Question

Arrange the following in the correct sequence: 1. Polypeptide chaines move through the rough ER and are then carried in vesicles to the Golgi apparatus. 2. Vesicles are pinched off from the Golgi apparatus carrying newly formed proteins to the plasma membrane. 3. The Golgi apparatus separates and modifies varieties of proteins and then packages them into vesicles. 4. Polypeptide chains are made by ribosomes on the rough ER.

Answer 1

The answer is;

4, 1, 3, 2

The rough endoplasmic reticulum (RER) is referred to as ‘rough’ due to the presence of numerous ribosomes on its membrane. When the ribosomes translate proteins, the proteins enter the lumen of the ER and are folded appropriately by the help of chaperones. The proteins travel from the cis to the trans end of the ER during this modification this process. At the trans end they pinch off into vesicle that later join the Golgi apparatus. The protein are modified and packaged in teh Golgi. They then pinch off into vesicles and transported to their site in the cell or to the plasma membrane for exocytosis.