8.1: Introduction
- Page ID
- 138423
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Figure \(\PageIndex{1}\): a) diagram of a single goblet cell, showing key components of the endomembrane systems used to synthesize and package the protein, mucin. b) two goblet cells are indicated with black arrows in epithelial tissue. Image source: a) OpenStax College, CC BY 3.0, via Wikimedia Commons, b) OpenStax Anatomy and PhysiologyOpenStax, CC BY 4.0, via Wikimedia Commons
The endomembrane system is a group of structures in cells that work together to make and transport important substances like proteins and lipids. Goblet cells (Figure \(\PageIndex{1}\)), which are found in places like our lungs and intestines, are a great example of how this system works. These cells produce mucus, which helps protect and lubricate surfaces. The process starts in the rough endoplasmic reticulum (RER), where the cell makes mucin proteins. These proteins then move to the Golgi apparatus, where they are modified and packaged into tiny bubbles called vesicles. These vesicles travel to the surface of the goblet cell and release the mucus when needed. This teamwork within the endomembrane system allows goblet cells to effectively produce and secrete mucus, keeping our organs healthy and functioning properly.