Why called Smooth Endoplasmic Reticulum?
The smooth ER is not associated with ribosomes and is
involved in lipid metabolism; that is why called “smooth.” Smooth Endoplasmic
Reticulum (SER), is primarily made up of interconnected tubules enclosing a
single internal space called the ER lumen or the ER cisternal space. The SER tubules provide a large
surface area for enzymes and proteins involved in various cellular processes.
In the last post we discussed the structure and function of the RER.
.jpg "5 Functions of SER (Smooth Endoplasmic Reticulum)")
1.Lipid Synthesis
Smooth Endoplasmic Reticulum (SER) is involved in lipid
metabolism is also in continuous connection with RER. SER synthesizes membrane
lipids, including phospholipids and cholesterol
2.Steroid Hormone Synthesis:
SER in steroid producing cells like Leydig cells, granulosa
cells etc is responsible for the synthesis of steroid hormones, such as
testosterone, estrogen, and cortisol. These hormones play important roles in a
variety of physiological processes, including reproduction, metabolism, and
stress response.
3.Drug detoxification
SER is abundant in liver where it detoxified drugs, toxins and other harmful substances. It breaks down these substances into water-soluble forms that can be easily eliminated from the body.
4.Calcium ion storage and regulation: The SER plays a crucial role in
regulating calcium ion (Ca2+) levels in the cytoplasm. It stores Ca2+ ions and
releases them when needed for muscle contraction, nerve signal transmission,
and other cellular processes.
5.Carbohydrate metabolism: SER is involved in the metabolism of carbohydrates,
such as glucose primarily in liver cells or hepatocytes. It can release or
store glucose molecules depending on the cell's needs.
Understand the functions of RER here.