All living things are made up of cells which make up the basic structure of life. Since the cells also reproduce, those that exist in the body at any given time are as a result of the previous cells in the body. In the case of plants, animals and most, if not all living things, the cells are responsible for the development of different parts of the body in the case of animals and parts that make up other living things. Cells in both plants and animals can be divided into eukaryotic and prokaryotic cells. The eukaryotic cells are classified as either plant cells or animal cells and they are distinguished from prokaryotic cells because their cytoplasm contains membranous organelles. They also have chromosomal proteins and a nuclear membrane. Most of the genetic material in a cell is found in the nucleus of the eukaryotic cells and it is responsible for controlling all the activities that occur in the cell as it serves as the cell's analogous blueprint.
The nucleus is also responsible for transcription of cells and replication of DNA. While in the ribosomes, translation of mRNA occurs triggering the protein synthesis for the cells. The ribosomes are important especially because they facilitate protein assembly which also includes enzymes that are responsible for various cellular functions within the cells (Robeneck & Severs, 2007). When it comes to synthesizing lipids and detoxing the body off drugs or other metabolic processes, the responsibility falls to endoplasmic, which is divided into smooth and rough endoplasmic reticulum. The rough endoplasmic reticulum carries out protein synthesis and this is made possible by the ribosomes present. In the case for plants, the cells contain cell membranes and cell walls that regulate the entry and exit of substances in and out of the cell and through this process, the cells are able to maintain its internal balance.
Plant cells tend to differ from those for animals as they possess a Golgi apparatus that moves vesicles from the smooth endoplasmic reticulum to other parts of the cell. The plant cells also have chloroplast which is involved in the photosynthesis process which allows plants to convert light from the sun into energy (Hayat, 2012)The process involves the absorption of carbon dioxide, sunlight and water which is then converted into glucose which is used up by plant cells. Plants also go through cellular respiration like animals and this occurs in the mitochondria where energy is created in the form of ATP and is absorbed by the cells. Photosynthesis can therefore only occur if there is light energy from the sun which is then converted into a chemical energy in the form of glucose.
The survival of cells is greatly dependent on their ability to isolate itself from the environment it exists in and this is made possible by a plasma membrane and also the energy the cell gets through cellular respiration as well as ATP. The cell membrane that isolates the cell from its environment comprises of a phospholipid bilayer that further has proteins attached to it and they serve as the transport mechanism which maintains homeostasis in the cell (Hayat, 2012). The membrane further acts as the receptor sites for the cell and also in the immune system that allows cells performing related functions to recognize each other. Transport in the cell occurs through either passive or active transport. The cells also undergo cellular respiration which is responsible for producing ATP and since it is the cells source of energy, it facilitates the occurrence of various cellular processes among which is the transportation of protein. The process occurs in two main phases, one of which is glycolysis. Glycolysis is the process in which glucose is broken down into pyruvic acid. The pyruvic acid is then oxidized into carbon dioxide and finally to water. The process takes place in the eukaryotes where glycolysis takes place in the cytosol while the rest of the process moves to the mitochondria.
Another important process for cells is cellular reproduction and it is the process in which new cells are formed. The reproduction occurs either through Mitosis or Meiosis. While mitosis occurs for all cells, meiosis only occurs for sex cell or gamete cells. When the cellular reproduction is taking place, the cells make copies of their content and then transfer them to their daughter cells. And it facilitates daily activities as well as promoting growth (Howell, 2000). Other than producing two daughter cells that are identical, mitosis is also responsible for the production of non sex or somatic cells and asexual reproduction. Meiosis on the other hand produces four daughter cells that have different genetic makeup and are responsible for the production of sex cells or germ cells. It is therefore responsible for the genetic diversity achieved through crossing over allowing living things like human beings to reproduce.
Traits from the cells can also be transferred from one generation to the next through Mendelian inheritance. According to Mendels law, the dominant traits are inherited from parents and the process is made possible by chromosomes that transport the genetic material. Since different offspring generations have different genotypes, the cells are able to produce different physical traits or phenotypes as a result of the different gene combinations (Hasan, 2005)The process involves the condensation of DNA into chromosomes and chromatin which in turn allows the DNA to be transferred to the offspring. When mutation occurs however, various complications may come about one of which is cancer. In a case where cell reproduction is uncontrollable, tumors are formed and in the case of cancer, the cells also have mutations which result in uncontrollable division of the cells (Hasan, 2005). The process often occurs at a genetic level and the cancer spreads when it leaves the cell of origin and affects major organs of the body such as the brain. To try and remedy the effects, gene therapy or gene control is carried out where the mutations in the cancer cells are targeted by the gene therapy. If possible, gene therapy would present a faster and more effective way to treat cancer. While there are other methods in use such as chemotherapy, a better solution would give a major boost in the fight against cancer. This is especially because the use of chemotherapy involves a chemical process whose side effects poses great risks to other organs in the body that may not necessarily be affected by the cancer.
References
Hasan, H. (2005). Mendel and the laws of genetics. New York: Rosen Pub. Group.
Hayat, M. A. (2012). Stem cells and cancer stem cells: Volume 5. Dordrecht: Springer.
Howell, S. H. (2000). Molecular genetics of plant development. Cambridge: Cambridge Univ. Press.
Robeneck H and Severs J, (2007) "Cell interactions in atherosclerosis" CRC Press
