Variation and Inheritance
Charles Darwin tried to link his theory of acquired traits and use and disuse in describing how characters get inherited. He said that acquired traits get transmitted from the parents to the offspring. Although they lacked scientific proofs, Darwin’s theories led to the belief that character traits in an individual were mainly acquired from the environment in which an organism lives (Roberts, 61). The theories also led to the belief that the characters that come from the environment can be inherited by the offspring. Recent studies and research have shown that what Darwin called gemmules are cells that contain long thread-like strands called chromosomes (Raven, 2013).
These chromosomes have been found to contain the genetic material or the Deoxyribonucleic acid (DNA). These DNA contains polypeptide chains in which genes are found in pairs called alleles. The genes are the units of inheritance (Lehninger et al., 35). They contain nucleic acids in groups of three that make up what is called a codon. This codon codes for some specific information which dictates cellular activities. They mainly code for some specific proteins which perform various functions in the cell and outside the cell. Therefore, the character traits are also coded for by these genes (Ridley, 71). All the inheritable traits are coded for in the genes. They are transmitted from the parents to the offspring through the process of reproduction. During this process, the DNA makes an exact copy of itself in a process called replication (Griffiths et al., 93).
Since the alleles occur in pairs for every gene, the allele pairs separate, and they move into new different reproductive cells called gametes. Fusion of the male and a female gamete brings together the two halves, and the new individual formed will have alleles from both the male parent and a female parent. The characteristics of this young one, therefore, will be determined by both parents since he/she inherited genes from both of them. Some of the paternal or maternal traits may get expressed at the expense of the other depending on whether the alleles are dormant or recessive (Lewin, 84). From this analysis, we realize that there are scientific proofs that most traits of an individual get inherited.
This article talks about research carried out on identical twins to establish if traits get inherited or they get acquired from the environment. According to the article, the findings of the research proved that the environment may have some influence on the character of an organism. However, it is the genetic makeup of the individual that dictates most of his/her traits. The argument is because the research found out that more than half of the variations in the twins were as a result of heredity. Twins who were raised separately still showed some similar characters, while twins from different parents who were raised together in the same home still did not show similar characters. The differences in eleven traits that were studied on twins who were raised apart were insignificant. Even traits that people mostly assume that are determined by the environment such as leadership and traditionalism. A sense of well-being and zest for life were also found to be hereditary.
The findings of this research confirm what has been proven scientifically, and this confirms that it is the genetic makeup of an individual that determine their traits. The article confirms these facts and even explains why twins look and behave alike even when separated for long. This article, therefore, remains relevant because it clarifies the misconceptions and misunderstandings of people while explaining differences in behaviour of people.
I chose this article because the information in it is very relevant. The article is written in simple language, and the results of the research have been revealed systematically such that it can be read and understood by anybody. It has avoided the technical, scientific terms even though all that is written in it is scientific and finally, the writer’s views are not expressed at all, giving the reader no reason to doubt it. The first sentence tells everything about the article, “The genetic makeup of a child is a stronger influence on personally then child rearing.”
The topic, ‘variation and inheritance,’ is very interesting yet controversial. It explains how children inherit traits from their parents who make them look and behave like their parents. At the same time, it explains why members of the same family are not exactly alike.
When a close family member died in a terrible plane crash, her remains had to be identified through a process called DNA testing. From the knowledge about this test, I realised that DNA of close members of the same family are more or less similar, or they look alike.
The study of variation and inheritance in biology will open ways in which the genes can be studied. The knowledge acquired will help in understanding some common diseases and how they can be managed and treated.
Works cited
Griffiths, Anthony J. F. Introduction to Genetic Analysis. New York: W.H. Freeman and Co, 2005. Print.
Lehninger, Albert L, and David L. Nelson. Lehninger Principles of Biochemistry. Ventura, Calif: Academic Internet Publishers, 2010. Print.
Lewin, Benjamin. Genes Vii. Oxford: Oxford University Press, 2000. Print.
Ridley, Matt. "Genome: The autobiography of a species in 23 chapters (2000)." New York: HarperPerennial.
Roberts, Michael B. V. Biology: A Functional Approach. Walton-on-Thames [u.a.: Nelson, 2002. Print.
