All proteins are synthesized by ribosomes in the cell. Some ribosomes float freely in the cytosol, while others are bound to the surface of the endoplasmic reticulum. Most proteins made by free ribosomes function in the cytosol. Proteins made by bound ribosomes either function within the endomembrane system or pass through it and are secreted from the cell. Which of the following proteins are synthesized by bound ribosomes? Select all that apply.1. actin
2. ER protein
3. ribosomal protein
4. insulin
5. DNA polymerase
6. lysosomal enzyme

2. ER protein

4. insulin

6. lysosomal enzyme

Explanation:

Ribosomes are the organelles which are associated with the synthesis of proteins in the cell as they provide the machinery and site for protein synthesis.

The ribosomes can be freely present in the cytosol or they are presently attached to the endoplasmic reticulum.

The free ribosomes are destined to produce proteins which are required by the same cell like the DNA polymerase enzyme and ribosomal protein but the attached ribosomes produce proteins which have to be transported through the cell-like insulin, and the lysosomal proteins.

Thus, 2,4 and 6 is correct.

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