Which of the following correctly shows the sequence of organelles a protein would take if it were being exported from the cell?
1. Nucleus
2. Endoplasmic reticulum
3. Golgi apparatus
4. Cell membrane
The correct sequence of organelles a protein would take if it were being exported from the cell is as follows:
1. Endoplasmic reticulum (ER): Proteins are synthesized by ribosomes attached to the rough ER, where they undergo modifications and folding.
2. Golgi apparatus: Proteins synthesized by the ER are transported to the Golgi apparatus in transport vesicles. Within the Golgi apparatus, proteins undergo further modifications, such as glycosylation, and are sorted before being packaged into vesicles.
3. Transport vesicles: The Golgi apparatus packages the proteins into transport vesicles, which bud off and move towards the plasma membrane.
4. Plasma membrane: The transport vesicles fuse with the plasma membrane, allowing the proteins to be secreted out of the cell. The protein is now outside the cell, completing the process of export.