Importance Of Diversity Between Species And Species

Importance Of Diversity Between Species And Species
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Extensive research continuing for many years has concluded that all life on earth shares a common
ancestor, with various evolutionary processes generating diversifications giving us the colossal
variety of organisms that occupy the earth today.This essay will explore the source and importance
of diversity with and between species using examples from the order Squamata, class Reptilia,
comprising of over 9000 different species (Uetz, 2014) of lizards and snakes, (HABITATS)
Diversity within and between species is created by genetic variation; a process that allows new traits
to originate which will then become more or less prominent in a population through Natural
Selection.The factors mainly responsible for this diversity ... Show more content on Helpwriting.net
...
Each of these typically dark skinned lizards have evolved white skins (Figure 1) through mutation
of the MC1r gene, encoding for the Melanocortin 1 receptor protein that generates the production of
the dark pigment melanin. In each species, a different amino acid in the MC1r has been swapped
(Figure 2) resulting in the absence of the dark pigment hence the lizards bleached skin (Rosenblum,
2009). This acts as a mode of camouflage and aids lizard in avoiding predation.
Sexual Reproduction
The chromosomal activity following sexual reproduction plays a vital role in generating genetic
variation through the production of unique chromosome combinations. Independent assortment
occurs during meiosis when both maternal and paternal homologous pairs separate independently,
distributing chromatids from each parent to the gametes independent of each other (Mendel, 1865).
As maternal and paternal chromosomes carry different genetic information, independent assortment
produces different possible combinations of chromosome pairs. Recombination is a feature of
independent assortment, producing further new gene combinations by breaking and recombining
DNA fragments. Following this is crossing over; the exchange of genetic material during meiosis
between non sister
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Differences Between Meiosis And Eukaryotes
Eukaryotes can reproduce in two ways, via mitosis and meiosis. Mitosis is a process of cell division
where a single round of replication is followed by separation of sister chromatids to form 2 daughter
cells that are genetically identical to the parent cell. On the other hand, during meiosis, a single
round of DNA replication is precedes two rounds of cell divisions leading to the formation of
haploid gamete from a diploid parent (Figure 1). Figure 1: In meiosis, the DNA replication occurs in
S phase followed by two rounds of replication. Homologs are segregated during meiosis I and
sisters during meiosis II.
Meiosis I is a reductional cell division, where sister chromatids are mono–oriented and homologous
chromosomes that are pulled to the opposite poles. The proper segregation of homologous
chromosome is mainly ensured by meiotic recombination that leads to the formation of a physical
link between them (Chiasmata). Meiotic recombination also leads to the exchange of genetic
material between the homologous chromosomes, leading to genetic variation. Meiosis II (like
mitosis) is an equational division, where the sister chromatids are segregated to form gametes with
half the genetic composition as the parents. The two gametes from different individuals so formed
then fuse via ... Show more content on Helpwriting.net ...
Three of these are subsequently degraded and one undergoes a round of mitosis. The conjugating
partners exchange one of the progeny MIC that fuses with the other to form a diploid MIC. The
zygotic MIC undergoes two more rounds of mitosis. 2 of these form the new MIC and 2 form a new
MAC and the parental MAC starts to degrade. For the formation of the new MACs from the zygotic
MAC, RNAi mediated DNA elimination and chromosome breakage sequence followed by telomere
addition leads to the formation of the mini–chromosomes with a reduced genome size (from 120Mb
to

What Are Genes And Genes?
1. What are Traits? All human beings are unique from one and another, each complex organism has
certain traits that can be seen some harder than others. Some traits that are easier to see such as hair
and eye color, the other ones that are harder to see are vocal talents, Asthma, and disease risk. Traits
can be created through the environment or through genes. The environment can change traits such
as the things we enjoy or the sounds that we create, like language, the language we speak is
considered environment change. Though eye color or body shape is inherited through our parents
giving us some identical genes. Although with twins they are a bit more genetically close, yet they
are not 100% DNA matches, all human beings will have a small amount of traits that are different,
but those who are fraternal twins do share closer DNA than those who are born years a part.
2. What are DNA and Genes? The instructions to create any living organism complex or not is found
from within DNA, also DNA in all organisms looks exactly the same. DNA has four tiny building
blocks that are like the back bone, these building blocks have a chemical letter. These chemical
letters A, C, T, and G, these chemicals create the only two strands in DNA and they only go with
one another one being A to T and C to G, these work in genes, each gene is told to build a certain
protein and a complete set of genes is called a genome. A genome is a set of instructions to build an
entire organism, humans have

Genetic Variation Research Paper
Genetic variation is important in many ways, it is the whole reason why people look and act
different from eachother and why we have advantages over some things. Without variation, we
would all be the same organism and we would all have the same advantages, but we would also
have the same weaknesses and we would never be able to survive long enough and we would all go
extinct. Genetic variation is mainly caused by two sources, mutations and recombination.
A mutation is a change in an organism's genetic information, also known as DNA. Mutations are
random and can happen anywhere at any time. There are two types of mutations, point mutations
and frameshift mutations. A point mutation is a change in a single nucleotide of the DNA and there
can ... Show more content on Helpwriting.net ...
Sexual reproduction is just random changes that are caused by meiosis, or crossing over.
Recombination happens when two of the same species of organisms pair up and when they are
having a baby random fertilizatio happens and that is when a random sperm and egg combine and
once the sperm and eggs combine to create a gamete(a fertilized egg). When the sperm and egg
combine their traits that are in the DNA of the egg and sperm start creating the pheneotypes of the
fertilized egg. Soon the egg goes through meiosis and mitosis and create a completely different
organism from the mother and father, this is also known as variaton.
There are many advantages to variation such as new genes that can benefit us, such as lactose
digestion or stronger bones. There can also be risks to cariation such as cancer, and genetic diseases.
Other times, genetic variation can have no benefit at all or be nuetral, such as different forms in the
gene, eye color and hair color, or silent mutations. Even though genetic variation doesn't sound that
important it really is because without variation we wouldn't have the diversity of life we have

