Question

Ribosomes in animal and plant cell are located
A) Inside the nucleus
B) Near the cell membrane
C) On the endoplasmic reticulum
D) Inside the vacuole

Answer 1

Hint:Ribosomes are cell organelles which play an important role in the mechanism for protein synthesis. This organelle provides a platform for the mRNA to adhere to so that the tRNAs can facilitate the attachment of amino acids to the peptide chain.

Complete answer:
Ribosomes are cell organelles responsible for the generation of proteins from the genetic content encoded in the nucleic acids. This process always takes place inside the cytoplasm of the cell. In eukaryotes, sometimes the protein generated is to be transported to other regions of the cell or outside the cell body, the ribosomes attached to the endoplasmic reticulum (cell organelle which forms a canal for the transport of molecules across the cell membrane) facilitate the process of translation.

Now, let us look at each option one by one.
>The process of translation occurs in the cytoplasm due to the presence of ribosomes. The nucleus does not contain any ribosomes in it. Therefore, this option is incorrect.
>Near the cell membrane, exchange of molecules across the membrane via diffusion or by specialized channels occurs. Ribosomes are not seen in this region. Therefore, this option is incorrect.
>As mentioned earlier, eukaryotic cells have ribosomes attached to the surface of the endoplasmic reticulum which allows for easy transport of the protein synthesized across as well as outside the cell. Therefore, this is the correct option.
>The vacuole is an organelle which is mainly responsible for the digestion of food ingested by the cell. The process of translation cannot occur inside the vacuole due to the presence of harsh hydrolytic enzymes encapsulated within it. Therefore, this option is incorrect.

Thus, the correct answer is option (C) On the Endoplasmic reticulum.

Note:In prokaryotic cells, unlike the eukaryotic cells, ribosomes are freely dispersed within the cell’s cytoplasm. Since these cells are very primitive in nature, membrane bound organelles do not exist, as a result the nucleus as well as the ribosomes are found freely floating in the cytoplasm.