How does it work? The mitochondria is the organelle responsible for energy production. These small structures vary widely in shape, from long and slender to short and fat. The membrane is very important in the mitochondria, the outer surrounds the organelle, while the inside membrane contains numerous folds called cristae. This increases the surface area exposed to matrix inside. The reactions from matrix are what provide energy for cellular functions. Why is it important? The mitochondria is important because it is the energy manufacturer of the cell. It is the maker of ATP through the breakdown of sugars that come through the cells.
Endoplasmic Reticulum
How does it work? The endoplasmic reticulum, or ER, is a network of intracellular membranes connected to the nuclear envelope(membrane), that surrounds the nucleus. The ER forms hollow tubes, flattened sheets, and chambers call cisternae. There are two different ERs, the smooth ER, and the rough ER, that have their own functions. The rough ER takes proteins and not only creates them, but also ships then over to the golgi apparatus. The ribosomes that are the rough part of this ER, form as a synthesizer for the new proteins as some of them are eventually used as attachments of carbohydrates, and glycoproteins. The other form, the smooth ER, meaning it does not have ribosomes on it, has to do with synthesis of lipids and carbohydrates. The synthesis that the SER (Smooth ER) performs includes: synthesis of the phospholipids and cholesterol for growth, of steroid hormones, and storage of glycerides in fat cells, and lastly with glycogen in skeletal muscle and liver cells. Why is it important? The ER is important because of some functions, already mentioned, that it performs. The main functions of the ER are what make it clearly important. The ER performs synthesis, storage, transport, and detoxification. All of these are the main reasons, each being used either by the rough or the smooth ER.
Golgi Apparatus
How does it work? Looking like a stack of dinner plates, the golgi apparatus is one of the easiest to identify in the cell. The organelle typically consists of five or six fattened membranous discs called cisternae. A single cell may contain several of these organelles, most often near the nucleus. Some of the proteins that come to the Golgi apparatus are delivered by the rough ER through transport vesicles. These vesicles fuse with the Golgi membrane, and empties its contents into the cisternae. While inside, the enzymes of the Golgi modify the proteins. Why is it important? The Golgi apparatus is important because of how versatile it is. It has three main functions including it modifying and packaging secretion, and renewing or modifying the cell membrane. The versatile function, though, is the third function, with the Golgi being able to have its vesicles carry special enzymes to the outside of the cell, to the membrane, or they create lysosomes.
Lysosomes
How does it work? Lysosomes are one of the complex structures made in the Golgi apparatus, cisternae. They break down and recycle large organic molecules and even complex structures like organelles. Lysosomes are very small, often spherical bodies with contents that look dense and dark. Lysosomes function in the destruction of bacteria that enter the cell and also in cleanup and recycling within the cell. Why is it important? The lysosome is important because of all its functions it does to protect the cell. It breaks down diseases or viruses and destroys them. The lysosome also will clean up the mess it made, and therefore provides protection with the molecules of a virus or disease being taken out by the lysosome.
Peroxisomes
How does it work? Peroxisomes are smaller than lysosomes and carry a different group of enzymes. They are also made in the Golgi apparatus, but are produced by the growth of subdivision of existing peroxisomes. The function of a peroxisome is to absorb and break down fatty acids and other organic compounds. Why is it important? The peroxisome is important because of its function to absorb and break down fatty acids. This function protects the cell from potentially damaging effect of free radicals produced during catabolism.
Nucleus
How does it work? The nucleus is almost always the largest structure in the cell. It is control center for cellular operations. Surrounding the nucleus and separation it from the cytosol is a nuclear envelope, a double membrane with its two layers separated by a narrow perinuclear space. The nucleus receives information about conditions and activities in other parts of the cell in order for the cytosol process to take place. The process then makes nuclear pores. These pores are there as small passages, but not too small that DNA could get through freely. The DNA chromosomes are also held inside the nucleus and the DNA holds the main function of the nucleus. Why is it important? The nucleus is important because of the DNA that it holds. It contains the chromosomes that identify what that cell is made for and what it is to do. This could involve hair, eye, or any physical feature in the body.