Body Cavities
• 2 major cavities
–Ventral cavities
–Dorsal cavities
• Other cavities: oral, nasal,
orbital, middle ear, & synovial
Dorsal Cavity
• Posterior region of body
• 2 regions
–Cranial cavity (skull): supports
and protects brain
–Vertebral (spinal) Cavity:
supports and protects spinal
cord
Ventral Cavities
• Anterior region of trunk
• Serosa: thin membrane that
covers the wall of cavity and
outer surface of its organs
–Parietal serosa: lines cavity wall
–Visceral serosa: covers organ
Ventral Cavities cont.
• 2 regions
– 1)Thoracic cavity: subdivided
• contains lungs, heart, trachea,
esophagus, thymus, lymph nodes
• Region between lungs = mediastinum
Ventral Cavities cont.
• 2 regions
– 2)Abdominopelvic cavity: subdivided
• A) Abdominal cavity: superior portion
of abdominopelvic cavity
• Stomach, intestine, spleen, liver
• B) Pelvic cavity:inferior to abdominal
cavity; bladder, reproductive organs, &
rectum
– Serosa is called peritoneum
Other Cavities (Smaller Cavities)
• Oral= teeth & tongue
• Nasal = within nose; left and right
side divided by nasal septum
• Orbital = contains eyes &
associated muscles and nerves
• Middle ear = contains ossicles (ear
bones)
Planes of Section
Transverse Section
Coronal Section
Sagittal Section
Transverse Section (Plane)
(Cross-Section)
• Runs horizontally at right angle
to the vertical axis
• It divides the structure into
superior and inferior regions
Sagittal Section (Plane)
• Runs longitudinally (lengthwise)
and divides the body into left and
right regions
• Midsagittal (median section) =
cut is made down the median
plane of body and left and right
parts are equal in size
Coronal (Frontal) Section
(Plane)
• Runs longitudinally but at a
right angle to sagittal plane
• It divides the body into anterior
and posterior regions
Directional Terms
Term
Definition
Example
Superior
Toward the head
end or upper part
of a structure or
the body; above
Forehead is
superior to the
nose
Inferior (Caudal)
Away from the
Stomach is
head or toward the inferior to the
lower part of a
heart
structure or the
body; below
Directional Terms
Term
Definition
Example
Anterior (Ventral) Toward or at the
front of the body;
in front of
Sternum is
anterior to spine
Posterior (dorsal)
Heart is posterior
to the sternum
Toward or at the
backside of the
body; behind
Directional Terms
Term
Definition
Example
Medial
Toward or at the
Heart is medial to
midline of the
the arm
body; on the inner
side
Lateral
Away from the
Arms are lateral to
midline of the
the chest
body; on the outer
side
Directional Terms
Term
Intermediate
Proximal
Definition
Between a more
medial and more
lateral structure
Example
The armpit is
intermediate
between the
sternum &
shoulder
Close to the origin Elbow is proximal
of the body part or to the wrist
the point of
attachment of a
limb to the body
trunk
Directional Terms
Term
Distal
Definition
Farther from the origin of
a body part or the point of
attachment of a limb to the
body trunk
Superficial Toward or at the body
surface
Example
knee is distal to
the thigh
Deep
Lungs are deep to
the rib cage
Away from the body
surface, more internal
Skin is superficial
to the skeleton
Anatomy
• Study of structure of the body & relationship
of its parts
– Subdivisions
• Gross Anatomy: study of anatomic
structures visible to unaided eye
• Descriptive Anatomy: study of individual
body parts in an ordered fashion. i.e.
nervous system
• Regional Anatomy: study of limited
portions or region of the body. i.e. head &
neck region
Anatomy Subdivisions cont.
• Applied Anatomy: application of
anatomic findings to diagnosis &
treatment of medical disorders
• Comparative Anatomy: comparison
of the structure of different animals
and plants
• Pathologic Anatomy: study of
abnormal, diseased or injured tissue
Anatomy Subdivisions cont.
• Microanatomy: study of anatomic
structures using a microscope
– Cytology: study of cellular structure
• Molecular biology: study of structures at
subcellular level
– Histology: microscopic study of tissues
Anatomy subdivisions cont.
• Developmental Anatomy: Study of
structural changes from conception
– 2 subdivisions:
• Embryology: study of developmental
changes before birth
• Gerontology: study of structural
changes that accompany aging
Cell Diversity