Question

order the steps from the source to the target in the order that occurs as a protein is synthesized within a cell and finally excreted for use outside of the cell.
be sure that the earliest step is placed at the top.
source \t\t\t\t\t\ttarget
rough er
cell membrane
nucleus
mrna
ribosome
golgi body

Explanation:

This is the sequential pathway of protein synthesis and secretion:

1. The gene for the protein is transcribed into mRNA in the nucleus.
2. mRNA exits the nucleus and binds to a ribosome.
3. Ribosomes attached to the rough ER synthesize the protein, which enters the ER lumen.
4. Vesicles carry the protein from the rough ER to the Golgi body for processing.
5. Processed proteins are packaged into vesicles that fuse with the cell membrane.
6. The protein is released (excreted) outside the cell via exocytosis.

Answer:

1. Nucleus
2. mRNA
3. Ribosome
4. Rough ER
5. Golgi Body
6. Cell Membrane