Within the eukaryotic cell there are many integral processes that occur in a host of organelles with specialised functions. The focus of each function has allowed eukaryotic organisms to act with great efficiency and yield many products in a single cell. As a result of the complexity of these cells, transport of molecules is an intricate process requiring many compartments to complete the tasks (Cooper 2000). The endomembrane system together with the mitochondria, chloroplasts and cytoskeleton are essential adaptions in ensuring proper functioning of eukaryotic cell processes.
Eukaryotes are larger more complex organisms that can perform more complex and wider range of activities than prokaryotes. The organelles that are only present in a eukaryotic cell allow for the more intricate functions to occur. However along with these processes there also needed to be systems created to allow for activities that need to take place in eukaryotes just like prokaryotes. (Kabnick, Peattie 1991)
Genetic material that allows processes in a cell to occur is present in both prokaryotes and eukaryotes. However, as opposed to prokaryotic cells where the cell information is dispersed throughout the cell, most of the eukaryotes genetic information is housed within a double membrane bound nucleus, separated from the rest of the cell (Davidson 2005). The Deoxyribose nucleic acid (DNA) never leaves the nucleus itself and therefore ensures that no genetic information is lost. Because the genetic information is not freely in the cytoplasm-as in prokaryotes- transcription occurs in the nucleus while translation occurs outside the nuclear membrane along the endomembrane system (Griswold 2008).
Once out of the nuclear envelope mRNA needs to be transcribe...
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...er essential role of the cytoskeleton is to keep all the organelles of the cell in place. In addition to this the cytoskeleton also provided critical tracks that allow the vesicles to transport from the ER to the Golgi body.
The specialisation of organelles within a cell has been advantageous as it allows for complex processes in an organism to occur. Specialised proteins can be produced as the coding is released from the nucleus and is synthesised, modified and transported to the correct location within or outside the cell. Energy is released for its specialised organelle to the rest of the cell to ensure it can function and the cytoskeleton ensures that the cell has the correct structure and ability for motility. With all these adaptation the eukaryotic cell is able to produce more complex processes while still functioning in the correct manner to ensure survival.
There are many different cells that do many different things. But all of these cells fall into two categories: prokaryotic and eukaryotic cells. Eukaryotic cells contain a nucleus and are larger in size than prokaryotic cells. Prokaryotic cells do not contain a nucleus, are smaller and simpler than eukaryotic cells. Two of their similarities are they both have DNA as their genetic material and are covered by a cell membrane. Two main differences between these two cells are age and structure. It is believed that prokaryotic cells were the first forms on earth. They are considered primitive and originated approximately 3.5 billion years ago. Eukaryotic cells have only been around for about a billion years. There is strong evidence that suggests eukaryotic cells may be evolved from groups of prokaryotic cells that became interdependent on each other (Phenotypic analysis. (n.d.).
Eukaryotic Cells are Deemed as a Result of the Evolution of Symbiotic Prokaryotes Both Prokaryotic and Eukaryotic cells over time have sustained very dynamic changes from one another. More specifically we have seen the appearance of a more complicated and organized cell structure, the nucleus. However the big question amongst scientists today is how did these changes first occur? A fundamental concept of this evolution is the belief in the natural progression 'from the simple, to the more complex.' However one popular theory that argues that Prokaryotic symbiosis was responsible for forming the Eukaryotic nucleus is the 'Endosymbiotic Theory' this theory was first proposed by a former Boston University Biologist known as Lynn Margulis in the 1960's.
Mitochondria are sub-cellular organelles which are found suspended in the cytoplasm of majority of eukaryotic cells. One of their functions is to produce energy in a form (ATP) that is useful for all cells to maintain the intra and extra cellular functioning. Mitochondrion has a matrix that is surrounded by two membranes called the inner membrane and the outer membrane. These two membranes are separated by an inter membrane space. The outer membrane has proteins embedded in them (most of which are porins- proteins that allow free transfer of molecules such as nutrients, ions, proteins etc.). While the outer membrane is smooth, the inner membrane is highly convoluted into structures called cristae to increase the surface area of the membrane. [1]
These organelles produce chemical reactions from the energy that the sun gives them. The Golgi complex's structure is made up of many flattened membranes sacs that are surrounded by tubules or vesicles. These are called the cisternae. The golgi complex accepts vesicles from the endoplasmic reticulum and modifies them for usage in the cell.
