body cavities diagram, body cavities illustration, lateral and anterior views

Body Cavities Lesson

Locations, Organization, and Contained Structures

Table of Contents ►

Introduction
Ventral Cavity
Dorsal Cavity
Assessment
Terms of Use
References and Attributions

Introduction

The body contains two major cavities: the dorsal cavity and the ventral cavity. These compartments and their subdivisions house and protect many vital organs, tissues, and associated fluids.

human body cavities diagram, human body cavities illustration, lateral view, labeled

human body cavities diagram, human body cavities illustration, anterior view, labeled

Dorsal Cavity

The dorsal cavity consists of two interconnected chambers, the cranial and vertebral cavities, that protect the central nervous system.

Within the skull is the cranial cavity, the most superior of the body cavities. It contains the brain, which serves as the control center for thoughts, movements, sensations, and other essential processes. The skull’s thick bones provide rigid protection, and cerebrospinal fluid cushions the brain against sudden movements and impacts.

The vertebral or spinal cavity extends along the posterior aspect of the body and houses the spinal cord, the pathway from the brain to the spinal nerves and peripheral organs. This narrow canal extends from the base of the skull to the lower back and is protected by the bones of the vertebral column.

Dorsal Cavity Accordion

Dorsal Cavity Organization

Cranial Cavity

Contents: Brain

Vertebral (Spinal) Cavity

Contents: Spinal cord

Ventral Cavity

The ventral cavity is located on the anterior, or front, side of the body. It is subdivided into the thoracic cavity superiorly and the abdominopelvic cavity inferiorly, each containing multiple organs.

The thoracic cavity occupies the chest region and is protected by the rib cage. Within it are the two pleural cavities, each containing a lung. Between the pleural cavities lies a space called the mediastinum, through which the esophagus, trachea, and major blood vessels pass. Within the mediastinum is the pericardial cavity, which contains the heart.

The diaphragm, a dome-shaped muscle, separates the thoracic cavity from the abdominopelvic cavity below.

The abdominopelvic cavity is subdivided into the abdominal cavity and the pelvic cavity. The abdominal cavity contains most digestive organs, the spleen, and the kidneys. The pelvic cavity contains the urinary bladder, reproductive organs, and the rectum, which is the lower part of the large intestine.

Ventral Cavity Accordion

Ventral Cavity Organization

Thoracic Cavity

Pleural Cavities

Contains: Lungs

Mediastinum

Contains: Esophagus, Trachea, Major Blood Vessels

Pericardial Cavity

Contains: Heart

Diaphragm

Function: Primary Respiratory Muscle

The diaphragm is a dome-shaped muscle that forms the inferior boundary of the thoracic cavity and the superior boundary of the abdominal cavity. When the diaphragm contracts and moves downward, it increases the volume of the thoracic cavity, allowing the lungs to expand and draw in air. This muscle is essential for breathing and serves as the anatomical separator between these two major body cavities.