O, N, And B. D. H. J. T 's Mutation
One day after setting up the replica plates, we observed thick growth in all the intersections of Min
+ His and thick growth everywhere the strains were placed (see figure above), which suggests that
the matings and the cellular transfer were successful, respectively. We observed thick growth on the
min plate at intersection of P and his1, P and his4, and P and his5 while observing no growth on his3
and P, which suggest P's mutation is within the same gene as his2. For the sake of space, see table
Min Plate Intersectional Growth for O, N, and Y stains complementation test. Therefore, we
conclude that P's mutation is in the same gene as his3, O's mutation is in the same gene as his1, N's
mutation is in the same gene as his5, and Y's mutation is in the same gene as his4. Thus, the
genotype P is his1+, his3, his4+, his5+, leu 2+, ura3+, and trp1+. O is his1, his3+, his4+, his5+, leu
2+, ura3+, and trp1+. N is his1+, his3+, his4+, his5, leu 2+, ura3+, and trp1+. Y is his1+, his3+,
his4, his5+, leu 2+, ura3+, and trp1+.
The second day after setting up the cross, we observed growth in the way of 3 colonies that grew on
the min on stains his1, his4 and P; and 7 colonies that grew on min + his plate on stains his1(3 and
one of which was at the same spot as on the min plate), his4 (3 colonies), and his5 (1 colony). On
the third day, we observed no new colonies. The colonies described above that we saw form on day
2 outside of the intersections after setting up the replica plates were

Examination Of Cell Division And Dna Replication
The experiments of the past week allowed examination of cell division and DNA replication, the
processes by which cells carry out important functions. It is important to have an understanding of
these processes in order to have an understanding of biology. These most small occurrences are the
basis for life in all cells. Without division and DNA replication, organism could not grow and carry
out complex tasks, such as metabolism. In addition, natural selection can only occur where genetic
variation does. This makes division of cells and the recombination of their DNA essential to the
continuance of human life.
Cells that are diploid have two sets of chromosomes, one coming from each parent. This kind of cell
is most familiar to us because this is the way humans are genetically formed. However, the process
of replicating and packaging those genes is more complex than most people realize. The process
begins in the nucleus. The nucleus is the epicenter of control for the cell. In every nucleus there is a
set of chromosomes with our genetic makeup attached to them. These chromosomes are essential to
the life of the cell. Therefore, when cell division, or mitosis, or occurs, each cell gets a copy of the
entire set of chromosomes, rather than just a part of them. Each phase of mitosis carries out a very
specific task.
Interphase is the beginning of this process. In this stage, you cannot yet discern chromosomes in the
nucleus. The nucleolus, however, will be visible at this time.

Why Genomic Rearrangements Are Important for Lymphocyte...
Why genomic rearrangements are important for lymphocyte function.
Introduction
Through a series of steps called the immune response, the body's immune system attacks invading
disease–causing organisms and substances. The cells involved in this immune response are called
leukocytes. Leukocytes are produced and stored in the thymus, spleen, and bone marrow (lymphoid
organs). There is also lymphoid tissue throughout the body that houses leukocytes (lymph nodes).
The leukocytes circulate through the body between the organs and nodes via lymphatic vessels and
blood vessels.
Lymphocytes are a type of leukocyte. The two kinds of lymphocytes are B lymphocytes and T
lymphocytes. Lymphocytes either mature in the bone marrow and become B cells, ... Show more
content on Helpwriting.net ...
The main problem with chromosome instability produced by these breaks is the susceptibility to
translocations and thus oncogene activation.
Translocations can cause strong transcriptional factors to be moved close to a target oncogene which
will increase its expression. Or, they can result in the creation of a fusion gene that encodes a novel
oncogenic protein.
Oncogenes can also be activated by the amplication of proto–oncogenes. Gene amplification is an
increase in the cellular copy number of a gene or genomic region relative to the rest of the genome.
An amplication in a proto–oncogene would cause an increase in cell division, a decrease in cell
differentiation and an inhibition of cell death – the phenotype of a cancer cell.
In addition to translocations and gene amplifications, deletions can occur and also result in
oncogene activation. This can be by the removal of negative regulatory elements or the elimination
of regulatory protein domains. However it is more common for a deletion to cause the loss of a
tumor suppressor and therefore lead to a cancerous cell i.e. one which rapidly divides.
Conclusion
Lymphocytes are vital to the human body to protect us against disease and initiate an immune
response. Each person possesses billions of lymphocytes which collectively provide an individual
with the ability to respond to a huge variety of antigens. The wide

