ANATOMY AND PHYSIOLOGY
Knowledge of how the human body is constructed
and how it works is an important part of the training of
everyone concerned with healing the sick or managing
conditions following injury. This chapter will provide
you with a general knowledge of the structures and
functions of the body.
The human body is a combination of organ
systems, with a supporting framework of muscles and
bones and an external covering of skin. The study of
the body is divided into three sciences:
Anatomythe study of body structures and the
relation of one part to another.
Physiologythe study of the processes and
functions of the body tissue and organs. Physiology is
the study of how the body works and how the various
parts function individually and in relation to each other.
Embryologythe study of the development of
the body from a fertilized egg, or ovum.
TERMS OF POSITION AND
anatomical terms of position and direction.
The planes of the body are imaginary lines
dividing it into sections. These planes are used as
reference points in locating anatomical structures. As
shown in figure 1-1, the median, or midsagittal, plane
divides the body into right and left halves on its vertical
axis. This plane passes through the sagittal suture of
the cranium; therefore, any plane parallel to it is called
a sagittal plane . Frontal planes are drawn
perpendicular to the sagittal lines and divide the body
into anterior (front) and posterior (rear) sections. Since
this line passes through the coronal suture of the
cranium, frontal planes are also called coronal planes.
The horizontal, or transverse, plane, which is drawn
at right angles to both sagittal and frontal planes,
divides the body into superior (upper) and inferior
To aid in understanding the location of anatomical
structures, you should use a standard body position
called the anatomical position as a point of reference.
This anatomical position is assumed when the body
Figure 1-1.Planes of the body.