Structure C, D, and E in the diagram represent the endoplasmic reticulum, the ribosome, and the Golgi apparatus respectively.
When the ribosomes are attached to the endoplasmic reticulum, they give it a rough appearance.
The ribosome, endoplasmic reticulum, and the Golgi apparatus work together in the synthesis and transport of protein within the cell. In other words, they are all involved in the secretory pathway of cells.
- The ribosome represents the actual site of protein synthesis.
- The endoplasmic reticulum gets involved by folding the synthesized proteins and packaging them into secretory vesicles. Thereafter, the vesicles are transported to the Golgi apparatus.
- The packaged proteins undergo further processing within the Golgi apparatus before they are exported to the cell membrane via the cytosol.
In other words, the 3 organelles work together to form the secretory pathway of the cell. They are involved in the synthesis, packaging, processing, and eventual transport of proteins to their target sites.
More on the secretory pathway can be found here: https://brainly.com/question/4678228
