Analysis MYB26 gene and male sterile and Anther dehiesence Literature review

Analysis MYB26 gene and male sterile and Anther dehiesence - Literature review Example The Arabidopsis plant produce flowers from April to early June. The plants of this family are known as crucifers due to their uniform flower structure that resembles a ‘cross’ and are also characterized by a fruit named silique which is 5-20mm long with 20-30 seeds. The leaves are alternate (rarely opposite) and sometimes organized in basal rosettes. Figure 1. Arabidopsis thaliana plant: Left, the vegetative stage, before flowering and growth of the floral stalk (bottom left). On the centre an adult plant at full flowering/seed set. On the right, flower, floral stem and seeds. White bars represent 1 cm, except for flower and seeds: 1 mm. (image from http://www-ijpb.versailles.inra.fr/en/arabido/arabido.htm) Taxonomy of A. thaliana Genus Arabidopsis has several species but A. thaliana (L.) Heynh. 2n=10 is the most studied as the model plant. Kingdom: Plantae Order: Brassicales Family: Brassicaceae Genus: Arabidopsis Species: Arabidopsis thaliana (L.) Heynh. Importance of A. thaliana as a model plant Though it has no significant economic value, A. thaliana is widely used as a model plant in studying a wide range of subjects in plant science. This was first proposed as a model plant by Friedrich Laibact in 1943 (Meyerowitz, 2001) and now it is used extensively in studies based on evolution, genetics, population genetics and plant development. It is widely applied in genetic transformation studies, chromosomal analysis, genetic mapping and genome sequencing work. One important trait that makes A. thaliana an ideal model plant in plant science research is its small genome size. It has only five chromosomes with 157 million base pairs (Bennet et al., 2003) and the genetic and physical maps of all five genes are available. This is useful for genetic sequencing and mapping. In fact the first plant genomes sequenced were of A. thaliana in the year 2000 where 115.4 mega bases of the 125mb genome were sequenced (â€Å"Analysis of the genome sequence of the f lowering plant Arabidopsis thaliana†, 2000). Such information provides the basis of understanding molecular biology of many plant traits and research has defined the functions of its 27,000 genes and the 35,000 proteins they encode (Integr8, 2011). In addition, A. thaliana has a short life cycle (six weeks from seed germination to seed maturation), has prolific seed production and the plant can be easily cultivated in restricted space. A. thaliana can be efficiently transformed with Agrobacterium and large number of mutants is available (www.arabidopsis.org). This plant has thus become valuable in genome projects and facilitates molecular level understanding of the biology of a flowering plant. Since Arabidopsis thaliana is similar to many other plants, it is believed that the properties found in Arabidopsis likely to be found in other flowering plants too. Therefore analyzing the structure and functions about Arabidopsis genes will pave the pathway to study about other plant species. Arabidopsis Information Resources (TAIR), located in Carnegie Institute for Science Department of Plant Biology, USA maintain a genetic and molecular biology database of A. thaliana (www.arabidopsis.org). TAIR includes data on complete genome sequence with gene structure, gene product information, metabolism and gene expression, genome maps, genetic and physi

The Relativist Doctrine Essay Example | Topics and Well Written Essays - 1250 words

The Relativist Doctrine - Essay Example Thus, the moral principle in a person, which determines what they perceive as truth, is based on an individual’s circumstances, culture, parental guidance and upbringing as well as ones opinions (Underwood, 2001). Thus according to this doctrine, there is no law that is obligatory to be upheld and to exercise control over all men. The law is based upon what a society or a group of people could perceive as suitable during a particular time and dependent on the situation. As the society keeps changing, so does the circumstances and the situations, necessitating the change of such laws ones upheld as the standard of control of the society. Thus, the standard of morality is also amenable to change, as the society and the environment changes (Sulloway, 1996). However, though this opinion is upheld by the doctrine, there arises a question as to whether there are some categories of behaviors, which can be universally acclaimed right or wrong. Truth is defined as saying of what is, th at it is and what is not, that is not (Sinclair, 1937). Thus, truth refers to the conformity to facts and actualities. Different cultures have different truths, meaning that it is the culture, which determines the truth and not the reverse. Therefore, the variance in different cultures creates the variance in different truth components as perceived by a people (Feynman, 1965). However, there is a different perspective held by the opponents of the doctrine of relativism. They uphold that a truth is acceptable universally, and thus its nature overcomes all the barriers, that of culture included, standing as the absolute right. According to the doctrine of relativism, if a person has a different culture form that of another, then the upbringing, the experiences and the perceptual evidences as held by the individual, determines the different values that the individuals attaches to their beliefs, and thus the difference in truths they uphold (Sulloway, 1996). The philosophy of relativism holds that Man is the measure of all things. Therefore, the truth can only be attained through the determination of an individual, based on how the individual perceives the world (Feynman, 1965). When a person gives an opinion regarding an issue, then it is an indication of their standpoint both psychological and personal. The lack of parallel culture affects the psychological make up in different people, creating an avenue through which culture determines the truth. However, the limitation associated with this perspective is the fact that if truth is relative, then the knowledge obtained by individuals, based on their cultures cannot be universally applicable. This raises a question as to why knowledge principles apply to all regardless of their cultures (Sinclair, 1937). In consideration of the philosophy of relativism, then any truth is determined by the reasoning of an individual, based on his culture. Reasoning allows individuals to create a compromise between different cultur es, assessing their similarity in concurring to beliefs and thus judge on their applicability (Underwood, 2001). Therefore, since not everyone’s truths are true, we generate different knowledge from such truths. Since different cultures imparts different values on an individual belief system, then the justification of issues, through reasoning leads to different knowledge upheld by individuals. Thus, with relativism, in value system and truths upheld by individuals and their cultures, comes about the differences in philosophies,