The Tree of Life
Management Development Institute of Singapore
Bioinformatics Coursework
The Tree of Life
Name: Ren Mengjie
FIN No: G0959068X
Batch No: FUBD0 1321A
Introduction
Since life appeared on the earth, there have been billions of years. Over these years, we have modern world via evolution. Evolution was firstly mentioned in the theory of Natural Selection. There were many evidences for evolution. For example, fossil evidence and natural selection can prove evolution. The fossils proved evolution by recording the process of changes at an order of ages. In addition, evolutionary change can be produced by natural selection. Due to evolution, we have the tree of life.
LGT and Descent
Homology is one aspect of evolution and an important proof of evolution. Homologies are similar structures or genes in different species. For example, a human being’s arm, a dog’s leg and a bird’s wing all have identical bones structure. It supports that they have a common ancestor and separated into different species through evolution. Among homologies, homologous sequences can be created by horizontally acquired variations and vertically generated variations.
Horizontally acquired variation is also known as lateral gene transfer (LGT). It refers to the transfer of genes between unrelated organisms such as bacterial cells without cell division. It plays an important character in the evolution of bacteria. Sometimes, it is used to express allelic interchange among closely related bacterial strains that integration happens by homologous recombination.
In contrast, vertically generated variation (descent) is defined as the transmission of genes from mother cell to daughter cell during cell division. It also occurs when an organism transfers gene material to its offspring during reproduction. It is the way of gene transfer in most of organisms.
The Cambrian Explosion
Although evolution was proved, there was a famous episode of rapid
Bioinformatics Coursework
The Tree of Life
Name: Ren Mengjie
FIN No: G0959068X
Batch No: FUBD0 1321A
Introduction
Since life appeared on the earth, there have been billions of years. Over these years, we have modern world via evolution. Evolution was firstly mentioned in the theory of Natural Selection. There were many evidences for evolution. For example, fossil evidence and natural selection can prove evolution. The fossils proved evolution by recording the process of changes at an order of ages. In addition, evolutionary change can be produced by natural selection. Due to evolution, we have the tree of life.
LGT and Descent
Homology is one aspect of evolution and an important proof of evolution. Homologies are similar structures or genes in different species. For example, a human being’s arm, a dog’s leg and a bird’s wing all have identical bones structure. It supports that they have a common ancestor and separated into different species through evolution. Among homologies, homologous sequences can be created by horizontally acquired variations and vertically generated variations.
Horizontally acquired variation is also known as lateral gene transfer (LGT). It refers to the transfer of genes between unrelated organisms such as bacterial cells without cell division. It plays an important character in the evolution of bacteria. Sometimes, it is used to express allelic interchange among closely related bacterial strains that integration happens by homologous recombination.
In contrast, vertically generated variation (descent) is defined as the transmission of genes from mother cell to daughter cell during cell division. It also occurs when an organism transfers gene material to its offspring during reproduction. It is the way of gene transfer in most of organisms.
The Cambrian Explosion
Although evolution was proved, there was a famous episode of rapid
References: Biotechnology Learning Hub (2008) Factors that influence evolution[online] Available from: http://www.biotechlearn.org.nz/focus_stories/evolved_enzymes/factors_that_influence_evolution [accessed 1st December 2013] BOUNDLESS (N.A.) Evidence of Evolution: Homology[online] Available from: https://www.boundless.com/biology/introduction-to-evolution/evidence-of-evolution/evidence-of-evolution-homology/ [accessed 1st December 2013] Jeffrey G. Lawrence (2005) Horizontal and Vertical Gene Transfer: The Life History of Pathogens[online] Available from: http://www.pitt.edu/~biohome/Dept/pdf/1613.pdf [accessed 1st December 2013] Mr. Osama (2009) The Cambrian Explosion[online] Available from: http://www.sciencesway.com/vb/t4614?langid=2#.Up5or42cG7x [accessed 2nd December 2013] The Burgess Shale (2011) The Tree of Life[online] Available from: http://burgess-shale.rom.on.ca/en/science/origin/01-life-tree.php [accessed 2nd December 2013]