An important organelle in the Eukaryota cells is the Endoplasmic Reticulum (ER). It is important for the cells because it plays the key role in the construction, processing, and transport of some proteins and lipids that are necessary for the living body. The ER is responsible for the production of transmembrane proteins and lipids for the cell membrane and also for some important components of the cell including the Golgi apparatus, lysosomes, plant cell vacuoles, secretory vesicles etc.

Structure of the ER

The ER is a nicely organized network of several tubules and compressed sacs.In the ER two distinctive regions could be traced that differ both in function as also structure.

  • Rough ER – In the cytoplasmic side of the membrane in some part of ER ribosome is attached making it a rough side. From outside, it looks like a compact series of flattened sacs.
  • Smooth ER – The other region doesn’t contain any ribosome making it a smooth region. From outside, it looks like a tubular network.

Inside the ER some space could be found which is known as thelumen. The ER is extended from the cell membrane through the cytoplasm to the nuclear envelope.

Rough ER

The rough ER forms secretory proteins and membranes. The attached ribosomes in this part of ER produce proteins by translation.

  • The ER present in certain types of leukocytes or WBC produces antibodies.
  • The rough ER present in the pancreatic cells produces insulin.

Both the rough ER and smooth ER are typically interconnected. The proteins and membranes produced by the rough ER are transferred into the smooth ER that is again transferred to the other locations. Some of these produced proteins are sent to the Golgi apparatus. It is then modified in the Golgi and then transferred to the appropriate destinations within the same cell. The produced Golgi is also exported to the other cells by exocytosis.

Smooth ER

The smooth ER also possesses a wide range of functions like carbohydrate and lipid synthesis. Phospholipids and cholesterol are too important in the construction of cell membranes. Apart from that the smooth ER also helps to transport the ER products that are formed in the rough ER to various other locations.

  • The smooth ER present in the liver cells produce enzymes that supportin the detoxification of certain chemical compounds. Here, it especially helps in the removal of toxic compounds produced from alcohol and medicine intake.
  • In the muscles, the smooth ER helps in the production of calcium ion that in turn triggers contraction of muscle cells.
  • In brain cells, the smooth ER synthesizes hormones.

So, it can be said that the ER is the next major component in the cell apart from the nucleus. Students are given assignments on different topics from the ER. Writing on such assignment topics is not an easy job as the students are bound to complete them within a fixed deadline. BookMyEssay provides expert assistance for completing biology assignment writing task within the deadline.