Chapter 2: The Language of Anatomy

Anatomy Unit ObjectivesAnatomy Unit Objectives

Verbally describe or demonstrate the anatomical position.

Use proper anatomical terminology to describe body directions, surfaces and body planes

Locate the major body cavities, and list the chief organs in each cavity.

Superficial AnatomySuperficial AnatomyInvolves locating structures on or near

the body surfaceUnderstanding anatomical landmarks,

anatomical regions, and terms for anatomical directions will help you remember both the location of a structure and its name.

For example; the brachium refers to the the arm and the brachialis muscle and the brachial artery are located in the arm.

Why have an anatomical Why have an anatomical position?position?

To prevent misunderstandings, anatomists use universally accepted terms to identify body structures precisely and with a minimum of words

* It is important to remember that the terms “left” and “right” refer to those sides of the person being viewed – not those of the observer.

Anatomical PositionAnatomical Position1. Body erect2. Feet slightly apart3. Palms facing forward 4. Thumbs point away from

body5. Similar to “standing at

attention”

Supine – person laying down in anatomical position face up

Prone – face downFigure 1.7a

Table 1.1

Table 1.1

Check Point

Create 4 examples using the directional terms.

1. Share/Check with a partner. 2. Be prepared to discuss your

examples.

Regional Terms: Anterior Regional Terms: Anterior ViewView

Axial: head, neck, and trunk

Appendicular: arms, legs, and attachments

Figure 1.7a

Regional Terms: Posterior Regional Terms: Posterior ViewView

Figure 1.7b

Body SectionsBody SectionsSagittal – divides the body into right and left parts

Midsagittal or median- sagittal plane that lies on the midline

Body SectionsBody SectionsFrontal/Coronal Section – Lengthwise plane that divides the body (or organ) into anterior and posterior

Body SectionsBody Sections

Transverse/Cross Section – Cut along a horizontal plane dividing the body or organ into superior and inferior parts.

Body PlanesBody Planes

Figure 1.8

Anatomical VariabilityAnatomical Variability

Humans vary slightly in both external & internal anatomy.

Over 90% of all anatomical structures match

textbook descriptions, but: - Nerves or blood vessels may be somewhat

out of place - Small muscles may be missing

Extreme anatomical variations are seldom seen . . .

But it does happen…

Body CavitiesBody Cavities

Dorsal Body Cavity1. Cranial Cavity – Brain 2. Vertebral Cavity – Spinal cord & nerve origins

Ventral Body Cavity1. Thoracic Cavity – Chest cavity

A. Pleural Cavity – LungsB. Pericardial Cavity – HeartC. Mediastinum

2. Abdominopelvic CavityA. Abdominal – stomach, spleen, gallbladder,

liver, pancreas, small & large intestinesB. Pelvic – bladder, portions of large intestines,

sex organs

Body CavitiesBody Cavities

Body CavitiesBody Cavities

◦Cranial cavity is within the skull and encases the brain

◦Vertebral cavity runs within the vertebral column and encases the spinal cord

The Dorsal cavity protects the nervous system, and is divided into two subdivisions:

Body CavitiesBody CavitiesVentral cavity houses the internal organs and is divided into two subdivisions:

1.Thoracic

2.Abdominopelvic

Body CavitiesBody Cavities

The Thoracic cavity is subdivided into :

Mediastinum – contains the pericardial cavity, and surrounds the remaining thoracic organs

Pericardial cavity – encloses the heart

Pleural cavities – each houses a lung

Body CavitiesBody Cavities

Two subdivisions:

◦ Abdominal cavity – contains the stomach, intestines, spleen, liver, and other organs

◦ Pelvic cavity – lies within the pelvis and contains the bladder, reproductive organs, and rectum

The abdominopelvic cavity is separated from the superior thoracic cavity by the dome-shaped diaphragm

Ventral Body Cavity Ventral Body Cavity MembranesMembranes

Parietal serosa lines internal body walls

Visceral serosa covers the internal organs

Serous fluid separates the serosae

Ventral Body Cavity Ventral Body Cavity MembranesMembranes

Figure 1.10a

Other Body CavitiesOther Body Cavities

1. Oral and digestive – mouth and cavities of the digestive organs

2. Nasal - located within and posterior to the nose

3. Orbital – house the eyes

4. Middle ear – contain bones (ossicles) that transmit sound vibrations

5. Synovial – joint cavities

Other Body CavitiesOther Body Cavities

Abdominopelvic RegionsAbdominopelvic Regions

UmbilicalEpigastricHypogastricRight and left

iliac or inguinalRight and left

lumbarRight and left

hypochondriac

Figure 1.11a

Abdominopelvic RegionsAbdominopelvic Regions

Umbilical – Centermost region deep to and surrounding the umbilicus.

Epigastric- located superior to the umbilical region

Hypogastric- located inferior to the umbilical region

Abdominopelvic Abdominopelvic RegionsRegions

Right and left iliac (inguinal)- located lateral to the hypogastric region.

Right and left lumbar-lie lateral to the umbilical region.

Right and left hypochondriac- lie lateral to the epigastric region.

Organs of the Abdominopelvic Organs of the Abdominopelvic RegionsRegions

Figure 1.11b

Abdominopelvic QuadrantsAbdominopelvic Quadrants

Right upperLeft upperRight lowerLeft lower

Figure 1.12

At the clinicAt the clinic

1.This cavity contains the bladder and the rectum.

2.Which body cavity protects the nervous system?

3.The frontal section is also called what?

4.This region is inferior to the lumbar region.

5.This region is superior to the hypogastric region.