Body Planes, Directions, & Cavities

Principles of Health Science

Body Cavities

Why do we have body cavities?

Body Cavities are openings within the torso which contain organs.

They protect delicate organs from accidental shocks and bumps, and permit the expansion and contraction of organs without disrupting the activities of other organs.

Body Planes

Imaginary lines drawn through the body to separate the body into sections Transverse Sagittal Frontal or coronal

Transverse plane

Horizontal plane that divides the body into a top & bottom half

Sagittal plane

Divides the body into left and right sides

Midsagittal divides the body into equal left and right sides

Frontal (or coronal) plane

Divides the body into a front and back section

Directions

Superior vs inferior Cranial vs caudal Medial vs lateral Anterior vs posterior Dorsal vs ventral Proximal vs distal

Superior vs inferior

Superior: towards the top

Inferior: towards the bottom

Cranial vs caudal

Cranial: towards the head

Caudal: towards the tail

More commonly used in animals

People: same as superior/inferior

Medial vs lateral

Medial: close or towards the midline

Lateral: away from the midline

Anterior vs posterior

Anterior: towards the front of the body

Posterior: towards the back of the body

Dorsal vs ventral

Dorsal: towards the back

Ventral: towards the abdomen

Use more commonly in animals

People: same as anterior/posterior

Proximal vs distal

Proximal: towards the trunk

Distal: away from the trunk

Body Cavities

Dorsal cavity Cranial cavity Spinal cavity

Ventral cavity Thoracic cavity Abdominopelvic

cavity Abdominal cavity Pelvic cavity

Orbital cavity (eyes) Nasal cavity (nose) Buccal cavity

(mouth)

Dorsal cavity

Cranial cavity: contains the brain

Spinal cavity: contains the spinal cord

Ventral cavity

Thoracic cavity: contains esophagus, heart, lungs, trachea

Abdominopelvic cavity Abdominal cavity: stomach, small intestine,

liver, gallbladder, pancreas, spleen Pelvic cavity: urinary bladder, reproductive

organ Diaphragm: muscle that separates the

thoracic cavity from the abdominopelvic

The portion of ventral cavity superior to the diaphragm.

a. Pleural Cavities - the spaces surrounding each lung.

b. Mediastinum - a broad middle tissue mass of the thoracic cavity dividing the lungs into two cavities.

Thoracic Cavity

It includes the aorta, other great blood vessels, esophagus, trachea, thymus, pericardial cavity, and heart.

c. Pericardial Cavity - space in which the heart is located

Abdominal Cavity

Abdominal Cavity - The superior portion of the abdominopelvic cavity. It extends from the diaphragm to the superior margin of the pelvic girdle.

Contains the organs known as the viscera which include the stomach, spleen, liver, gallbladder, pancreas, small intestine, and most of the large intestine.

Pelvic Cavity

Surrounded by the pelvic bones. The pelvic cavity contains the urinary

bladder, cecum, appendix, sigmoid colon, rectum, and the male or female internal reproductive organs

Abdominal quadrants

Four quadrants with the umbilicus at the center RUQ

LUQRLQLLQ

Abdominal regions

Image Citations Slide 3: 8/27/06,

http://academic.kellogg.cc.mi.us/herbrandsonc/bio201_McKinley/chapter1.htm

Slide 4: Sagittal plane, 8/27/06, http://www.tech.nite.go.jp/human/eng/contents/cindex/referencedevelop.html

Slide 5: Frontal plane, 8/27/06, http://www.tech.nite.go.jp/human/eng/contents/cindex/referencedevelop.html

Slide 7 & 9 &12: Directional terms, 8/27/06, http://www.lrn.org/Graphics/figure1.7.gif

Slide 8: Anatomical terms, planes, 8/27/06, http://trc.ucdavis.edu/mjguinan/apc100/modules/termscells&tissues/introduction/planes/planes.html

Image Citations

Slide 11: photo of a dog illustrating dorsal, ventral, anterior and posterior, 8/27/06, http://anthro.palomar.edu/animal/glossary.htm#bilateral_symmetry

Slide 14: Body cavities, 8/31/06, http://www.templejc.edu/dept/biology/RHicks/biol2404Int/biol2404onl_LAB.htm

Slide 16, 17: Delmar Learning’s Medical Terminology Image Library, Second Edition, Version 1.0, 2003.