Interview Sixth Grade Life Science Students On The Topic...
I chose to interview seventh grade life science students on the topic of cell division. Because I teach
at a magnet junior high/ high school within Toledo Public students, the students I teach in the
seventh grade are coming from a variety of different elementary schools both in and out of the
district. This results in a wide variety of prior content knowledge in science. Based on the Ohio New
Learning Standards for Science, in the sixth grade, students are introduced to the idea of mitosis and
that cells come from pre–existing cells. However, based on my past two years of experience
teaching seventh grade life science, this is often not the case. Most students have a basic
understanding of cells, but have not been introduced to mitosis, nor the major component of cell
theory that all cells come from pre–existing cells. It may also be important to note that my seventh
grade class incorporates both seventh and eighth grade life science standards from the Ohio New
Learning Standards for Science.
Interviews began as students were shown a model of a cell which is shown in Image 1. Students
were first asked the stem question, "What is this a model of?" From there students were asked,
"Where do cells come from?" The probing questions asked to students were dependent on their
responses, but were asked in order to reveal their knowledge of cell division. Three student
responses are described in this paper, as they revealed a variety of prior content knowledge. Three

Drosophila Melanogaster Linkage And Inheritance Essay
Drosophila melanogaster, Linkage & Inheritance
Peggy Chang 999349986
BIOC15 Peter, PRA002
University of Toronto Scarborough
Abstract
This experiment studied Mendel's law of independent assortment through observing three
generations of Drosophila melanogaster. His law was examined by looking at the inheritance
patterns that predicted genetic linkage, mapping distances and interference. Genes are located along
chromosomes and the distances between them vary. During recombination, these genes may become
unlinked. The frequency to which this occurs relies on the recombination frequency, in which a
greater value represents a greater distance between two loci. By looking at inheritance patterns and
recombination frequencies, this experiment showed that white eyes, short wings and forked bristles
are X–linked traits. As well, dumpy wings and brown eyes are autosomal traits. The expected ratio
of a dihybrid cross of 9:3:3:1, was used to determine linkage between two loci. This was then
verified using a chi–square test. Through analysis of our results, linkage existed between white eyes
and short wings, as well as between short wings and forked bristles. Linkage was also found for the
strains that had dumpy wings and brown eyes.
Introduction
Gregor Mendel, known as the father of genetics, paved the way ... Show more content on
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These strains were moved to stock vials and labelled A, B, C, D respectively. Each strain was
observed using a dissecting microscope that allowed for the mutations to be visible. Strain A was
observed to be wild type in all its traits. Strain B however was found to have white eyes, short wings
and forked bristles. Strain C was observed to have dumpy wings and lastly strain D had brown eyes.
Strains and their corresponding mutations can be seen in Table 1. The genotypic notation given to
wild type traits and mutant traits can be seen in Table

Biology Lab Report Essay
Through this lab, what we are trying to figure out is the evolution of sexual reproductions. Even
though, it is commonly known that the cross–over happens during meiosis, which causes the genetic
variations through the exchange of DNA sequences, we do not know much about the factors that
vary these reproductions. In "Evolution Canyon", the organism called "Sordaria fimicola" has been
studied by scientists due to their difference in cross–over frequencies. There are two types of slope
in "Evolution Canyon.": the South Facing Slope(SFS) which receives higher solar radiation, causing
high temperature and draught, and the North Facing Slope(NFS) where the temperature is cool, and
humid. Scientists found out that strain from SFS have higher mutation rates than that of NFS.
However, we do not know yet if the environmental pressures caused the difference in these cross–
over frequencies and we are trying to figure it out through this lab. ... Show more content on
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First, 4:4 can occur when recombination doesn't happen. Secondly, 2:2:2:2 can happen when all of
the pairs of chromosomes are ordered in line and then recombine. Lastly, 2:4:2 recombination
occurs due to independent assortment. So both 2:2:2:2 type and 2:4:2 types occur through
recombination. The effects of radiation on DNA are cell killing and mutagenesis. Continued
exposure to radiation can cause bad effects on living matter. "Radiation either ionizes or excites
atoms or molecules in living cells, leading to the dissociation of molecules within an organism. The
most destructive effect radiation has on living matter is ionizing radiation on DNA. Damage to DNA
can cause cellular death, mutagenesis (the process by which genetic information is modified by
radiation or chemicals), and genetic transformation. " (Joseph Chao, Linda Su(date not found).The
Effects of Radiation on Matter. Retrieved

Why Do Offspring Differ from Their Parents?
Why offspring produced by the same parents are different in appearance
Offspring differ somewhat from their parents and from one another. Instructions for development
are passed from parents to offspring in thousands of discrete genes, each of which is now known to
be a segment of a molecule of DNA. This essay will explore some of the reasons behind how and
why these differences in appearance arise, from the base sequence of DNA through to the observed
phenotype.
Genes come in different varieties, called alleles. Somatic cells contain two alleles for every gene,
with one allele provided by each parent of an organism. Genotype refers to the information
contained in an organisms DNA, or genetic material. Its phenotype is the physical ... Show more
The problem with crossing over is that some unexpected results can occur. For instance, the
offspring of a bull homozygous for two recessive but desirable traits and a cow with "normal" genes
will all have one copy of each recessive gene. But when these offspring produce gametes, one
recessive gene may migrate to a different chromosome, so that the two traits no longer appear in one
gamete. Since most genes work in complicity with others to produce a certain trait, this can make
the process of animal breeding very slow, and it requires many generations before the desired traits
are obtained
In meiosis the pairs of chromosomes (that code for possible outcomes of characteristics) temporarily
join and exchange information (crossing over) creating different combinations of gene types
(alleles). For example; a pair of chromosomes could be a dominant allele (gene type) and a
recessive allele which might code for brown hair. After crossing over it might be recessive which
could be blond hair.
Chromosomes line up in different orders (random assortment) so when they go to either new cell on
cell might have dominant for one characteristic (e.g. brown eyes), recessive for another (e.g. blond
hair), and dominant for a third one (e.g. can roll tongue) whereas the other created cell might be
dominant, dominant dominant (brown eyes, brown hair and can roll tongue.
More rare is mutation where DNA is randomly altered (although certain things can make this more
likely e.g. UV light).This

