called a synapse. Then the terminal, one part of an axon would wait to receive the chemical vesicles from the impulse of the neuron. The chemical signals that received is also known as__[|neurotransmitters] __. It got released to continue the action potential at another neuron when the vesicles touch the terminal’s membrane that caused Na+ to opens. ====



There are three types of neurons: (1) sensory neurons (2) interneurons and (3) motor neurons (Pg.877) Sensory neurons detect stimuli and transmit signals to the brain and the spinal cord, which are both made up of interneurons. Interneurons receive signals from sensory neurons and relay them within the neurons. Motor neurons pass messages from the nervous system to other tissues in the body (Nowicki 877)

Nowicki, Stephen. "Nervous System." McDougal Littell Sinh học.Evanston,  IL: McDougal Littell, 2008. 938-69. Print. ** Pictures: ** [] [] [] [] [] []
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** WORK CITED   ** Nowicki, Stephen. "Nervous System." McDougal Littell Sinh học.Evanston, IL: McDougal Littell, 2008. 938-69. Print. Bailey, Regina. "Peripheral Nervous System." // Biology //. About.com Guide, 2011. Web. 16 May 2011.  "Nervous System Information." University of Pennsylvania Health System | Penn Medicine. Web. 15 May 2011. [].

Questions: What is a stimulus? What are neurons? What part of the neuron receives signals? To what part of the nervous system do motor neurons and sensory neurons belong? What is the electrical impulse that moves down an axon called? What are the chemical signals that allow one neuron to stimulate another? From sensing a stimulus to producing a response, how do your CNS and PNS work together? How is a reflex arc different from other responses? What are the difference between the two parts of the PNS?

When and where is an impulse an electrical signal?