Mr. Euglena is trapped in a crowded area and must be able to travel to a less crowded area to live. The biological processes of photosynthesis and aerobic respiration allow him to do this. Because of these two processes, energy is given to the kinetosome, which then allows the flagellum of Mr. Euglena to move him to a less crowded area.
The most important and largest cellular organelle is the nucleus, which houses most of the eukaryotic cell’s DNA and is surrounded by a double membrane. The nucleus contains most of the cells genetic material. The nucleus is the control center of the cell.
The start of any evolutionary story told about us lies within the origin of the eukaryote cell. This remarkable event consisted of a revolution of cell type matched in momentousness by the arrival on the biological scene of the prokaryote (O’Malley). Bacteria had a couple billion years head start on eukaryotes and have given rise to many biochemical processes that are essential to the ecosystem (Wernergreen). One organism living within another defines endosymbiosis. Nobody can say the exact origin of the eukaryote cell. The endosymbiosis theory dates back to the earliest 20th century and devotion to different models of its origins is strong and adamant (O’Malley).
Eukaryotic plasma membranes in a fluid state have been found to contain a low cholesterol content of approximately one cholesterol to every 16 lipid molecules (Harby 2001). The effect of additional cholesterol in a plasma membrane on cell membrane fluidity and survival was studied in an experiment by Purdy et al. (2005), who used Chinese hamster ovary cells (CHO) and bull sperm to test this effect. Assuming that changing a membrane's cholesterol content can modify its fluidity at differe...
The nucleus of a cell keeps the cell going as a result of its the mainframe of a cell therefore it controls what happens inside a cell,what the cell will do and the way the cell is going to be used. Found inside of the nucleoplasm, the nucleolus is a consolidated district of chromatin where ribosome manufacturing happens.
The cytoskeleton is a highly dynamic intracellular platform constituted by a three-dimensional network of proteins responsible for key cellular roles as structure and shape, cell growth and development, and offering to the cell with "motility" that being the ability of the entire cell to move and for material to be moved within the cell in a regulated fashion (vesicle trafficking)’, (intechopen 2017). The cytoskeleton is made of microtubules, filaments, and fibres - they give the cytoplasm physical support. Michael Kent, (2000) describes the cytoskeleton as the ‘internal framework’, this is because it shapes the cell and provides support to cellular extensions – such as microvilli. In some cells it is used in intracellular transport. Since the shape of the cell is constantly changing, the microtubules will also change, they will readjust and reassemble to fit the needs of the cell.
Citation: Philips, T. (2008) Regulation of Transcription and gene expression in Eukaryotes. Nature Education 1(1)
The membrane surrounding the nucleus in eukaryotic cells, separate the nucleus from the cytoplasm. Most of the cells we used in the experiments held, were multicellular or consisting of more than one cell. A variety of cells were used in completing the experiments. We used union cells, cheek cells, potato cells, and Elodeo cells. We also used Planaria which is a unicellular organism.
Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. But it also contains highly organized physical structures which are called intracellular organelles. These organelles are important for cellular function. For instance Mitochondria is the one of most important organelle of the cell. Without Mitochondria more than 95% of the cell’s energy, which release from nutrients would cease immediately [Guyton et al. 2007].
Prokaryotic cells do not have a nucleus. The chromosomes which are found in prokaryotes are usually spread in the cytoplasm. In eukaryotic cells the chromosomes remain together inside the nucleus and there is a clear nuclear membrane that is surrounding the nucleus.
Their main purpose is to survive and their functions allow them to do so. All cells have common features whether they are eukaryotic or prokaryotic cells. The common features include a plasma membrane, cytoplasm, ribosomes, and DNA. A plasma membrane which is also known as a cellular membrane, surrounds all cells and its primary function is to protect them. Plasma membrane is made up of two layers of phospholipids which are a class of lipids and has many proteins embedded in it. The proteins have a function of providing support and shape to a cell. There are three different proteins in cell membranes (see appendix 1). The plasma membrane also regulates the entry and exit of the cell, as many molecules cross the cell membrane by osmosis and