Cre Recombinase Activity Essay
The major conclusion of this study is that our novel split–Cre complementation system introduces
both temporal and special control of site specific recombination using Cre recombinase enzyme.
This system solved many drawbacks have emerged during the extensive use of Cre recombinase in
molecular biology. The complemented protein is almost as efficient as the Full CRE in the
recombination activity (~95%). Moreover, each fragment lacks the recombinase activity. This
system allows precise genetic manipulation. It has a special importance in neuroscience lacking
selective promoter region for conditional knocking our specific gene at specific brain tissue. Many
websites, such as GenePaint; a digital atlas for gene expression pattern in mouse ... Show more
They depended on the linker used by Jullien et al (19). We depended on the designing criteria of the
linker for efficiently separating domains in bifunctional proteins (40). They reported to use
rapamycin–dependent dimerization or ɑ–helix interactions for enhancing posttranslational
association between the two fragments. Some trials used artificially designed antiparallel Leucine
Zipper to assist protein fragment reconstitution (41). In our study, we used yeast GCN4 coil/coil
Leucine Zipper domain which previously used by some split–Cre systems (19). This Leucine Zipper
does not interfere with normal cellular physiology (30). Each protein fragment behaves as an
independent protein. It has different kinetics than the other protein fragment. We tested the
recombinase activity on synthetic construct and on mammalian genome. We have optimized the
system to choose the best spatial and temporal control of the Cre recombinase. Meanwhile, the
reconstituted CRE recombination was not present in all cells. We had to sort cells expressed both
nCre and cCre fragments. There are two possibilities for this finding. First, the reconstituted CRE is
too low to induce complementation. Second, there is difference in the expression pattern between
the two promoters in each cell due to epigenetic factors.
Tyrosine family site–specific recombinases and type IB topoisomerases are characterized by a

How Double-Strand Breaks
One explanation as to how x–rays effect cells is that the radiation causes double–strand breaks
(DSBs). A double strand break is a lesion within DNA which can prevent replication, cause
deletions, or cause translocations of the DNA. All of the named effects have the potential to cause a
mutation to a cell (Negritto, 2010). Double–strand breaks are known as genomic rearrangements
because it has been shown to change the genetic code of a cell. All of the effects of DSBs may lead
to an increase in the recombination of genes in chromosomes, which may explain how the cells are
mutated. In one experiment, cells were exposed to x–ray radiation in order to test the frequency of
DSB. H2AX is a type of proteins that repairs double–strand breaks

Natural Selection In Animals
If natural selection is to result in the evolution of traits associated with adaptation within a given
plant population certain conditions such as sexual reproduction, mutations, and gene flow, all of
which facilitate genetic variation, must exist. While plants can reproduce asexually, those that
reproduce sexually produce new alleles through genetic recombination. This allows for the
emergence of new phenotypes, and subsequently new individuals, that are better suited for their
environment. Likewise, mutations, which are changes in DNA, can add genetic variation to a
population and create phenotypic changes. If these alterations result in individuals being better
suited to their environment, natural selection will select for these traits,

Advancements in the Field of Genomics
The field of genomics is quickly and steadily gaining momentum in the field of systematics. Based
on an organism's genetics, it applies novel methods of DNA sequencing and bioinformatics to
sequence, construct, and analyze the structure, and consequently, the function, of entire genomes,
using the resulting genetic information from different specimens in fine–scale genetic mapping.
Advancements in other fields such as human biomedicine may also be dependent on progress made
in genomics, especially unresolved problems focused on changes in genes triggered or disrupted in
development, susceptibility to infectious disease, mechanisms of DNA recombination and genome
plasticity which cannot be adequately interpreted without a precise evolutionary context or
hierarchy.
One of the most well–known and supported endeavors in the advancing field of genomics is the
human genome project whose creation has since revolutionized the related fields of proteomics and
medicine with comparative genomic analyses of primate species offering considerable potential in
defining the processes responsible for molding and transforming the human genome. In spite of
these scientific advancements, however, very little information is known about genomes in some
species like the primates. Primate taxonomy is both complex and controversial with close to nothing
in terms of unifying consensus of the evolutionary hierarchy of extant primate species. This lack of
knowledge of the specific hierarchies in

Does Linkage Disequilibrium Cause Genes
In this article, the researchers sought to determine if linkage disequilibrium could be used to map
disease–causing genes. This is of practical importance to the human population in that, it could lead
to earlier diagnosis and prevention or delay of disease progression. The researchers evaluated work
of previous studies and expanded it to a larger section genome samples. This allowed the
researchers to obtain a greater depth of knowledge in comparison of multiple regional ethnicities.
Linkage disequilibrium is the non–random association of alleles at different loci. Disequilibrium
occurs when the frequency of a certain allele is either higher or lower than the expected value given
by independent assortment and random association. Linkage disequilibrium ... Show more content
on Helpwriting.net ...
This, they explained, was probably due to an event that occurred after humans left Africa and
migrated to Northern Europe. They compared the gene samples to those of populations from Nigeria
and found that there were similarities farther away from the core SNP that they were examining.
This showed that there was a common ancestor between all groups and further proved their theory
that an event after migration was the cause of the differences and similarities between the Nigerians,
Utah, and Northern Europe

