Download Smooth Endoplasmic Reticulum

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It is a specific type of endoplasmic reticulum,
which surrounds the nucleus.
SER is found in both animal cells and plant
cells.
Unlike RER, it is tubular in form.
Because it lacks ribosomes, it is known as
smooth ER.
Large quantities of certain compounds such
as Phenobarbital cause an increase in the
amount of SER.
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The smooth ER is the site of synthesis of lipids,
including phospholipids, which are major
components of the plasma and internal
membranes.
SER contains enzymes that function in the
synthesis of steroid hormones.
The membranes of SER contain enzymes that
catalyze a series of reactions to detoxify both
lipid-soluble drugs and harmful products of
metabolism, especially in the liver cells.
It functions in the regulation of calcium
concentration, which is important for muscle
contraction.
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The SER represents only a small portion of
ER in most cells, but it is a prominent
constituent in the cells of the adrenal cortex,
and the cells of the liver.
It serves as a transport of proteins
synthesized in the RER to the Golgi
apparatus.
It also contains the enzyme glucose-6phosphatase which is converted to glucose
(This is a step in gluconeogenesis).
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IN A PLANT CELL
IN AN ANIMAL CELL
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