Epithelium Cells

Introduction

• Epithelium: A type of tissue that covers external and internal surfaces.
• Pseudostratified Epithelium: Appears to be composed of multiple layers but in reality, all cells rest on the basement membrane.

Pseudostratified Epithelium

• Meaning of the word: Pseudo means false and stratified means layered.
• Structure:
  • Crowded cells, some tall reaching the surface (columnar), and some short not reaching the surface.
  • The nuclei are at varying levels giving a false impression of layering.

Types of Pseudostratified Epithelium

Type One: Non-ciliated Pseudostratified Columnar Epithelium

• Location: Found in the male reproductive system, especially in the epididymis.
• Function: Storage of sperm and secretion of a nourishing fluid, helping them gain motility.

Type Two: Ciliated Pseudostratified Columnar Epithelium

• Location: Covers most of the respiratory system (from the nose to the bronchi).
• Components: Contains goblet cells that secrete mucus.
• Function:
  • The cilia move dust-laden mucus out of the respiratory system.
  • The mucus is expelled as phlegm which can be swallowed or spit out.

Conclusion

• Importance of cilia and mucus: Protect the respiratory system from dust and unwanted particles.
• Exam question: There was a question about the type of epithelium covering the respiratory system in the Bachelor of Surgery exam.