P1 – Describe the microstructure of a typical animal cell and the functions of the main cell components. A typical animal cell is seen as a tiny, three dimensional sac which is in fact made up of many components, each as important as the other. The microstructure of an animal cell was in fact uncovered mainly through the use of both cell fractionation and electron microscopy. Each main component has its own, individual function which helps a cell to function and maintains the cell membrane. The components that I will be describing include the cell membrane, nucleus, cytoplasm, mitochondria, lysosomes, Golgi bodies, centrioles, endoplasmic reticulum (both smooth and rough) and ribosomes.
The cell membrane - The cell membrane is also known as the plasma membrane and is located on the surface of all typical animal cells, it is covered by a double layer of phospholipid known as the bilayer (fat cells) on each individual cell. The lipid bilayer is there to help protect the cell from any uncontrolled flow of water, a barrier that is there to mark the boundaries of the animal cell and is made up of two layers which are known as the exposed hydrophilic (water loving) and the hidden hydrophobic (water fearing). The structure of the phospholipid is made up of the polar heads and the nonpolar tails and is known as impermeable. This means that only water and gases can easily pass through it and that it does not allow other molecules to do so quite as easily, this means that both other small and large molecules need to be assisted by other structures to do so. The heads are composed of phosphorus and the tail is made up of a string of carbons and hydrogen’s. The phospholipids sort themselves into the bilayer which is in fact a natural process so therefore does not require any energy to be carried out so that the hydrophobic tail regions are hidden from water and the hydrophilic regions are exposed to it. The phospholipid bilayer is seen as the basic
References: – * All diagrams, Google, http://www.google.co.uk/. * http://biology.about.com/od/mitosisglossary/g/centrioles.htm, (11/10/12). * http://www.buzzle.com/articles/centriole-function.html, (11/10/12). * http://www.buzzle.com/articles/golgi-body-function.html, (02/10/12). * http://www.cytochemistry.net/cell-biology/ribosome.html, (27/09/12). * Fleur L. Strand, Physiology, USA, Macmillan publishing, (10/09/12). * http://hyperphysics.phy-astr.gsu.edu/hbase/biology/mitochondria.html, (24/09/12). * http://www.sparknotes.com/biology/cellstructure/cellmembranes/section1.html, (18/9/12).