Now, by the way, if this is our diagram of the eukaryotic cell, we have the nucleus, we have our rough endoplasmic reticulum that contains these folds. We have slightly smoother, more tubular folds on the smoothie R, and this is our Golgi apparatus. So let's discuss the smoothie R, which is this section here. Now, the smoothie R contains folds that are slightly more tubular than the folds on the rough Er. And this can be seen from this picture here. Now, unlike the rough Er, the smooth Er does not contain ribosomes embedded in the membrane.