Anatomical Terminology: Foundations for Anatomy & Physiology

Anatomical Terminology

Introduction to Anatomical Terminology

Anatomical terminology provides a standardized language for describing the locations, positions, and relationships of body structures. Mastery of these terms is essential for clear communication in anatomy and physiology.

• Anatomy: The study of the structure of the body and its parts.

• Suffix -ical: Means "pertaining to" (e.g., anatomical = pertaining to anatomy).

Medical Word Parts

Common Suffixes and Prefixes

Understanding common suffixes and prefixes helps in interpreting medical terms.

Suffix	Meaning
-ac	Pertaining to
-al	Pertaining to
-ar	Pertaining to
-iac	Pertaining to
-ic	Pertaining to
-ior	Pertaining to

Prefix	Meaning
ante-	Before, in front of
epi-	Above
hypo-	Below, insufficient
retro-	Behind

Anatomical Combining Forms

Key Combining Forms and Their Meanings

Combining forms are used to construct medical terms related to body regions and structures.

Combining Form	Definition	Combining Form	Definition
abdomin/o	Abdomen	dist/o	Away from (beginning of structure)
anter/o	Front (side of body)	dors/o	Back (side of body)
brachi/o	Arm	femor/o	Femur (thigh bone)
caud/o	Tail	gastr/o	Stomach
cephal/o	Head	genit/o	Genitals
cervic/o	Neck	glute/o	Buttocks
chondr/o	Cartilage	ili/o	Ilium (part of pelvis)
crani/o	Skull	infer/o	Below
cubital/o	Elbow	inguin/o	Groin
later/o	Side	poster/o	Back (side of body)
lumb/o	Low back	proxim/o	Near to (beginning of structure)
medi/o	Middle	scapul/o	Scapula (shoulder blade)
nas/o	Nose	spin/o	Spine
or/o	Mouth	stern/o	Sternum (breast bone)
orbit/o	Eye socket	super/o	Above
ot/o	Ear	thorac/o	Chest
patell/o	Patella (kneecap)	ventr/o	Belly (side of body)
pelv/o	Pelvis	vertebr/o	Vertebra (backbone)

Anatomical Position

Definition and Importance

The anatomical position is a standardized reference point used to describe the location of body structures. It is defined as:

• Standing upright

• Legs together, feet forward: Feet are parallel and flat on the ground.

• Arms at the sides, palms forward, fingers extended: Arms are extended downward at the sides of the body with the palms facing forward.

• Eyes straight ahead: Head and eyes are directed straight ahead.

This position ensures consistency when describing anatomical structures and their relationships.

Body Planes and Sections

Major Anatomical Planes

The human body can be divided into sections using three primary planes:

• Frontal (Coronal) Plane: Divides the body into anterior (front) and posterior (back) portions. A cut along this plane produces a frontal section.

• Sagittal Plane: Divides the body into right and left portions. A cut along this plane produces a sagittal section. The midsagittal plane runs down the midline, dividing the body into equal right and left halves.

• Transverse Plane: Divides the body into superior (upper) and inferior (lower) portions. A cut along this plane produces a transverse (cross) section.

Additional info: Longitudinal sections are produced by cuts along the long axis of a structure, while cross-sections are produced by cuts perpendicular to the long axis.

Directional Terminology

Describing Locations and Relationships

Directional terms specify the position of one structure relative to another. They often come in pairs with opposite meanings.

• Superior (cranial): Above another structure.

• Inferior (caudal): Below another structure.

• Anterior (ventral): Toward the front of the body.

• Posterior (dorsal): Toward the back of the body.

• Medial: Toward the midline of the body.

• Lateral: Away from the midline of the body.

• Proximal: Nearer to the point of attachment or origin.

• Distal: Farther from the point of attachment or origin.

• Superficial: Nearer the surface of the body.

• Deep: Further below the surface.

• Prone: Lying face down.

• Supine: Lying face up.

Example: The heart is superior to the stomach; the stomach is inferior to the heart.

