28. Describe the structure and function of the endoplasmic reticulum (both rough ER and smooth ER). 29. Describe the structure and function of the Golgi apparatus
i think the golgi apparatus packages proteins
There are rough ER and smooth ER. They both have the same types of membranes but they have different shapes and rough ER has ribosomes attached. Rough ER looks like sheets of bumpy membranes while smooth ER looks more like tubes. Sometimes the ER looks like a flat balloon. Smooth ER has its purpose in the cell. It acts as a storage organelle. It is important in the creation and storage of steroids. It also stores ions in solution that the cell may need at a later time. Steroids are a type of ringed organic molecule used for many purposes in an organism. They are not always about building muscle mass like a weight lifter. The ion storage is important because sometimes a cell needs ions fast. It might not want to search the environment for ions, so it is easier to have them stored in a pack for easy use.Rough ER was mentioned in the section on ribosomes. They are very important in the synthesis and packaging of proteins. Some of those proteins might be used in the cell and some are sent out. The ribosomes are attached to the membrane of the ER. As the ribosome builds the amino acid chain, the chain is pushed into the ER. When the protein is complete, the rough ER pinches off a vesicle. That vesicle, a small membrane bubble, can move to the cell membrane or the Golgi apparatus.
@Phebe
A major organelle in most eukaryotic cells is the structure of membrane-bound sacs called the Golgi apparatus (or Golgi body, Golgi complex, dictyosome). It acts to process and package the macromolecules such as proteins and lipids that are synthesized by the cell. It has been likened to the cell's post office. A major function is the modifying, sorting and packaging of proteins for secretion. It is also involved in the transport of lipids around the cell, and the creation of lysosomes. The sacs or folds of the Golgi apparatus are called cisternae. Typically there are five to eight cisternae but as many as sixty have been observed. The cisternae stack has five functional regions: the cis-Golgi network, cis-Golgi, medial-Golgi, trans-Golgi, and trans-Golgi network. Vesicles from the endoplasmic reticulum fuse with the cis-Golgi network and subsequently progress through the stack to the trans-Golgi network, where they are packaged and sent to the required destination. Each region contains different enzymes which selectively modify the contents depending on where they are destined to reside. This is for the second one.
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