History of Golgi Apparatus:
Italian cytologist Camillo Golgi first observed the Golgi apparatus in 1897. Golgi developed the Golgi stain, commonly known as the reazione era, during his early research on nerve tissue. Using this method, silver nitrate is first diffused into fixed potassium dichromate-fixed nerve tissue. While examining neurons that Golgi dyed with his method, he identified an “internal reticular apparatus.” black reaction. Although some scientists questioned the validity of the structure and explained the discovery as free-floating Golgi metal stain particles, this structure eventually came to be known as the Golgi body. However, the Golgi apparatus was verified in the 1950s when the electron microscope was put to use.
What is the Golgi Apparatus?
The Golgi body sometimes referred to as the Golgi complex or the Golgi body, is a membrane-bound organelle found in eukaryotic cells (cells with clearly defined nuclei). It is composed of several flattened, stacked pouches known as cisternae. For the purpose of delivering proteins and lipids to specific locations, the Golgi bodies move, alter, and pack these substances into vesicles. The endoplasmic reticulum and the cell nucleus are both nearby and are situated in the cytoplasm.
Unlike plant cells, which can have hundreds, many other types of cells only have one or a few Golgi bodies. Cell membrane proteins, lysosomal proteins, secretory proteins, glycoproteins, and certain glycolipids all go through the Golgi bodies throughout the maturation process. The Golgi also receives a large portion of the cell wall constituents in plant cells.
Where is the Golgi Apparatus located?
The endoplasmic reticulum and the cell membrane are separated by the Golgi apparatus. Most frequently, the endoplasmic reticulum, which is slightly smaller and smoother in appearance, looks to be an extension of the Golgi. The smooth endoplasmic reticulum can be confused for the Golgi apparatus, though. Despite having a similar appearance, the Golgi is a separate organelle with distinct activities.
Explain the structure of the Golgi Apparatus.
The “cis” face and the “trans” face of the Golgi apparatus are separated by three main compartments, which are structurally polarized. These faces differ biochemically, and each segment’s enzyme composition is noticeably different. Generally speaking, the cis face membranes are thinner than the others. The Golgi bodies typically consist of four to eight cisternae, but in some single-celled species, they can have up to 60 cisternae.
The cisternae are held together by matrix proteins, while cytoplasmic microtubules sustain the Golgi complex. Cisternae closest to the endoplasmic reticulum is referred to as “cis,” “medial” cisternae (central layers of cisternae), and “trans” respectively, as are the three main compartments of the apparatus (cisternae farthest from the endoplasmic reticulum). The crucial role of sorting proteins and lipids that are received (at the cis face) or discharged (at the trans face) by the organelle is carried out by two networks, the cis Golgi network and the trans-Golgi network, which are composed of the outermost cisternae at the cis and trans faces.
Explain the function of the Golgi apparatus.
The functions of Golgi apparatus include protein secretion and packaging. Proteins are delivered to it via the endoplasmic reticulum. It puts it in membrane-bound vesicles and transports them to other locations, like lysosomes, the plasma membrane, or secretion. Additionally, they participate in the development of lysosomes and lipid transport.
- In Golgi bodies, post translational modifications and enzymatic processing, such as glycosylation and phosphorylation, take place close to the membrane surface.
- The Golgi apparatus is where different glycolipids, sphingomyelin, etc. are produced.
- The Golgi apparatus in plant cells is where complex polysaccharides for the cell wall are synthesized.
- For additional information on the Golgi bodies and other cellular organelles,
The endoplasmic reticulum delivers proteins and lipids to the Golgi complex, where they are altered. Exocytosis is the process by which these biochemicals leave the Golgi and are transported to various intracellular or extracellular destinations.
Protein processing: Glycoproteins’ carbohydrate sections are changed by adding, subtracting, or modifying carbs.
Lipid processing – produces the phospholipids that make up the cell membrane by adding phosphate groups and glycoproteins to lipids from the endoplasmic reticulum (such as cholesterol).
Golgi bodies in Plant cells:
Although the Golgi apparatus in animal cells is the focus of this article, the Golgi bodies are also present in plant cells. In fact, there could be hundreds of these organelles in plant cells. The primary polysaccharide molecules that contribute to the cell wall formation are synthesized in plant cells by the Golgi complex.
Plants frequently have many more Golgi bodies than an animal cell does for this purpose. Furthermore, lysosomes are absent from plant cells. The central vacuole, which functions as a large lysosome and an organelle to store water, replaces these digestive organelles in the plant. As a result, a huge number of vesicles from plant Golgi bodies transfer to the vacuole and combine their contents with this enormous organelle.
References:
https://teachmephysiology.com/histology/cell-structures/golgi-apparatus/
