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= = [|**Glossary**] [|**Homeostasis**] = =
 * Key Notes**
 * All physiological functions are performed by anatomical structures. These functions follow the same physical and mechanical principles that can be seen in the world at large.
 * The body can be divided into 11 organ systems, but all work together and the boundaries between them aren’t absolute.
 * Physiological systems work together to maintain a stable internal environment, the foundations of homeostasis. In doing so they monitor and adjust the volume and composition of body fluids, and keep body temperature within normal limits. If they cannot do so, internal conditions become increasingly abnormal and survival becomes uncertain.
 * Anatomical descriptions refer to an individual in the anatomical position: standing, with the hands at the sides, palms facing forward, and feet together.

Anatomical Position
Before studying anatomy, a student should become aware of some of the vocabulary that is used to describe various aspects of the human body. If everyone uses the same terminology, then it is easier to understand what each of us is trying to say. So, before learning the particulars about the anatomy of a region, we will take a look at some of the terminology. For the purpose of description, the body is considered as being in what is called the. "anatomical position". We will use a skeleton to describe this position. In this Anatomical Position, the body is assumed to be standing, the feet together, the arms to the side, and the head and eyes and palms of the hands facing forwards. To ensure consistency of description it is important to keep the anatomical position constantly in mind. This last point is an important one, since in a normal relaxed position of the body, the thumb points anteriorly. In anatomical parlance, the thumb is a lateral structure, not an anterior one. Here's the Anatomical Position as shown by a skeleton:
 * Anatomical Position || [[image:http://mywebpages.comcast.net/wnor/skeletonant.jpg align="center"]] ||

[|Abdominopelvic Quadrants and Regions]

A. Dorsal (Posterior) Body Cavity 1. Cranial Cavity - brain 2. Vertebral Cavity - spinal cord B. Ventral (Anterior) Body Cavity 1. Thoracic Cavity (chest cavity) a. Pleural - 2 cavities around the lungs b. Mediastinum - the cavity between the lungs c. Pericardial - cavity containing the heart 2. Abdominopelvic Cavity a. Abdominal Cavity - digestive system organs b. Pelvic Cavity - reproductive organs and bladder
 * BODY CAVITIES**

=**Directional Terms:**=



Anatomical Planes of the Body
Second, you will consider the planes of the body. Understanding these will facilitate learning terms related to position of structures relative to each other and movement of various parts of the body. =**PLANES AND SECTIONS**= Midsaggital— a plane that divides a bilaterally symmetrical organism into two mirror image halves.
 * FRONTAL (or coronal) separates the body into Anterior and Posterior parts MEDIAN (or midsagittal) separates body into Right and Left parts HORIZONTAL separates the body into Superior and Inferior parts SAGITTAL any plane parallel to the median plane || [[image:http://mywebpages.comcast.net/wnor/Anatplns.jpg align="center"]] ||

Parasaggital—a plane that divides a bilaterally symmetrical organism into two unequal halves.

Frontal or Coronal—a plane dividing a bilaterally symmetrical organism into a front and a back half.

Transverse **(cross-sectional)** —a plane passing through a structure or organism that is at a 900 angle to the long axis of the structure.

Oblique—a plane passing through a structure or organism that is at an angle other than 900.

After taking a look at the Anatomical Planes, you can then view some of the terms related to the planes. These are listed in the following tables. You will notice that most of these are in pairs of opposites.

Terms of relation or position

 * superior //(closer to the head)// || inferior //(closer to the feet)// || reference point -- horizontal plane ||
 * posterior (dorsal) //**closer to the posterior surface of the body**// || anterior (ventral) //**closer to the anterior surface of the body**// || reference point -- frontal or coronal plane ||
 * medial //**(lying closer to the midline)**// || lateral //**(lying further away from the midline)**// || reference point -- sagittal plane ||
 * proximal //**closer to the origin of a structure**// || distal //**further away from the origin of a structure**// || reference point -- the origin of a structure ||
 * superficial || deep || reference point -- surface of body or organ ||
 * median ||  || reference point -- along the midsagittal or median plane ||
 * intermediate ||  || between two other structures ||
 * external || internal || refers to a hollow structure **(external being outside and internal being inside)** ||
 * supine- face up || prone- face down || **face or palm up when lying on back, face or palm down when lying on anterior surface of body** ||
 * cephalad || caudad || toward the head, toward the tail (feet) ||
 * cephalad || caudad || toward the head, toward the tail (feet) ||

Terms of movement

 * flexion || extension || increasing angle with frontal plane //decreasing angle with frontal plane// ||
 * abduction || adduction || moving away from or toward the sagittal plane ||
 * protraction || retraction || moving forward or //backward along a surface// ||
 * elevation || depression || raising or lowering a structure ||
 * medial rotation || lateral rotation || movement around an axis of a bone ||
 * pronation || supination || placing palm backward or forward (in anatomical position) ||
 * circumduction ||  || combined movements of flexion, extension, abduction, adduction medial and lateral rotation circumscribe a cone ||
 * opposition ||  || bringing tips of fingers and thumb together as in picking something up ||
 * opposition ||  || bringing tips of fingers and thumb together as in picking something up ||

=**BODY REGION NAMES**=

Some terms used to describe anterior body regions.
 * [[image:http://www.mhhe.com/biosci/esp/2002_general/Esp/folder_structure/le/m1/s7/assets/images/lem1s7_1.jpg]] || [[image:http://www.mhhe.com/biosci/esp/2002_general/Esp/folder_structure/le/m1/s7/assets/navigation/transparent.gif width="2" height="1"]] ||