Explanation and Typical Q&As

Nervous System
is the range of stable condition of your internal environment such as temperature and salt levels to support your life (Nowicki 858) [Sammy].
Nervous system helps the body maintain homeostasis
The nervous system is formed by many connected “cells, tissues, and other organs" together control the body’s activities such as thinking and moving (Nowicki 874). When the nervous system receives the information about the inner and outer conditions of the body from the sensor, it will compare that information to a standard point (or the point at which the body works best). If the conditions are lower or higher than the standard point, then the nervous system will send a message to maintain homeostasis (Nowicki 859) [Sammy].

Differences between two parts of the nervous system
Central nervous system (CNS) consists of the brain and the spinal code. It reads the messages from the peripheral nervous system (PNS) and “stores some of these messages for later use”. The peripheral nervous system (PNS) is a complex connected system of nerves that sends the message to the CNS and from the CNS to the body’s organs for functioning. It connects the CNS to many other organs of the body, and it’s long (Nowicki 875) [Sammy].
The nervous system links to many organs of the body
(The Autonomic Nervous System) [Sammy].

Major Nervous System
Nervous system
Nervous system
(Nervous System)(Jun)
-Somatic nervous system(In the Glossary)(J)
-Central nervous system(In the Glossary)(J)
-Peripheral nervous system(In the Glossary)(J)

Stimulus is Something that triggers a change(J)

THE NEURONS - Nervous System Special Cell

It is a type of specialized cell of the nervous system to helps transmit signals throughout the body (Nowicki 876) [Kelly].

external image brain-neuron-types.gif

In order for your nervous system to communicate with each other, these types of neurons interact with each other other.
For example: Sensory Neuron transmit signals to interneuron with will transmit that signal to the CNS, and the CNS will transmit that signal to the motoneuron which will cause your body to response (Nowicki 877) [Kelly].

external image 1_5-braincell.gif

Dendrites - receive signals
Axon - transmit signals
Neurotransmitter - Chemical signal of the nervous system; (electrical impulse turns into neurotransmitter in order to move to other cells)
Synapse - the space where the two neurons meet to transmit signals
external image neuron.jpg

Chemical signals that allow one neuron to stimulate another(Jun)
They are NA+ and K+
When and where is an impulse an electrical signal?(Jun)
Dendrites recieve impulse while Axon carry impulse

From sensing a stimulus to producing a response, how do your CNS and PNS work together?
They pass signal between one another.
PNS passes impulse to CNS.
CNS interprets impulse.
CNS passes impulse to PNS
PNS stimulates a response.

How is a reflex arc different from other responses?
A reflex arc is a neural pathway that controls an action reflex.
external image reflexarc.jpg

What is the difference between the two parts of the PNS?
sympathetic nervous system: “fight vs. flight” or control body action.
parasympathetic nervous system: calms the body, conserves energy
external image si2012.jpg

Endocrine System
How does the endocrine system help the body maintain homeostasis?
They produce hormones that help control body activities, for example, they might slightly increase body temperature so that our body can increase in production of white blood cell.

What are the major organs of the endocrine system?
They are Hypothalamus, Pineal, and glands including Pituitary, Parathyroid, Thyroid, Thymus, Adrenal and Pancreas, Ovary or Testis depending on the gender.

external image endocrine_system.jpg

What are hormones?(Jun)external image hormones.jpg(Sheta)(Jun)
Hormones are chemical signal that influence cell activities. They are produce in glands that is in the endocrine system.

How do hormones get transported through the body?(Jun)
They are transported by the circulatory system and they travel with matching receptors.

Conditions that are necessary for a hormone to interact with a cell
Hormones are “the chemical signals made by the endocrine system”. A hormone will interact with a cell that has a specific receptor. The cell will then receive the message. If it interacts with the wrong receptor, then that cell won’t receive any message (Nowicki 896) [Sammy]. Steroid hormones must be non-polar and small to get through the cell membrane.
Hormones interact with the target cells
(Endocrine Primer) [Sammy].

Nervous and Endocrine?
As part of the nervous system, the hypothalamus receives signals, and information such as hunger, thirst and temperature. While inside the brain, the hypothalamus will analyze the info and if something went wrong like the body’s feeling cold, it will sent out chemical signals called hormones to maintain homeostasis and that’s where the endocrine system comes in to play (Nowicki 888, 900) [Kelly].

Nothing's perfect though...
If a releasing hormone continues to be produced after the body reaches its ideal condition for homeostasis then the glands being stimulated won’t stop producing hormones. Hormonal imbalances can occur and the body will be sick instead of fixed (Nowicki 900) [Kelly].

Feedback loops regulate homeostasis
Negative feedback loop is a control system which neutralizes the changes in your body. It tries to make the body conditions come to close to the standard points. It can move the conditions above or below the standard points. So the sensor will detect any changes in the inner and outer of human body. They it will send the message to the control system for it to compare the conditions to a standard point. If the conditions go above or below the standard point, the control system will try to do something (depends on which condition) to make the conditions turn back to the standard point (Nowicki 860) [Sammy].

Works Cited
Nowicki, Stephen. McDougal Littell. Evanston, IL: McDougal Littell, 2008. Print. [Kelly & Sammy]
The Autonomic Nervous System. Digital image. BecomeHealthyNow.com. BecomeHealthyNow.com, Inc. Web. 14 May 2011. <http://www.becomehealthynow.com/popups/autonomic.htm>. [Sammy]
Endocrine Primer. Digital image. EM. McLaughlin Centre, Institute of Population Health, University of Ottawa. Web. 14 May 2011. <http://www.emcom.ca/primer/hormones.shtml>. [ Sammy]
Pearson Prentice Hall. Information Flows through Neurons. Digital image. Web. 15 May 2011. [Kelly]
How Stuff Works. Basic Neuron Types. Digital image. Discovery Fit&Health. Discovery Communications, LLC. Web. 15 May 2011. [Kelly]
Mendoza, Noriecel. The Endocrine System. Digital image. SOIM. Southern Oregon Internal Medicine. Web. 15 May 2011. [Kelly]

"Phantom Limb Syndrome." Http:www.womenandinfants.org/body.cfm?id=388&chunkiid=96857
. Women and Infants. Web. 16 May 2011 <http://www.womenandinfants.org/body.cfm?id=388&chunkiid=96857>.
"Neuron | Brainy Info." Brainy Info | Learning the Secrets of the Mind Together. Brainyinfo. Web. 16 May 2011. <http://brainyinfo.com/neuron/>.
PATTS. Neuron structurw. Digital image. Nervous System: CNS and PNS. PATTS. Web. 16 May 2011. [Kelly].
"Nervous System." Visual Dictionary. Web. 16 May 2011. [Jun]
Sheta, Mostafa. "Hormone Replacement Therapies." Mostafa Sheta, M.D. Web. 16 May 2011.[Jun]