Body Regions and Locations

Introduction

There are 10 different systems that reside within the human body. Each system is responsible for performing different tasks. The human body relies on the functions of each body system to maintain good health conditions. As we go along, we'll discuss the different body systems in greater detail. However, before we can through the functions of each system, we'll need to discuss the locations of each system.

 

Planes of the Body

To picture the relative locations of organs in the body, it's helpful to think of them as occupying imaginary planes, or sections of body space. X-ray images are often taken along these planes. There are three major types of planes:

1. The frontal or coronal plane divides the body vertically, into anterior and posterior portions.
2. A sagittal plane also divides the body vertically, but into right and left parts.                                                                                                                        A midsagittal plane goes through the exact median of the body, dividing it into two near-mirror images.
3. A transverse or cross-sectional plane divides the body horizontally, into superior (upper) and inferior (lower) parts.

 

Quadrants and Regions

The body as a whole can be divided into two major cavities. A cavity is a hollow place or space within the body or one of the body's organs.

The axial portion includes the head, neck, and torso or trunk. The appendicular portion includes the appendages of the body, or extremities, better known as limbs. Axial and appendicular portions each contain specific anatomical regions of the body.

The axial portion contains two major cavities, the dorsal and ventral cavities, and these are further subdivided. The dorsal cavity is subdivided into the cranial cavity (houses the brain) and the spinal cavity (vertebral canal).

The spinal cavity is divided into the following sections:

• Cervical (neck)—contains vertebrae C-1 to C-7.
• Thoracic (chest)—contains vertebrae T-1 to T-12.
• Lumbar (loin)—contains vertebrae L-1 to L-5.
• Sacral (lower back)—contains fused vertebrae S-1 to S-5.
• Coccyx (tailbone)

 

The ventral cavity is subdivided into the thoracic and abdominal cavities. The abdominopelvic cavity is the largest ventral cavity and contains the stomach, intestines, kidneys, liver, gallbladder, pancreas, and spleen.

 

Another way of dividing the abdominal cavity is by quadrants. The midline, which divides the right and left quadrants, contains the aorta, pancreas, small intestine, bladder, and spine. 

-The right upper quadrant (RUQ) contains the gallbladder, duodenum, head of pancreas, right kidney and adrenal gland, hepatic flexure of colon, part of the ascending colon, and transverse colon.

-The left upper quadrant (LUQ) contains the stomach, spleen, part of the pancreas, and parts of the large and small intestines.

-The right lower quadrant (RLQ) contains parts of the small and large intestines, the right ovary, the right fallopian tube, the appendix, and the right ureter.

-The left lower quadrant (LLQ) contains the descending colon, sigmoid colon, left ovary and tube, left ureter, and left spermatic cord.

 

Key points

• The supine position, sometimes called the recumbent position, is on the back, face upward. When you lie on your side, either left or right, you're in the lateral recumbent position. Prone is on the belly, face down.
• Superior means "toward the head," and inferior means "toward the feet."
• Sometimes the term cephalic (pertaining to the head) is used to mean "superior," or the term caudal (pertaining to the tail) to mean "inferior."
• The frontal or coronal plane divides the body vertically, into anterior and posterior portions.
• A sagittal plane also divides the body vertically, but into right and left parts. A midsagittal plane goes through the exact median of the body, dividing it into two near-mirror images.
• A transverse or cross-sectional plane divides the body horizontally, into superior (upper) and inferior (lower parts).