Sordaria Finicola Lab Report
Genetic Variation in Sordaria Finicola
Introduction:
The purpose of the Sordaria Lab was to explore the affects of genetic variation caused by meiosis
and to record how sexual reproduction] affects the amount of crossing over in certain strains of
Sordaria Fimicola. These organisms are ascomycetes and are also known as sac fungi. This is
because the shape of their asci is in the form of a sac; inside each sac there are structures called
ascospores. It is these structures, ascospores, where genetic variation that arises from crossing over
is easily seen (Davidson). The organism Sordaria Fimicola is a good example of this process
because it is easy to grow on agar plates and because they are easy to be seen when looked at
through a ... Show more content on Helpwriting.net ...
Record the two strains that the group is given in your notebook.
* * * * * * * * * * *
After the agar plate is set up it should look like Figure 3 below. This is an example of the Tan and
Wild Type set up. The Gray and Wild type set up will look the same. Figure 3 (Sordaria Genetics...).
After two weeks of incubating, we followed the steps below to examine the Perithecium Squashes
(Sordaria Genetics...).
The prepared squashes looked like the figure below when looked at under the microscope.
Figure 4 (Sordaria Genetics...):
Each group member is expected to locate and count twenty asci and record their data in the tables.
All the data will be gathered together from all the students in the course. This data will then be used
to calculate the cross over frequencies between the two types. This can be calculated by using the
formula Type B or C/Total number of asci. Then the frequency of recombination will be calculated
from the data using the formula ((Type B+ Type C)/total number of asci). And finally the map
distance will be calculated for both the tan spore and the gray spore by using the formula (Percent
Cross over/2).
Results:
Table 1: Combined Course Data (Tan Spore Color)

Number of Type AAsci (4:4) | Number of Type B Asci (2:4:2) | Number of Type C Asci (2:2:2:2) |
Total Number of Asci | 5669 | 4301 | 3976 | 13946 |
Table

Essay On Mutation
Spontaneous mutations occur during a normal cell process creating genetic changes (text p.206).
There are varying types of spontaneous mutations including, silent, missense, nonsense, and
frameshift mutations. How are these mutations the same and how are they different? Silent,
missense, and nonsense mutations all occur when base substitutions happen (text p.206). A base
substitution is when the wrong nucleotide is incorporated during DNA synthesis, this is the most
common mutation (lecture). In a silent mutation a base substitution occurs, incorporating an
incorrect nucleotide, the result is a codon that codes for an amino acid that is the same as the wild
type (text p. 206). In a missense mutation, the resulting mutant codon does not ... Show more
These mutations are ones that often produce stop codons, putting a halt to the creation of the protein
with shortened amino acid sequences. They may also generate proteins that do not function. By
simply adding a single nucleotide you alter the coding outcomes of the remaining nucleotides down
the sequence. If one were to insert a sequence of three nucleotides, they would be inserting a
complete amino acid. Because of this, there is a higher likelihood that the sequence of three
nucleotides would simple produce a new amino acid, rather than a stop codon, unless it itself was a
stop codon. This creation of a new amino acid to the sequence would elongating the genetic
sequence and continue to produce a functioning protein while allowing the remaining gene sequence
to remain the same. Example 1.1: Insertion into a reading frame:
Reading Frame 1: Wild Type
AUG–––UUA–––UCA–––UAU–––AUC–––UAG
Met Leu Ser Tyr Ile STOP
The above frame demonstrates gene sequence with start and stop codons.
Reading Frame 2: Single Insertion:
AUG–––UUA–––UCA–––UAA–––UAU–––CUA–––G
Met Leu Ser STOP Tyr Leu The above frame demonstrates gene sequence with the insertion of a
single nucleotide, resulting in a stop codon.
Reading Frame 3: 3 Nucleotide Insertion:

AUG–––UUA–––UCA–––CCU–––UAU–––AUC–––UAG
Met Leu Ser Pro Tyr Ile Stop
The above frame

Dr Lab Report
Introduction
Maintenance of genomic integrity is crucial for cell survival in resistance to endogenous and
exogenous environmental insults to the genetic material. Multiple DNA repair pathways coordinate
the response to such genotoxins and protect our genome [1]. Endogenous insults may be generated
as a byproduct of cellular metabolism in the form of reactive oxygen species or during physiological
processes such as meiotic recombination, mating–type switching in yeasts, V(D)J recombination
and DNA replication–transcription collision [2–5]. Exogenous stresses include hypoxia, radiation
and dietary carcinogens [6, 7]. Depending on the nature of damage to the DNA structure which, may
range from breaks in phosphodiester bonds such ... Show more content on Helpwriting.net ...
NER is a highly conserved DNA repair pathway that is the primary pathway responsible for the
removal of bulky DNA lesions i.e., helix–distorting lesions such as UV– induced photoproducts,
environmental mutagens, and some chemotherapeutic agents. NER has two distinct subtypes: global
genome repair (GG–NER), which can occur anywhere in the genome and transcription–coupled
repair (TC–NER), which removes distorting lesions that obstruct transcription [20, 21]. Following
lesion recognition, the damage–containing oligonucleotide is excised from DNA by a dual enzyme
incision step mediated by ERCC1–XPF, which makes the first incision and XPG which incises the
3' end of single/double strand junction [22]. This results in the release of lesion–containing
oligonucleotide with TFIIH bound to it [23]. The gap–filling step in NER relies on the concerted
action of DNA ligase and its cofactors DNA polymerases δ and ε, the sliding clamp PCNA, the
clamp loader RFC and RPA [24]. MMR is a is a highly conserved post–replication repair pathway
that corrects DNA mismatches generated during DNA replication that escapes the proofreading
function of DNA polymerases thereby preventing mutations and tumorigenesis [25–27]. MutSα
recognizes the mismatches and MutLα forms nicks at the 3′– or 5′–end of the mismatched base that
are substrates for the EXOI exonuclease that excises resulting DNA segment is excised by the
EXO1 exonuclease in association with the single–stranded

