Chapter 1 – The Human Body: An Orientation
Unit 1 Overview Lab Terms, Topics, and Definitions
 An Overview of Anatomy and Physiology
o Anatomy studies the structure of body parts and their relationship to one another.
o Physiology concerns the function of the body, in other words, how the body parts work
and carry out their life sustaining activities.
 The Language of Anatomy
o Anatomical Position and Directional Terms
 In anatomical position…
 the body is erect with feet slightly apart
 palms face forward
 The thumbs point away from the body
 Directional terms allow us to explain where one body structure is in relation to
another
o Regional terms
 Axial – main axis of our body; head, neck and trunk
 Appendicular – consists of appendages or limbs
o Body Planes and Sections
 Sagittal Plane – a vertical plane that divides the body into right and left parts
 A sagittal plane that lies directly in the midline is the median plane, or
midsagittal plane; all other sagittal planes, offset from the midline, are
parasagittal planes
 Frontal Plane – a vertical plane that divides the body into anterior and posterior
parts; also called a coronal plane
 Transverse plane – a horizontal plane that runs right to left, dividing the body
into superior and inferior parts
o A transverse section is also called a cross section
 Oblique sections are cuts made diagonally between the horizontal and vertical
planes
o Body Cavities and Membranes
 Dorsal Body Cavity – closed body cavity that protects the fragile
nervous system organs and has two subdivisions
o Cranial cavity, in the skull, encase the brain
o Vertebral or spinal cavity, runs within the bony vertebral
column, encloses the spinal cord
 Ventral Body Cavity – more anterior and larger of the closed body
cavities and has two major subdivisions; houses the internal organs
collectively called the viscera, or visceral organs
o Thoracic Cavity – surrounded by the ribs and muscles of the
chest
 Two lateral pleural cavities, which each envelop a lung


Medial mediastinum, which contains the pericardial
cavity, enclosing the heart, and it also surrounds the
remaining thoracic organs (esophagus, trachea, and
large blood vessels)
 Abdominopelvic Cavity – two subdivisions
 Abdominal cavity – contains the stomach, intestines,
spleen, liver, and other organs
 Pelvic cavity – contains the urinary bladder, some
reproductive organs, and the rectum
 Membranes in the ventral body cavity
o Serosa or serous membrane
 Thin, continuous, and double layered
 Parietal membrane – lines cavity walls
 Visceral membrane – lines organs in the cavity
 Layers separated by a thin layer of lubricating fluid,
called serous fluid which is secreted by both
membranes
Other Cavities
 Oral and digestive cavities
 Nasal cavity
 Orbital cavities
 Middle ear cavities
 Synovial cavities