Download Smooth ER

Smooth ER
Definiton: Type of organelle in the cells of eukaryotic organisms that
forms flattened, membrane-enclosed sacs or tubes known as cisternae.
The membranes are continuous with the outer membrane of the
nuclear envelope.
Structure of the SER
What's your functions?
• The endoplasmic reticulum is composed of a network of smooth tubules and saclike structures.
• Smooth endoplasmic reticulum does not have ribosomes attached to its surface.
• Extensive system of interconnected tubules and cisternae (flattened sac-like
structures).
• Can be found in almost all eukaryotic cells, excepting red blood cells of mammals.
Functions of the Parts
• Carbohydrate and Lipid Synthesis
• produces cholesterol and membrane phospholipids, which are used for membrane formation.
• metabolism
• Transportation of Proteins
• It regulates the transportation of proteins by acting as a transitional area for vesicles that transfer proteins to various
locations.
• transports the products of RER to Golgi apparatus and other parts of the cell.
• Detoxification
• Drug detoxification, as well as detoxification of wastes generated in metabolic processes takes place in SER present in
the liver cells.
• contains enzymes that catalyze a number of reactions that can make lipid-soluble drugs and metabolic wastes watersoluble, so that they can be easily expelled from the body.
• Other Important Functions
• provides surface area for the action and storage of enzymes and their products
• attaches receptors to cell membrane proteins
• stores calcium in the muscle cells
Structure of the SER
Alzheimer's disease caused by Smooth ER?
• Previous evidence suggests that the increase in platelet membrane fluidity associated with a subgroup of
patients with Alzheimer's disease rA statistically significant change in enzyme activity was observed only for
antimycin A-insensitive NADH-cytochrome reductase, a selective marker for smooth endoplasmic reticulum
(SER) in platelets.
• Reduction was limited to the subgroup of demented patients who had increased platelet membrane fluidity,
and therefore is not a nonspecific concomitant of neurodegeneration, medication exposure, or chronic
illness in general.
• Since the platelet membrane alteration associated with Alzheimer's disease results from the inheritance of a
single major locus, these results suggest that a defect in SER function may exist in brain cells as well as
peripheral cells that express this genotypeesults from the accumulation of internal membrane.
Would you like a Study
Method?
• Flash cards
• Read this power point
• Read from Book