Directional Terms, Planes, Sections, Cavities and Quadrants Flashcards
(24 cards)
Superior (cephalic or cranial)
Towards the head, or the upper part of a structure The heart is superior to the liver
Inferior (caudal)
Away from the head, or the lower part of a structure The stomach is inferior to the lungs
Anterior (ventral)
Nearer to or at the front of the body The sternum (breastbone) is anterior to the heart
Posterior (dorsal)
Nearer to or at the back of the body The oesophagus (food tube) is posterior to the trachea (windpipe)
Medial
Nearer to the midline (an imaginary vertical line that divides the body into equal right and left sides) The ulna is medial to the radius
Lateral
Farther from the midline The lungs are lateral to the heart
Intermediate
Between two structures The transverse colon is intermediate to the ascending and descending colons.
Ipsilateral
On the same side of the body as another structure The gall bladder and ascending colon are ipsilateral
Contralateral
On the opposite side of the body from another structure The ascending and descending colons are contralateral
Proximal
Nearer to the attachment of a limb to the trunk; nearer to the origination of a structure. The humerus (arm bone) is proximal to the radius
Distal
Farther from the attachment of a limb to the trunk; farther from the origination of a structure The phalanges (finger bones) are distal to the carpals (wrist bones)
Superficial (External)
Towards or on the surface of the body The ribs are superficial to the lungs
Deep (Internal)
Away from the surface of the body The ribs are deep to the skin of the chest and back
Sagittal Plane
This plane divides the body into left and right parts. The midsagittal, or median, plane specifically refers to a sagittal plane that runs down the center of the body, dividing it into equal left and right halves. Planes parallel to the midsagittal plane are known as parasagittal planes.
Coronal plane (Frontal plane)
This plane divides the body into anterior (front) and posterior (back) portions. It runs vertically from one side of the body to the other and is perpendicular to the sagittal plane.
Transverse Plane (Horizontal Plane)
This plane divides the body into superior (upper) and inferior (lower) parts. It runs horizontally from one side of the body to the other, perpendicular to both the sagittal and coronal planes.
Sagittal Section
Sagittal Section: A cut made along a sagittal plane. A midsagittal section would split the body into equal left and right halves, commonly seen in diagrams showing the brain or spinal column.
Coronal Section
A cut made along a coronal plane. This is often used to view the front or back halves of structures such as the brain or the thoracic cavity, providing a good view of the front or back organs and structures.
Transverse Section (Cross Section)
A cut made along a transverse plane, producing images that are viewed as if from the top down. This is common in CT scans of the torso, where cross-sectional images can show layers of the abdominal or chest organs.
Dorsal Body Cavity
The dorsal body cavity is located along the posterior (back) side of the body and is divided into two main sub-cavities:
Cranial Cavity: This cavity is within the skull and encases the brain. It provides rigid support and protection due to the surrounding bone structure.
Vertebral (Spinal) Cavity: Running through the vertebral column, this cavity encloses the spinal cord and the beginnings of the spinal nerves. It is also heavily protected by the vertebrae.
Ventral Body Cavity
The ventral body cavity is larger and is located along the anterior (front) aspect of the torso. It is divided into the thoracic cavity and the abdominopelvic cavity.
Thoracic Cavity
Thoracic Cavity: This cavity is above the diaphragm, enclosing the lungs and heart, among other structures. It is further divided into:
Pleural Cavities: Each houses a lung and is lined by a two-layered membrane called the pleura.
Mediastinum: This central compartment contains the heart (within the pericardial cavity), trachea, esophagus, and other structures.
Pericardial Cavity: Located within the mediastinum, this cavity encloses the heart and is lined by the pericardium, a two-layered sac.
Abdominopelvic Cavity
Abdominopelvic Cavity: Below the diaphragm, this cavity is separated from the thoracic cavity by the diaphragm and is subdivided into:
Abdominal Cavity: Contains many digestive organs, such as the stomach, intestines, liver, and pancreas, as well as other organs like the kidneys and spleen.
Pelvic Cavity: Contains the urinary bladder, some reproductive organs, and the rectum. The pelvic bones surround and protect this cavity.
Abdominopelvic Quadrants
