What does the Endosplasmic retriculum look like?

The endoplasmic reticulum (ER) is a complex network of membranous tubules and sacs called cisternae. It can be divided into two types: rough ER, which is studded with ribosomes giving it a textured appearance, and smooth ER, which lacks ribosomes and has a more tubular structure. Overall, the ER has a folded, expansive structure that resembles a series of interconnected channels and membranes within the cell. Its appearance can vary depending on the cell type and the functional state of the ER.