This website uses cookies to ensure you have the best experience. Learn more

Explain How Eukaryotic Chromosomes Store A Unique Genotype, Discussing How The Processes Of Independent Assortment, Mutation And Crossing Over Contribute To Genetic Variation Amongst Individuals

2229 words - 9 pages

D1- Explain how eukaryotic chromosomes store a unique genotype, discussing how the processes of independent assortment, mutation and crossing over contribute to genetic variation amongst individuals
Introduction
DNA molecules store the genetic blueprint of an animal, in other words that is called the genotype, or genome. The genome is stored around protective histone proteins (nucleosomes) and packaged into one or more chromosomes. They are coiled and packed very tightly. Inside a DNA molecule there are many different sections that each code for a particular characteristic/trait. This is called a gene. In eukaryotic organisms, DNA is held in the nucleus of the cell, and two copies of each ...view middle of the document...

A DNA strand will split into two single strands, and the junction at where it splits into two is called the replication fork. When DNA has split into two single strands it will join on with free nucleotide bases to create two new strands. The leading strand of DNA is ordered in the 5’ to 3’ direction and is copied almost continuously, but the lagging strand is made in sections, which are called Okazaki fragments
The triplet code refers to the number of bases that code for each amino acid. And, the name tells it, there must be a minimum of three bases in total to make enough combinations. If there are two bases there wouldn’t be enough combinations, so that is why three is just enough. The genetic code refers to the way in which A,C, T and G base sequences in DNA (or U in RNA) instruct for the combination in amino acids.
Gregor Mendel
Gregor Mendel established the basic rules of inheritance of genetically determined characteristics. He stated that genes that are present will always express the trait, these are called the dominant genes. Some genes will only express if there are two copies of the same gene present, these are called recessive. Heterozygotes will process two different versions of the same gene, so this would be a dominant and a recessive gene, and homozygotes will process two similar versions of the same gene, like TT, or tt. This concept can be explained with the Punnett Square, named after R.C Punnett, who created it to represent inheritance patterns
Independent assortment
Independent assortment is the random separation and assortment of non-homologous chromosomes, during meiosis. For a diploid cell with two pairs of homologous chromosomes, independent assortment gives four possible types of gamete. The theoretical number of combinations is 2, to the power of the number of pairs of homologous chromosomes: 2 ²=4 for two pairs, so therefore for the 23 pairs of human chromosomes it would be 2²³= 8388608. This means that independent assortment alone is the source of significant variation. But when this is combined with recombination and the random fusion of gametes, the potential for genetic variation is enormous.

Each member of a homologous pair of chromosomes has exactly the same genes and therefore determines the same characteristics, for example eye colour and blood group. However, the alleles of these genes may differ, for example they may code for brown or blue eyes, or blood group A or B. The random distribution, and consequent independent assortment, of these chromosomes therefore produces new genetic combinations.
Stage 1: one of the pair of chromosomes includes the gene for eye colour and carries one allele for brown eyes and one for blue eyes. The other chromosome carries the gene for blood group and also carries both the allele for blood group A and the allele for blood group B. There will be two possible arrangements, A and B, of the two chromosomes at the start of meiosis. Both are equally likely, but each...

Other Essays Like Explain How Eukaryotic Chromosomes Store a Unique Genotype, Discussing How the Processes of Independent Assortment, Mutation and Crossing over Contribute to Genetic Variation Amongst Individuals

How and to What Extent Did War and Violence Contribute to the Definition of Chivalry as Both an Historical and Social Phenomenon?

1934 words - 8 pages How and to what extent did war and violence contribute to the definition of chivalry as both an historical and social phenomenon? It is largely acknowledged by historians that, while it is difficult to be definitive in the meaning of chivalry-with Maurice Keen believing it to be a ‘word elusive of definition’- it came to denote the culture of a martial estate which ‘regarded war as its hereditary profession’. Thus, it could be considered that

Explain the Relationship Between Discipline and Obedience from the Montessori Perspective. Explain How Discipline and Obedience Are Linked to the Development of the Will

1927 words - 8 pages There are various theories explaining the development of discipline and obedience in early childhood. Montessori perspective establishes a link between these two concepts and how their maturation is dependent on the maturation of the will of the child. This essay will attempt to explain the relationship between discipline and obedience in the developmental stages of a child. Attention will be paid to how the environment helps the child in his

Understand How Individuals and Organizations Make Decisions About the Protection and Usage of Individua

3355 words - 14 pages the protection or revelation of individuals' data does not presume that all privacy trade-os have an explicit monetary dimension. Rather, the economics of privacy tries to understand trade-os associated with the balancing of one's public and private spheres. Even a broader denition of privacy than the one we use in this report (for instance: a person's interest to keep certain activities, interests, or 4 thoughts to herself

Explain What Constitutes the Physical and Psychological Needs of a Three Year Old Child. Explain How These Needs Can Ideally Be Met in a Childcare Setting

2356 words - 10 pages Children have needs that need to be fulfilled to remain healthy. The WHO definition of health is a “state of complete physical, mental and social wellbeing and not merely the absence of disease and infirmity” (MCI undated c pp1). This essay will look at how Early child care settings can fulfil specific physical needs of exercise, rest, nutrition and health and safety of a three year old. It will also look at how settings can fulfil the