Genome Editing Essay
Genome editing of germ line cells using CRISPR/Cas9 system
Recent studies suggest that genome editing of germ line cells is an effective strategy for mutated
gene correction in sperms and oocytes for the inhibition of onset of inherited disorder. The first
time, germ line genome editing in human by CRISPR/Cas9 system , was carried out to correct
mutation of HBB (Beta globin) gene in zygote of β–thalassemia patients by homologous DNA
recombination (HDR) [80, 81]. Embryonic genome editing utilized in the treatment of such
monogenic diseases prior to birth is a rational use of embryonic genome editing in germ line cells.
Homologous DNA recombination by traditional gene editing techniques in mammalian eggs has a
low rate (<10%) in term of ... Show more content on Helpwriting.net ...
Because PGD usually is carried out by gametes prepared from parents. But parents who is
confirmed by PGD to have a high risk of transmition of inherited genetic mutation to their children
and want to have their own children, their gametes can be edited directly by Crisper/cas9 to create
healthy children.Nowdays germ line genome editing by programmable nuclease such as
Crisper/cas9 is the most useful tool to treat genetic diseases with high risk of inheritance mutation
transmition.
Unresolved ethical problems still exist and are the main reason for delay onset of clinical trials in
this field. Large animal models can be utilized for a variety of monogenic diseases, particularly
monogenic neurological disorders like HD and Duchene muscular dystrophy) DMD (. Specificity,
efficacy, and side effects of germ line genome editing technology should be assessed by animal
models before entering clinical trials.
Generating mammalian models of neurodegenerative diseases using CRISPR/Cas9
Cas9 has been well studied. It belongs to the class II CRISPR/Cas system which is the main protein
involved in small interfering CRISPR RNA (crRNA). CRISPR RNA often leads to the silencing of
invader viruses and plasmids [72, 85]. Several in vitro surveys have shown that Cas9 is guided by
gRNA composed of chimeric RNA. Chimeric RNA is composed of crRNA and tracrRNA. They are
sufficient to

Inherited Genetic Variations
Inherited genetic variations may result from new genetic combinations through meiosis,
nondisjunction errors occurring during cell division and through mutations in the DNA of egg and
sperm cells.
Meiosis is a cell division that results in four daughter cells. The daughter cells have half the number
of chromosomes of the parent cells.In meiosis the Law of Independent Assortment states that the
alleles of one gene sort in gametes independently of the alleles of another gene. Meiosis increases
inherited genetic variation because during meiosis, homologous chromosomes each from one pair of
parents. The parents chromosomes cross over and and trade some genes when they break apart. This
recombination of forming together then breaking apart and

Genetic Drifts: What Is Proteomics?
Question #5 (1 Point)
What is proteomics? With modern advances to genome sequencing, whole genomes can now be
used to rapidly identify protein encoding sequences from a small amount of amino acid sequences.
This has led to a field of study called proteomics, which encompasses the study of proteins, protein
complexes, and protein–protein interactions. As an example when one isolated protein is found to
interact with a complex of proteins known to be part of an enzyme complex, it could be inferred that
the isolated protein may be part of the enzyme complex as well. Some of the techniques involved
for studying proteomics are interaction assays that allow for the rapid identification and purification
of proteins. A genome wide protein–protein ... Show more content on Helpwriting.net ...
This would occur by the genomic restructuring mechanism recombination has, particularly in areas
with repeated sequences. Recombination of transposable elements, which many contain repeated
sequences, as well as other repeat sequences found in the genome, may be one of the main
mechanisms by which genetic regions are rearranged, lost, or duplicated. Recombination can result
in the following: translocations, in which repeated sequences on two different chromosomes are
swapped with a region of another chromosome, possibly lead to a change in the copy number of
genes; deletions, in which a loss of a region of a genome occurs, usually decreasing fitness and are
selected against over time; duplications, which result in the presence of extra copies of specific
regions of the genome; inversions, which lead to a change in the order in which they are found,
resulting in alterations in gene expression without changing the copy number of

Recombination Frequency In Sordaria
This study examined the effects of X–ray radiation on recombination frequency in Sordaria
fimicola, a model organism. A Laboratory Manual for Biology 110 Biology: Basic Concepts and
Biodiversity states that S. fimicola:
...offers many advantages, including a substantial body of research into aspects of its life cycle and
genetics, a rapid life cycle allowing studies to be conducted in a timely manner, ease of isolating
strains from the wild and grown them in the laboratory, and the fact that it produces fruiting bodies
(perithecia) containing narrow, elongate asci with eight spores that are easily viewable under the
microscope, and whose order reflects events that occur during meiosis (Burpee, Cyr, Hass, Ikis,
Richter, Ward, & Woodward, 2015). ... Show more content on Helpwriting.net ...
Treatment one consisted of Wild Type and Tan S. fimicola isolates that were both treated with X–ray
radiation. The second treatment was Wild Type treated with X–ray radiation and Tan without
radiation. Finally, the third treatment consisted of Tan isolates treated with X–ray radiation and Wild
Type isolates without. A control plate was also tested to use as a comparison (Burpee et al., 2015).
For control plates and all three of the treatments, petri dishes were prepared to cross the isolates,
producing perithecia. First, two 0.5 cm squares of fungal hyphae containing agar were cut from a
cultured petri dish. Wild Type and Tan isolates were used for the control; X–ray samples
corresponding to the correct treatment were used for the experimental plates. The agar squares were
then placed with the hyphae side facing the agar on the quadrant labeled for the corresponding
isolate. These steps were then repeated for the remaining strains/ culture plates (Burpee et al., 2015).
The samples were then left to incubate for two weeks until the next step in the experiment–the

