Zoo. 121 lab
Activity #2
Anatomical position, regions and cavities of the human body
Anatomical Position
The anatomical position is a standardized method of observing or imaging the body that
allows precise and consistent anatomical references.
When in the anatomical position, the subject stands erect facing the observer, the feet
are flat on the floor, toes pointing forward, upper appendages are laterally positioned with the
palms facing frontally.
Reclining Position
If the body is lying face down, it is in the prone position. If the body is lying face up, it is
in the supine position.
Regional Terms
Regional terms are used to designate specific body areas:
1. AXIAL DIVISION (Torso)
2. APPENDICULAR DIVISION (Limbs)
Regional Names
Regional names are names given to specific regions of the body for reference:
1. cranial - skull
2. thoracic - chest
3. brachial – arm
4. patellar – knee
5. cephalic – head
6. gluteal – buttock
Planes
Planes are imaginary flat surfaces that are used to divide the body or organs into definite
areas:
1. Midsagittal (medial)
2. parasagittal
3. frontal (coronal)
4. transverse (cross-sectional or horizontal)
5. oblique.
Sections
Sections are flat surfaces resulting from cuts through body structures. They are named
according to the plane on which the cut is made.
1. transverse
2. frontal
3. midsagittal
Directional Terms
Directional terms are used to precisely locate one part of the body relative to another and
to reduce length of explanations.
1. Cephalic
2. Cranial
3. Rostral
4. Caudal
5. Superior
6. Inferior
7. Anterior
8. Posterior
9. Dorsal
10. Ventral
11. Superficial: toward surface
12. Deep: away from surface
13. Medial: toward midline
14. Lateral: away from midline
15. Intermediate: between 2 points
16. Ipsilateral: same side
17. Contralateral: opposite side
18. Proximal: near origin
19. Distal: away from origin
20. External (Outer)
21. Internal (Inner)
22. Central
23. Peripheral
24. Parietal
25. Visceral
Areas
1.Head & Neck
2. Trunk
3. Thorax
4. Abdomen
5. Pelvis & Perineum
6. Extremities (or limbs)
a. Upper
b. Lower
Body Cavities
Body cavities are spaces within the body that help protect, separate, and support internal
organs.
1. Dorsal Body Cavity
 The dorsal body cavity is located near the dorsal (back) surface of the body and
has two subdivisions, the cranial cavity and the vertebral canal.
a. Cranial cavity is formed by the cranial bones and contains the brain.
b. Vertebral (spinal) canal is formed by the bones of the vertebral column and
contains the spinal cord.
 Three layers of protective tissue, called meninges, line the dorsal body cavity.
2. Ventral Body Cavity
 Ventral Body Cavity is subdivided by the diaphragm into an upper thoracic cavity and
a lower abdominopelvic cavity.
a. Thoracic cavity contains two pleural cavities, and the mediastinum, which
includes the pericardial cavity. Upper thoracic cavity includes the pleural cavities
enclose the lungs, while the pericardial cavity surrounds the heart.
The mediastinum is a broad, median partition between the lungs that extends
from the sternum to the vertebral column, it contains all contents of the thoracic
cavity except the lungs.
The pericardial cavity encloses the heart and great vessels.
b. Abdominopelvic cavity is divided into a superior abdominal and an inferior
pelvic cavity.
 Viscera of the abdominal cavity include the stomach, spleen, pancreas, liver,
gallbladder, small intestine, and most of the large intestine
 Thoracic and Abdominal Cavity Membranes: A thin, slippery serous
membrane covers the viscera within the thoracic and abdominal cavities and
also lines the walls of the thorax and abdomen.
Parts of the serous membrane are the parietal layer which lines the walls of
the cavities and the visceral layer which covers and adheres to the viscera
within the cavities.
 Serous fluid between the two layers reduces friction and allows the viscera
to slide somewhat during movements. The serous membranes include the
pleura, pericardium and peritoneum.
Other Body Cavities
1. Oral and digestive – mouth and cavities of the digestive organs
2. Nasal –located within and posterior to the nose
3. Orbital – house the eyes
4. Middle ear – contain bones (ossicles) that transmit sound vibrations
5. Synovial – joint cavities
Procedure:
1. Illustrate the following:
a. human anatomical position
b. reclining position
c. Regional Terms
d. Regional Names
e. Planes
f. Sections
g. Directions
h. Areas
i. Body cavities
k. Other body cavities
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.