Body Surface Terminology

Terms for Body Regions

Specific terms are used to refer to various body surface regions.

Word Root	Meaning
abdomin/o	Pertaining to the abdomen
brachi/o	Pertaining to the arm
cervic/o	Pertaining to the neck
crani/o	Pertaining to the skull
cubital (ante-)	Pertaining to the front of the elbow
femor/o	Pertaining to the femur/thigh
genit/o	Pertaining to the genitals
glute/o	Pertaining to the buttocks
inguin/o	Pertaining to the groin
nas/o	Pertaining to the nose
orbit/o	Pertaining to the eye socket
or/o	Pertaining to the mouth
ot/o	Pertaining to the ear
patell/o	Pertaining to the kneecap
pelv/o	Pertaining to the pelvis
scapul/o	Pertaining to the shoulder blade
stern/o	Pertaining to the breast bone
thorac/o	Pertaining to the chest
vertebr/o	Pertaining to the vertebrae/backbone

• Axillary: Underarm area

• Palmar: Palm of the hand

• Plantar: Sole of the foot

• Popliteal: Back of the knee

• Trunk: Torso

• Umbilical: Navel area

• Upper extremity: Entire arm

• Lower extremity: Entire leg

Body Cavities

Major Body Cavities and Their Contents

The body contains several major cavities that house internal organs. These are divided into dorsal and ventral cavities.

• Dorsal Cavities:

  • Cranial cavity: Located within the skull; contains the brain, protected by the meninges.

  • Spinal cavity: Formed by the vertebral canal; contains the spinal cord, also protected by the meninges.

• Ventral Cavities:

  • Thoracic cavity: Enclosed by the ribs and separated from the abdominopelvic cavity by the diaphragm. Contains:

    • Mediastinum: Central region containing the heart, trachea, esophagus, and thymus gland.

    • Pleural cavities: Each contains a lung.

  • Abdominopelvic cavity: Inferior to the diaphragm; contains:

    • Abdominal cavity: Stomach, liver, gallbladder, spleen, pancreas, small intestine, most of the large intestine.

    • Pelvic cavity: Urinary bladder, ureters, urethra, and reproductive organs. Kidneys are retroperitoneal (behind the peritoneum).

Divisions of the Abdominopelvic Cavity

Clinical and Anatomical Divisions

The abdominopelvic cavity can be divided for descriptive and diagnostic purposes.

• Clinical Divisions (Quadrants): The cavity is divided into four quadrants:

  • Right Upper Quadrant (RUQ): Contains part of the liver, right kidney, right ureter, pancreas, gallbladder, and portions of the intestines.

  • Right Lower Quadrant (RLQ): Contains right ureter, portions of intestines, appendix, and right reproductive structures.

  • Left Upper Quadrant (LUQ): Contains stomach, spleen, part of the liver, pancreas, left kidney, left ureter, and portions of the intestines.

  • Left Lower Quadrant (LLQ): Contains left ureter, portions of intestines, sigmoid colon, left reproductive structures, urinary bladder, and rectum.

• Anatomical Divisions (Regions): The cavity can also be divided into nine regions for more precise localization (not fully detailed in the provided content).

Example: To examine the hypochondriac region, a healthcare provider palpates the upper lateral area of the abdomen.

Additional Information

• Military Time Table: Used in medical settings for clarity in documentation. (See table below.)

Normal Time	Military Time	Normal Time	Military Time
12:00 AM	0000	12:00 PM	1200
1:00 AM	0100	1:00 PM	1300
2:00 AM	0200	2:00 PM	1400
3:00 AM	0300	3:00 PM	1500
4:00 AM	0400	4:00 PM	1600
5:00 AM	0500	5:00 PM	1700
6:00 AM	0600	6:00 PM	1800
7:00 AM	0700	7:00 PM	1900
8:00 AM	0800	8:00 PM	2000
9:00 AM	0900	9:00 PM	2100
10:00 AM	1000	10:00 PM	2200
11:00 AM	1100	11:00 PM	2300