Biology: The Five Processes Of Microevolution
There are five processes to microevolution. There is gene flow, mutation, natural selection, genetic
drift, and recombination. Gene flow is when genes amongst a population are exchanged. It affects
microevolution because it is a change or movement in certain populations that lead to a different
mixture of alleles. Another processes of microevolution are mutations. A mutation is any change in
an organism's DNA. It is an important factor in microevolution because it is the reason for the
development of new genes. Although it is very rare, when mutations are mixed with the act of
natural selection, evolution occurs faster. Natural selection is a process where organisms are able to
adapt to their surrounding environment and survive. The organisms ... Show more content on
Helpwriting.net ...
There is a good chance that macroevolution will affect future generations. The possible affects could
potentially be the creation of a new species of humans. With the possibility of harsh environment
changes over the next several hundred thousand years, perhaps even millions. It is possible that
humans will adapt and dramatically change into something completely different. It is important to
look at our own pass to see how humans have evolved and changed. There is nothing that suggest
that this will not happen in the future. The process of microevolution may shape us over time to
create enough diversity to enable certain populations to adapt to new environments while others
either leave or die, creating a new species in time. Of course, it would take massive environmental
changes and time in order for this to occur, but in all likelihood, it will happen. It has happened for
the past four and a half billion

Color Morphism Lab Report
Sexual selection and genetic color polymorphisms in animals Introduction: Genetic color
polymorphism is an ideal model system, which can be used to study evolutionary stages for
numerous reasons. First, high heritability can be shown from genetic basis that color morphs
provide. Second, separate color morphs can provide visual markers and can be seen in isolated
individuals when observing selection in the wild. With use of morph frequencies, genotype
frequencies can be detected easily and derive allelic frequency modifications over space and time.
There have been numerous Drosophila studies that have used visual eye marker phenotypes to study
evolutionary changes, which have been shown that color morphs can be correlated to strong natural
and ... Show more content on Helpwriting.net ...
Such effect will enhance the heterozygote disadvantage and promote stable polymorphism
emergence as recessive alleles being masked in the process. Genomic architectures tend to favor
speciation by either eliminating or reducing recombination between traits that are correlated with
reproductive isolation. Such changes in recombination rate can occur via synergistic pleiotropy,
which result in magic traits. Magic trait models suggest there is a link between reproductive
isolation and ecological trait. As a result, the ecological trait will produce reproductive isolation as a
by–product and as correlated response. When fitness advantage passes across multiple consecutive
generations, it will affect several phenotypic traits in a certain population, such as: physiology and
behaviors, in addition to the alteration of the population's morph sequences by fitness consistency.
Natural and sexual selection can work together as they do in different color morphs. In general, this
study shows the tremendous effect of natural and sexual selection on the evolutionary process
especially when they act concordantly on a certain trait. As a result, the target population will
experience a stronger evolutionary pressure when the two selections (natural and sexual) work in
one

Analysis Of Nick Lane's Life Ascending : The Ten Great...
Nick Lane's book, Life Ascending; The Ten Great Inventions of Evolution, published in 2009, is an
excellent piece that brings together various elements of life itself, such as, DNA, photosynthesis and
complex cells. However this critique will be based on Chapter 5 of his renown book; Sex – The
Greatest Lottery on Earth. Dr Nick Lane is a biochemist who has won several awards for the
research of evolutionary science he has completed and is known as one of the founding members of
the UCL Consortium for Mitochondrial Research. Each of his four books released were a huge
success and he is still respected for his work and research. All in all, Lane is considered as a source
that is reputable and it is safe to say that his current book being ... Show more content on
Helpwriting.net ...
Despite all this, the question keeps coming back; why is sexual reproduction still the choice of
reproduction or even exist? Why can't all species reproduce asexually?
Without sexual reproduction in humans, offspring would just not be produced as our species have
not evolved to reproduce without the crucial two sex cells from the male and the female. A process
known as chiasmata, the switching of genetic material to create new combinations of chromosomes
for the offspring from the mother and father, is very important as it states that through chiasmata,
sex produces greater variation as the recombination hatches a product that contains genetic
information unlike any other, making offspring that natural selection can work with instead of
against. This process also removes harmful mutations throughout generations through the
'recombination' of chromosomes. August Weismann and Darwin agree on this concept but instead of
believing that sex benefits purely the individual, Weismann stated that it was a benefit to the
population, as the combinations of good and bad genes would be made evenly and would cancel any
benefits for the individual. However, the benefits would only be seen after several generations when
natural selection eventually eliminates the bad combinations. For example, it is beneficial when a
large amount of variation exists within a population

