Where are ribosomes typically located in eukaryotic cells?

Ribosomes in eukaryotic cells are primarily found in two locations: freely suspended in the cytoplasm and attached to the endoplasmic reticulum (ER), specifically the rough ER. This distribution is essential for their function in synthesizing proteins. The ribosomes in the cytoplasm generally synthesize proteins that will function within the cytosol, while those attached to the rough ER are primarily involved in producing proteins destined for secretion or for use in lysosomes and the cell membrane.

The presence of ribosomes on the rough ER gives it a "rough" appearance under a microscope and plays a crucial role in the cellular machinery for protein synthesis. This organization enables efficient processing and transport of newly synthesized proteins.

While ribosomes can also be found in mitochondria, which have their own bacterial-like ribosomes, this is not a common consideration for the location of ribosomes within the typical broader context of eukaryotic cell function. The nucleus and the Golgi complex do not contain ribosomes; rather, the nucleus is involved in RNA synthesis, and the Golgi complex is involved in modifying and sorting proteins synthesized by ribosomes for their final destinations. Thus, the best answer is that ribosomes are typically located in the cytoplasm and attached