Crossing over the Borderline: the Importance of Proper Bipolar Diagnosis

1192 words - 5 pages or need of professional help? My challenge to all of you reading this essay is to reach out to the person who seems most distant, who cries often or who seems way too over the top emotionally and ask them “How are you feeling today?” If we can connect and reach out to at least one person, it could make all the difference between the stability of life or a tragically early death. References: www.nimh.nih.gov -- National Institute of

Assessment In Australia's Schoola: Explain The Processes And Strategies You Would Adopt To Create A Balanced Approach To Assessment In The Primary English Learning Area

1218 words - 5 pages knowledge is known as assessment, and in order to use assessment tools to produce accurate measurements, they must be thoughtfully designed at the outset and integrated into the program, rather than be seen as a separate process (EDWA 1998, 106).This essay will describe the purpose of assessment, and explain the difference between the terms 'assessment' and 'evaluation' and how the two are connected. The main body of the essay will be concerned with

Describe and Explain How and Why the London Docklands Were in Need of Rebranding

739 words - 3 pages Describe and explain how and why the London Docklands were in need of rebranding Rebranding is “a change of image through the development of a marketing strategy.” The London Docklands needed rebranding because it in decline and couldn’t get out of the spiral of decay. This was occurring in the 1970s. A major reason why the Docklands were in decline was because of containerisation. This meant that the London Docks and the River Thames were not

Explain How Tribunals and Arbitration Work and Describe the Types of Cases They Both Deal with?

901 words - 4 pages process and basis for decision are not as rigidly defined as in court. For example, rules of evidence are not as strict, and parties can usually have a say in how they want the hearing to be conducted. Once the decision is made there is very limited right of appeal to this decision. The only right to appeal against an arbitrator’s decision, is through the High Court on a count of “serious irregularity”, such as a violation of natural justice, the

How Do the Physical and Social Settings in the Story "Death by Landscape" by Margaret Atwood Contribute to the Story's Overall Meaning?

754 words - 4 pages . “Every one of them is a picture of Lucy” (Atwood, 36). She is alone, and decades later she continues to be haunted by the loss of Lucy. Both the physical and social settings contribute significantly to Lois trauma: The expansive wilderness, which represented adventure in Lois' youth, comes to represent danger, and a fearful unknown, decades after Lucy disappears. She would not visit places with “wild lakes and wild trees and the calls of loons

"The Brooklyn Reader," explain how they use descriptive techniques to portray Brooklyn. I compared "Southeast of the Island: Travel Notes" and "Sunday Dinner in Brooklyn."

511 words - 3 pages unsuccessful marriages are dealt with: "There is a special bank to which husbands come one day to deposit, estranged wives the next to be fertilized by this genteel equivalent of alimony. It seems significant of Brooklyn that it is probably the only city that has such a bank." Furthermore, Broyard refers to his own family, exemplifying their lack of solidity; over the years it seems as though the special bond they shared deteriorated: "When - and how - had

Evaluate the Contribution Psychological Research Has Made Towards Our Understanding of How Children from Birth to Five Learn and Develop Competencies in the Processes of Observation, Problem Solving,...

3252 words - 14 pages Evaluate the contribution psychological research has made towards our understanding of how children from birth to five learn and develop competencies in the processes of observation, problem solving, exploration, experimentation and prediction, thinking and decision making. Introduction The aim of this essay is to evaluate the developmental theories of ‘Problem Solving, Reasoning and Numeracy’ (PSRN) and an ‘Exploration and Investigation

Related Papers

How Physical And Social Settings Contribute To A Story

646 words - 3 pages How physical and social settings contribute to a story? In the short story “Paul’s Case” written by Willa Cather, there are certain physical and social settings that the story revolves around in order to contribute to its overall meaning. These attributes will help contribute to the characterization of Paul. The protagonist in the story is Paul; who feels lost in his own world that exists in Pittsburg. Paul looks down on most of

Study On The Effects On Attention Via The Interaction Of Automatic And Controlled Processes Using A Variation Of The Stroop Effect

2787 words - 12 pages Study on the effects on attention via the interaction of automatic and controlled processes using a variation of the Stroop effect. ABSTRACT The effect of automatic processing on controlled processing was investigated in this experiment. Previous research conducted by Stroop (1935, as cited in Edgar) had revealed that automatic processing can interfere with controlled processing via response times in naming ink colours of printed words

How Far Did The Rebellions Of 1549 Present A Serious Threat To The Government? Use The Sources And Your Own Knowledge To Explain Your Answer

1128 words - 5 pages How far did the rebellions of 1549 present a serious threat to the government? Use the sources and your own knowledge to explain your answer. The Kett's Rebellion and the Western Rebellion, both of which occurred in 1549 with a variety of other rebellions occurring across the country, both had posed a fairly significant role in threatening on the government. Both of the rebellions however, were located far away from London. The proximity of

How Those Your Chosen Texts (A Selection Of Songs By The Smiths) Contribute To Your Understanding Of “Belonging” With Some Reference To Emily Dickinson

928 words - 4 pages Through exegesis and exploration of my chosen text, “A Selection of Songs by The Smiths”, as well comparisons linked to Emily Dickinson’s set poems, a vast array of representations of belonging have been discerned. Through an abundance of ideas, the texts provide variable discourses as to how we can view belonging, exploring the state of belonging, mainly through its paradoxes. Thus the study of The Smith’s songs individually as well as