Endomembrane System

Front

What is the endomembrane system?

Back

A network of membranes within a cell that includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles, involved in the synthesis, modification, and transport of proteins and lipids.

Front

What is the function of lysosomes?

Back

Lysosomes are organelles that contain digestive enzymes to break down waste materials and cellular debris.

Front

What is the role of the rough endoplasmic reticulum (RER)?

Back

The RER is involved in the synthesis of proteins that are either secreted from the cell, incorporated into the cell's plasma membrane, or sent to an organelle.

Front

What gives the rough endoplasmic reticulum its rough appearance?

Back

The rough appearance is due to the presence of ribosomes attached to its cytoplasmic surface.

Front

What is the function of ribosomes?

Back

Ribosomes are the sites of protein synthesis in the cell, translating messenger RNA (mRNA) into polypeptide chains.

Front

What is the function of the Golgi apparatus?

Back

The Golgi apparatus modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

Front

How do secretory vesicles function in the endomembrane system?

Back

Secretory vesicles transport proteins and lipids from the Golgi apparatus to the plasma membrane for secretion.

Front

What is the difference between smooth and rough endoplasmic reticulum?

Back

The rough endoplasmic reticulum has ribosomes on its surface and is involved in protein synthesis, while the smooth endoplasmic reticulum lacks ribosomes and is involved in lipid synthesis and detoxification.

Front

What is the role of the nuclear envelope in the endomembrane system?

Back

The nuclear envelope is a double membrane that encloses the nucleus, separating its contents from the cytoplasm and regulating the passage of materials in and out of the nucleus.

Front

What happens to proteins after they are synthesized in the rough endoplasmic reticulum?

Back

After synthesis, proteins are folded and modified in the RER, then transported to the Golgi apparatus for further processing.