To visualize structural arrangements of various organs, the body may be sectioned (cut) according to planes of reference.
The three major planes are the frontal, median, and horizontal planes, as shown in Figure 2–2. In addition, body cavities, as shown in Figure 2–3, contain internal organs and are used as a point of reference to locate structures within body cavities.
Body Planes
2–34 Review Figures 2–2 and 2–3 before proceeding with the next frame. You may refer to the two figures to complete the following frames.
2–35 A body plane is an imaginary flat surface that divides the body into two sec- tions. Different planes divide the body into different sections, such as front and back, left side and right side, and top and bottom. These planes serve as points of reference for describing the direction from which the body is being observed. Planes are partic- ularly useful to describe views in which radiographic images are taken.
An imaginary flat surface that divides the body into two sections is a ____________________ ____________________.
Frame 2–34to Frame 2–35 Body Planes and Cavities • C H A P T E R 2 41
body plane
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2–36 Examine Figure 2–2 and list the three major planes of the body.
____________________ (____________________) ____________________ (____________________) ____________________ (____________________)
When in doubt about the meaning of a word element, refer to Appendix A, page 548.
2–37 The median (midsagittal) plane lies exactly in the middle of the body and divides the body into two equal halves. (See Fig. 2–2.)
When the chest is divided into equal right and left sides, it is divided by the median plane, also known as the ____________________ __________.
Boldfaceindicates a word root or combining form. Blueindicates a suffix. Pinkindicates a prefix.
42 C H A P T E R 2 • Body Structure
(1) Cranial
(2) Spinal Dorsal
(4) Thoracic
(6) Abdominal
(7) Pelvic
Ventral (3) Diaphragm
(5) Abdomino- pelvic
Figure 2-3 Body cavities, with the ventral (anterior) cavities located in the front of the body and the dorsal (posterior) cavities located in the back of the body.
median (midsagittal) mĭd-SĂJ-ĭ-tăl
frontal (coronal) kŏ-rō-năl
horizontal (transverse) trăns-VĔRS
!
midsagittal plane mĭd-SĂJ-ĭ-tăl
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2–38 When the lungs are divided into equal right and left sides, they are divided by the midsagittal plane, also known as the ____________________ __________.
2–39 The horizontal (transverse) plane runs across the body from the right side to the left side and divides the body into upper (superior) and lower (inferior) portions. Figure 2–2 shows the division of this plane.
Recall the term super/ior. It is a point of reference that refers to a structure above or oriented toward a higher place. For example, the head is superior to the heart.
Infer/ior is a point of reference that refers to a structure situated below or oriented toward a lower place. For example, the feet are inferior to the legs.
Because the head is located superior to the heart, the heart is located __________ / __________ to the head. Because the feet are located inferior to the legs, the legs are located __________ / __________ to the feet.
2–40 The plane that divides the body into superior and inferior portions is the horizontal plane. This plane is also called the ____________________
__________.
2–41 Many different trans/verse planes exist at every possible level of the body, from head to foot. A trans/verse section is also called a cross-sectional plane.Some radiographic imaging devices produce cross-sectional images. Cross-sectioning of the body or of an organ along different planes results in different views.
In radiography, the horizontal, or trans/verse, plane is also known as the ____________________ plane.
2–42 A radi/o/graph of the liver along a trans/verse plane results in a different view than a radiograph along the frontal plane. That is why a series of x-rays is com- monly taken using different planes. Views along different planes result in a complete and comprehensive image of a body structure.
Identify the elements in this frame that mean instrument for recording: __________
radiation, x-ray; radius (lower arm bone on thumb side): __________ / _____
through, across: __________
turning: __________
2–43 Locate the frontal plane in Figure 2–2. The frontal plane is also called the ____________________ __________.
Frame 2–36to Frame 2–43 Body Planes and Cavities • C H A P T E R 2 43
median plane
infer/ior, super/ior ĭn-FĒ-rē-or,
soo-PĒ-rē-or
transverse plane trăns-VĔRS
cross-sectional
-graph radi/o trans- -verse
coronal plane CŎR-ŏ-năl
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2–44 The frontal (coronal) plane is commonly used to take an anter/o/poster/ior (AP) chest radiograph, indicating that the x-ray beam enters the body on the anterior side and exits the body on the ____________________ / __________ side. The radi- ograph produced shows a view from the front of the chest toward the back (of the body).
2–45 In the previous frame, you learned that anter/o/poster/ior is used in radi/o/logy to describe the direction or path of an x-ray beam. The CF radi/o means radiation; x-ray; radius (lower arm bone on thumb side).
The suffix -logy means ____________________ __________.
2–46 Use radi/oto form a word that means study of radiation or x-rays:
__________ / _____ / __________.
2-47 Identify the abbreviation in Frame 2–45 that designates the path of an x-ray beam from the anterior to the posterior part of the body: __________.
Body Cavities
2–48 Body cavitiesare hollow spaces within the body that help protect, separate, and support internal organs. There are four body cavities: two dors/al cavities, which are located in the back (posterior) part of the body, and two ventr/al cavities, which are located in the front (anterior) part of the body. The thorac/ic and abdominal cavities are separated by a muscular wall known as the diaphragm.Because the ab- dominal and pelvic cavities are not separated by a wall, they are commonly referred together as the abdominopelvic cavity.Review Figure 2–3 to study the location of the dors/al cavities.
2–49 The dors/al cavity is subdivided into the (1) crani/aland (2) spin/alcavi- ties. The crani/al cavity is encased by the skull and contains the brain; the spin/al cavity contains the spinal cord.
Practice building words that refer to the body cavities by building a term that means pertaining to the cranium (skull): __________ / __________
pertaining to the spine: __________ / __________
2–50 The (3) diaphragm is a dome-shaped muscle that plays an important role in breathing. It separates the thorac/ic cavity from the abdomin/o/pelv/ic cavity. Lo- cate the diaphragm in Figure 2–3.
2–51 Let us review some of the elements in the previous frame. Indicate the root that refers to the
pelvis: ____________________
chest: ____________________
abdomen: ____________________
Boldfaceindicates a word root or combining form. Blueindicates a suffix. Pinkindicates a prefix.
44 C H A P T E R 2 • Body Structure
poster/ior pŏs-TĒ-rē-or
study of
AP
crani/al KRĀ-nē-ăl spin/al SPĪ-năl
pelv thorac abdomin radi/o/logy rā-dē-ŎL-ō-jē
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2–52 The major body cavities of the trunk are the thorac/ic and abdomin/o/
pelv/ic cavities. The (4) thoracic cavitycontains the heart and lungs, and the (5) abdominopelvic cavity contains the digestive and reproductive organs. The abdomin/o/pelv/ic cavity contains by far the greatest number of organs of any of the body cavities and is further subdivided into the (6) abdominal and (7) pelvic cavities. Locate these cavities in Figure 2–3.
2–53 Review Figure 2–3 to identify the largest cavity in the body that incorporates the abdomin/o/pelv/ic and thorac/ic cavities: __________ / __________
_______________
2–54 Medical personnel locate a structure of interest by referring to the body cav- ity in which it can be found.
Use the terms super/ior and infer/ior to describe locations, or positions, of body cavities.
The thoracic cavity is located __________ / __________ to the abdominopelvic cavity.
The spinal cavity is located __________ / __________ to the cranial cavity.