Lesson 1 (Part B) Body Planes Vocabulary

Anatomical Body Planes and Sectional Terminology

Anatomical planes are hypothetical flat surfaces used to divide the human body or its organs into specific sections for structural, clinical, and diagnostic visualization.

  • Midsagittal Plane:

    • Defines a vertical plane passing directly through the longitudinal midline of the body.
    • Divides the body into equal right and left halves.
    • Designated by reference letter (D) in Lesson 1 (Part B) Body Planes exercises.

  • Sagittal Plane:

    • Defines any vertical plane parallel to the median longitudinal axis.
    • Divides the body into unequal right and left portions.
    • Designated by reference letter (B) on Page 18 exercises.

  • Horizontal Plane (Transverse Plane):

    • Defines a plane running horizontally across the body perpendicular to its long axis.
    • Divides the body into superior (upper) and inferior (lower) portions.
    • Designated by reference letter (D) on Page 18 exercises.

  • Frontal Plane (Coronal Plane):

    • Defines a vertical plane positioned perpendicular to the sagittal plane.
    • Divides the body into anterior (front) and posterior (back) portions.
    • Represented in standard anatomical classification options alongside sagittal, midsagittal, and horizontal planes.

Abdominopelvic Quadrants

The abdominopelvic cavity is segmented into four distinct quadrants formed by a vertical line and a horizontal line intersecting directly at the umbilicus. This system is primarily utilized in clinical practice to localize internal organ pain, tumors, and anatomical landmarks.

  • Right Upper Quadrant (RUQ):

    • Designated by reference letter (A) on Page 19.
    • Located in the superior right section of the anterior abdominal wall.

  • Left Upper Quadrant (LUQ):

    • Designated by reference letter (C) on Page 19.
    • Located in the superior left section of the anterior abdominal wall.

  • Right Lower Quadrant (RLQ):

    • Designated by reference letter (D) on Page 19.
    • Located in the inferior right section of the anterior abdominal wall.

  • Left Lower Quadrant (LLQ):

    • Designated by reference letter (B) on Page 19.
    • Located in the inferior left section of the anterior abdominal wall.

Regional Subdivisions of the Abdominopelvic Cavity

To facilitate precise clinical and anatomical anatomical localization, the abdominopelvic cavity is subdivided into nine distinct regions using a grid formed by two vertical lines (midclavicular lines) and two horizontal lines (subcostal and transtubercular planes).

  • Epigastric Region:

    • Designated by reference key (80) / (B) on Page 20.
    • Located superiorly in the middle column, directly above the umbilical region and superior to the stomach.

  • Umbilical Region:

    • Designated by reference key (E) on Page 20.
    • Located centrally within the nine-region grid, surrounding the navel (umbilicus).

  • Hypogastric Region (Pubic Region):

    • Designated by reference key (H) on Page 20.
    • Located inferiorly in the middle column, situated below the umbilical region.

  • Right Hypochondriac Region:

    • Designated by reference key (A) on Page 20.
    • Located superiorly on the right lateral side relative to the epigastric region, beneath the cartilage of the ribs.

  • Left Hypochondriac Region:

    • Designated by reference key (A) / (G) on Page 20.
    • Located superiorly on the left lateral side relative to the epigastric region, beneath the rib cartilage.

  • Right Lumbar Region:

    • Designated by reference key (D) on Page 20.
    • Located laterally on the right side between the right hypochondriac and right iliac regions.

  • Left Lumbar Region:

    • Designated by reference key () / (F) on Page 20.
    • Located laterally on the left side between the left hypochondriac and left iliac regions.

  • Right Iliac Region (Right Inguinal Region):

    • Designated by reference key (C) on Page 20.
    • Located inferiorly on the right side lateral to the hypogastric region near the groin.

  • Left Iliac Region (Left Inguinal Region):

    • Designated by reference key (I) on Page 20.
    • Located inferiorly on the left side lateral to the hypogastric region near the groin.

Major Body Cavities and Structural Subdivisions

Body cavities are internal spaces within the body that house, protect, and support visceral organs. They are divided into two main cavities: the dorsal body cavity and the ventral body cavity.

  • Dorsal Body Cavity:

    • Designated by reference letter (E) on Page 21.
    • Located along the posterior surface of the body.
    • Houses the cranial cavity (containing the brain) and the spinal/vertebral cavity (containing the spinal cord).

  • Ventral Body Cavity:

    • Designated by reference letter (F) on Page 21.
    • Located along the anterior surface of the body.
    • Houses thoracic and abdominopelvic internal cavities separated by the diaphragm muscle.

  • Thoracic Cavity:

    • Designated by reference letter (C) on Page 21.
    • Enclosed superiorly by the ribs, sternum, and chest muscles.
    • Houses the lungs (pleural cavities) and heart (pericardial cavity within the mediastinum).

  • Abdominopelvic Cavity:

    • Designated by reference letter (D) on Page 21.
    • Extends from the diaphragm inferiorly to the pelvic floor.
    • Represents the continuous space composed of both abdominal and pelvic cavities.

  • Abdominal Cavity:

    • Designated by reference letter (B) on Page 21.
    • Superior subdivision of the abdominopelvic cavity.
    • Contains primary digestive viscera including the stomach, liver, gallbladder, spleen, pancreas, small intestine, and majority of the large intestine.

  • Pelvic Cavity:

    • Designated by reference letter (A) on Page 21.
    • Inferior subdivision of the abdominopelvic cavity enclosed by pelvic bones.
    • Contains internal reproductive organs, the urinary bladder, and the rectum.

Academic Worksheet Key and Structural Summary

  • Participant Context Record:

    • Associated name identifier: christelle.
    • Curricular module title: Lesson 1 (Part B)-Worksheet.

  • Page Organization and Section Mapping:

    • Page 18: Body Planes worksheet covering midsagittal, sagittal, frontal, and horizontal plane identifications.
    • Page 19: Abdominopelvic Quadrants mapping right upper quadrant (A), left upper quadrant (C), right lower quadrant (D), and left lower quadrant (B).
    • Page 20: Regional Subdivisions of the Abdominopelvic Cavity mapping nine regional anatomical sections (A, B/80, C, D, E, F, G, H, I).
    • Page 21: Body Cavities labeling pelvic cavity (A), abdominal cavity (B), thoracic cavity (C), abdominopelvic cavity (D), dorsal cavity (E), and ventral cavity (F).