Body Cavities Lecture Notes

Introduction

• The human body is not a solid mass; it contains important spaces or cavities.
• Cavities can be external (e.g., nasal cavity) or internal.

Functions of Body Cavities

1. Protection:
   • Protect delicate organs like the brain from bumps and shocks.
2. Flexibility:
   • Allow organs to change shape and size (e.g., lungs, stomach, bladder).
3. Science Fiction Reference:
   • Provide space for foreign organisms to implant (like in alien movies).

Main Body Cavities

1. Dorsal Body Cavity:

   • Cranial Cavity:
     • Formed by the skull bones.
     • Contains the brain.
   • Spinal Cavity (Vertebral Canal):
     • Formed by the vertebral column.
     • Contains the spinal cord.

2. Ventral Body Cavity:

   • Separated by the diaphragm into:
     • Superior Thoracic Cavity
     • Inferior Abdominopelvic Cavity

Thoracic Cavity

• Pleural Cavities:
  • Contains the lungs.
• Pericardial Cavity:
  • Contains the heart.
• Mediastinum:
  • A partition separating the cavities.

Abdominopelvic Cavity

• Abdominal Cavity:
  • Contains the stomach, liver, spleen, kidneys, small intestine, and most of the large intestine.
• Pelvic Cavity:
  • Contains the bladder and internal reproductive organs.

Conclusion

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