What is the endomembrane system of the cell?
Posted April 2, 2021
Answer
The endomembrane system, which is present in eukaryotic cells, is a collection of membranes and organelles that work communally to modify, sort, package and transport proteins and lipids. It consists of the following organelles:
- Nuclear membrane – consists of two lipid bilayer membranes, embedded with proteins, that surrounds the nucleus and protects its genetic material.
- Endoplasmic reticulum – is an organelle made up of two subunits, a smooth and rough endoplasmic reticulum. It is responsible for synthesizing lipids and proteins.
- Golgi apparatus – is an organelle consisting of multiple cisternal stacks that is responsible for modifying, packaging and transporting proteins and lipid molecules.
- Lysosomes – an organelle containing digestive enzymes for digesting macromolecules, old cell parts, microorganisms, etc.
- Endosomes – sorting organelles that originate from the trans-Golgi network and are part of the endocytic membrane transport pathway.
- Vesicles – a small enclosed lipid bilayer containing cytoplasm and materials for transport.
- Plasma membrane – lipid bilayer that encompasses all of the cells components and separates the interior of the cell from the outside environment. All the aforementioned organelles are housed within the plasma membrane.
Additional resources
A Multi-Functional Tubulovesicular Network as the Ancestral Eukaryotic Endomembrane System