The Human Body: An Orientation
is the centermost region deep to and
surrounding the umbilicus (navel).
is located superior to the umbilical
hypogastric (pubic) region
is located inferior to the
umbilical region (
are located lateral to the hypogastric region (
part of the hip bone).
lie lateral to the umbilical
lef hypochondriac regions
lie lateral to the
epigastric region and deep to the ribs (
Other Body Cavities
In addition to the large closed body cavities, there are several
smaller body cavities. Most of these are in the head and most
open to the body exterior. Figure 1.7 provides the terms that
will help you locate all but the last two cavities mentioned here.
Oral and digestive cavities.
Te oral cavity, commonly called
the mouth, contains the teeth and tongue. Tis cavity is part
of and continuous with the cavity of the digestive organs,
which opens to the body exterior at the anus.
Located within and posterior to the nose, the
nasal cavity is part of the respiratory system passageways.
Te orbital cavities (orbits) in the skull house
the eyes and present them in an anterior position.
When serous membranes are inﬂamed, their normally smooth
surfaces become roughened. Tis roughness causes the organs
to stick together and drag across one another, leading to ex-
cruciating pain, as anyone who has experienced
ﬂammation of the pleurae) or
(inﬂammation of the
Abdominopelvic Regions and Quadrants
Because the ab-
dominopelvic cavity is large and contains several organs, it helps
to divide it into smaller areas for study. Medical personnel usu-
ally use a simple scheme to locate the abdominopelvic cavity or-
. In this scheme, a transverse and a median
plane pass through the umbilicus at right angles. Te four re-
sulting quadrants are named according to their positions from
the subject’s point of view: the
right upper quadrant (RUQ)
lef upper quadrant (LUQ)
right lower quadrant (RLQ)
lef lower quadrant (LLQ)
Another division method, used primarily by anatomists, uses
two transverse and two parasagittal planes. Tese planes, posi-
tioned like a tic-tac-toe grid on the abdomen, divide the cavity
into nine regions
Outer balloon wall
(comparable to parietal serosa)
Air (comparable to serous cavity)
Inner balloon wall
(comparable to visceral serosa)
(a) A fist thrust into a flaccid balloon demonstrates
the relationship between the parietal and visceral
serous membrane layers.
(b) The serosae associated with the heart.
Serous membrane relationships.
The four abdominopelvic quadrants.
scheme, the abdominopelvic cavity is divided into four quadrants by