Do eukaryotic cells have a endoplasmic reticulum?
Yes. They have both a rough and smooth endoplasmic reticulum.
The endoplasmic reticulum is an eukaryotic organelle that form a network of interconnected tubules, vesicle, and cisternae within cells. The rough endoplasmic reticulum synthesizes proteins. Smooth endoplasmic reticulum synthesizes lipids, steroids, metabolizes carbohydrates, and regulates calcium concentration.
Why do ribosomes float freely in cytoplasm and why are they also attached to the rough endoplasmic reticulum?
Ribosomes are found in prokaryotic and eukaryotic cells. They are present in mitochondria, chloroplasts and bacteria. The ribosomes found in prokaryotes are smaller in size and are found floating in the cytoplasm of the cell. In eukaryotes ribosomes are associated with the endoplasmic reticulum to form the rough endoplasmic reticulum.