Hello, thanks for visiting our page. Below you will find detailed information on the subject of the endoplasmic reticulum and the golgi complex. These are two very important organelles that are members of the cytomembrane system. We hope that you find the information that you need below.

ENDOPLASMIC RETICULUM

The endoplasmic reticulum, also commonly known as ER, is the first step in the cytomembrane system. In animal cells, the ER begins at the nucleus and stretches throughout the cytoplasm.
In plants, it also connects between cells via the plasmodesmata.

The ER is divided into two categories, rough and smooth. The difference between the two is the presence or absence of ribosomes.

ROUGH ER

The rough endoplasmic reticulum resembles stacked and flattened sacs. The ribosomes that are attached to the rough ER produce proteins. These new chains have a "signal" which allows the polypeptides to enter the ER (rough & membrane). This "signal" consists of 10 to 15 amino
acids linked together. When the proteins enter the rough ER, they are bonded to oligosaccharides and other side chains. Special cells within the rough ER secrete the final result into the smooth ER. An example of a special cell are the glandular cells produced in the pancreas.

SMOOTH ER

The texture of the smooth ER is more tubular compared to the rough ER because it lacks ribosomes. The smooth ER is the main site for lipid and steroid synthesis. This organelle also aids in the deactivation of certain poisonous metabolic by-products and drugs. An example of these products is carcinogens. The smooth ER converts these chemicals into water-soluble products that can be excreted with bodily waste. Cells that contain large amounts of smooth ER are usually located in the liver and kidneys. Smooth ER is also used in membranes.

THE GOLGI  COMPLEX

The Golgi complex (aka the Golgi body or Golgi apparatus) was named after Camillo Golgi, who first stained and described the organelle in 1898. In many cells the golgi consists of stacks of flattened membranous sacs, which may be distended in certain regions because they are filled with celluar products. It is found in both plant and animal cells.

Unlike the ER the flattened sacs are not continuous, and they contain a number of separate compartments. It functions primarily as an apparatus for processing, sorting and modifying proteins. Most proteins that the Golgi processes are secreted from the cell and become part of the plasma membrane or go to other organelles.

Proteins that travel from the rough ER to the Golgi are in vesicles.  As they pass through the Golgi body they are modified in different ways which form complex biological molecules.  The Golgi also makes glycoproteins.  Scientists guess that glycoproteins are used to aid in sorting carbohydrates to other organelles.  In plant cells the Golgi also produces proteins that are used in the cell wall.

 Works Cited and Links

Images of the ER and the Golgi

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