Question

How do smooth endoplasmic reticulum function?

Answer 1

Hint: The smooth endoplasmic reticulum is a membrane bound organelle and is found in eukaryotic cells. The smooth Endoplasmic reticulum does not possess any membrane-bound ribosomes. Smooth Endoplasmic reticulum is made up of a network of tubules called cisternae.

Complete answer:
The smooth endoplasmic reticulum is made of polygonal networks of tubules called cisternae. The smooth ER is a dynamic structure. In smooth Endoplasmic reticulum new tubules bud off from the sides of existing structures. Smooth ER plays an important role in muscle cells and neurons.

The presence of an ER network along the neuron is related to its interaction with actin and microtubules and the smooth ER forms a continuous network across the entire cell.
Smooth ER is associated with dendritic spines, axon, and the synapse.
Smooth ER is mostly allied with mitochondria at the synapse.

ER tubules undergo many morphological changes, on the depolymerization of cytoskeleton.
Although the association amid mitochondria and smooth ER remains intact.
In muscle cells, the smooth endoplasmic reticulum helps in the storage of calcium ions.

Functions of the Smooth Endoplasmic Reticulum
The smooth ER is involved in the synthesis of lipids (such as cholesterol and phospholipids) which in turn help in the formation of the membranes of the organism.
Smooth ER is also involved in carbohydrate metabolism; The final reaction of gluconeogenesis occurs in the lumen of the smooth ER. Lumen of smooth ER contains the enzyme glucose-6-phosphatase.
Glucose-6-phosphatase is the enzyme that catalyzes the formation of glucose from glucose-6-phosphate.

Since smooth endoplasmic reticulum is dynamic in nature so it plays an important role in the liver to detoxify a number of substances and to easily remove them from the body.
For example, during sudden and drastic increase in the quantity of lipid soluble drugs in the body, the smooth ER of liver cells metabolize them to water-soluble compounds. As a result these water soluble compounds are excreted in the urine. In this process a group of a hepatocyte in a smooth ER doubles in size and then comes back to its initial shape and size after the neutralization of chemical attack.

Note: Smooth ER is an integral part of the liver cells. Since smooth endoplasmic reticulum is dynamic in nature so it plays an important role in the liver to detoxify a number of substances and to easily remove them from the body.