After the amino acid chain leaves the ribosome, which organelle then folds, modifies, and transports the protein?
Ribosome
Lysosome
Endoplasmic reticulum
Cytoplasm
Endoplasmic reticulum.
After the amino acid chain leaves the ribosome, the organelle that then folds, modifies, and transports the protein is the endoplasmic reticulum.
After the amino acid chain leaves the ribosome, it is directed to the endoplasmic reticulum (ER) for further processing. The organelle that folds, modifies, and transports the protein is the endoplasmic reticulum. To understand this information, we can break down the components and functions of each organelle mentioned:
1. Ribosome: Ribosomes are responsible for protein synthesis. They assemble amino acids into chains called polypeptides based on the instructions provided by the DNA messenger RNA (mRNA). The ribosome is located in the cytoplasm.
2. Lysosome: Lysosomes are small vesicles containing enzymes that are involved in cellular digestion. They break down waste materials, cellular debris, and foreign substances. However, lysosomes are not directly involved in folding, modifying, or transporting proteins.
3. Endoplasmic reticulum: The endoplasmic reticulum is a network of membrane-bound sacs and tubes present in eukaryotic cells. It is divided into two types: rough endoplasmic reticulum (RER) and smooth endoplasmic reticulum (SER).
- Rough endoplasmic reticulum (RER): The RER is studded with ribosomes on its surface. Once the amino acid chain is synthesized by the ribosomes, it is directed towards the RER for further processing. The RER is involved in protein folding, modification, and initial sorting. It facilitates the addition of sugars (glycosylation) and helps in forming the proper protein conformation.
- Smooth endoplasmic reticulum (SER): The SER lacks ribosomes on its surface and is involved in lipid metabolism, detoxification, and calcium storage. It does not play a direct role in protein folding, modification, or transport.
4. Cytoplasm: The cytoplasm is the gel-like substance that fills the interior of the cell. While the ribosome is located in the cytoplasm and initiates protein synthesis, it does not carry out the folding, modifying, or transporting processes.
Therefore, the correct organelle that folds, modifies, and transports the protein after it leaves the ribosome is the endoplasmic reticulum.