Sex: Annotated Bibliography
Peil et al. (2003) studied this phenomenon in detail. For dominant markers, five different
polymorphic configurations are possible in a single cross when female and male progeny are
considered separately and they found four of them. For 43 AFLP markers, complete co–segregation
between the AFLP fragment and male sex was observed. Twenty–three sex–linked AFLP markers
showed other segregation patterns. There was also recombination between sex–linked AFLP
markers. Peil et al. (2003) found a recombination rate of 25% between sex and the completely
linked AFLP marker loci AGA*GAA510 and AGA*AAT330 on X as well as on Y.
The phenotypic expression of sex in hemp shows some flexibility. Anomalies in flower development
are sometimes observed, such as

Science Behind Technology : How It Was Discovered And...
3. How it was discovered & Science behind technology (455) (6)
SCRaMbLE (synthetic chromosome rearrangement and modification by loxP–mediated evolution)
is a method used to increase the phenotypic and genotypic diversity of organisms1. It relies on the
Cre–loxP system which consists of a Cre recombinase enzyme and a loxP site that directs the Cre
recombinase, making the system site–specific2. The Cre–loxP system was isolated from
bacteriophage P1 where it was described as being a mechanism used by the bacteriophage to insert
plasmid DNA into specific sites of the bacterial chromosome3, as well as recombination amongst
bacteriophages2. The Cre–loxP system was first tested in Saccharomyces cerevisiae (S. cerevisiae)
in 1987 and determined ... Show more content on Helpwriting.net ...
Using SCRaMbLE, it can be determined which combinations of S. cerevisiae genes produce viable
organisms by inserting loxP sites and sequencing the organisms produced as a result. The Sc2.0
project is being undertaken by many scientists across the world, each focusing on a separate
chromosome6. The SCRaMbLe system is utilised to make modifications in the created genome, as
without these induced modifications, the chromosome would be a duplicate of existing non–
synthetic chromosomes6, thus it would not be classified as a synthetic chromosome.
Sc2.0 has not been fully completed as of yet, however many of S. cerevisiae's chromosomes have
been synthetically made, the first of which was synIII, a synthetic version of Yeast Chromosome III,
which is 86.5% shorter than its naturally–occurring counterpart8. Overall 30% of the yeast
chromosomes have been entirely synthesised10, and there is still a large amount of work needed to
be completed to finish synthesising the incomplete synthetic chromosomes, as well as putting all of
the synthetic chromosomes together to make a synthetic yeast organism, where the synthetic
chromosomes have a minimal impact on function and viability. Experiments have been conducted to
determine if they can combine the function of three synthetic yeast chromosomes, synIII, synVI,
and SynIXR, which resulted in a slightly slower growth rate of the cells with all three synthetic
chromosomes11.
SCRaMbLE can be used as a genome

Gene Mapping Essay
Gene mapping is used to map the relative positions of genes on a chromosome using cross over
frequency 1% recombinant frequency is equal to 1 map unit (mu). The order of gene and the relative
distance between them is essential for mapping. Genetic markers are used to determine the location
on the DNA. The study of gene mapping on humans allows understanding the structure, function
and organization of DNA. Whereas on non–humans will provide the basic knowledge for
comparative studies, that is critical to understand for more complex systems. Gene maps are
relevant for industrial and medical senses. This is also known as much cost effective way to follow
generations in short period. Genes involved in genetic inherited diseases will be identified and also
they contribution to the diseases. (gene mapping ).
This process along with Mendel's inheritance study have (mendal pea plant references) largely
contributed to locating genes that give rise to diseases. Austosmal resceeive disesas such as PKU
(phenylketonuria), Sickel cell anemia , CF (cystic fibrosis). Austomal dominat diseases such as
Huntington's disease. It has been found that many diseases are caused by modification of single
genes this is called "oligogenic". This is the case for
Drosophila fly was used in this experiment to study Mendlian inheritance. As Drosophila has a short
life cycle limited days at room temperature it also has a high reproductive rate. This makes research
slightly earier when understanding

Gel Electrophoresis Essay
To enable recombinational cloning and efficient selection of entry or expression clones, most
Gateway® vectors contain two att sites flanking a cassette containing:
The ccdB gene (see below) for negative selection (present in donor, destination, and supercoiled
entry vectors)
Chloramphenicol resistance gene (CmR) for counterselection (present in donor and destination
vectors)
After a BP or LR recombination reaction, this cassette is replaced by the gene of interest to generate
the entry clone and expression clone, respectively.
6) Gel Electrophoresis
Agarose gel electrophoresis is a method of gel electrophoresis used in biochemistry, molecular
biology, genetics, and clinical chemistry to separate a mixed population of DNA or proteins in a
matrix ofagarose. The proteins may be separated by charge and/or size ... Show more content on
Helpwriting.net ...
Nucleic acid molecules which are to be analyzed are set upon a viscous medium, thegel, where an
electric field induces the nucleic acids to migrate toward the anode, due to the net negative charge of
the sugar–phosphate backbone of the nucleic acid chain. The separation of these fragments is
accomplished by exploiting the mobilities with which different sized molecules are able to pass
through the gel. Longer molecules migrate more slowly because they experience more resistance
within the gel. The DNA fragments of different lengths are visualized using a fluorescent dye
specific for DNA, such asethidium bromide. The gel shows bands corresponding to different nucleic
acid molecules populations with different molecular weight. Fragment size

How Africa Learned To Love The Cow Summary
Genetics contribute to every aspect of human life. It determines our phenotypes like eye color or
height and also less visible traits like diseases or in the case of Erika Check's article, lactase
persistence. In the article "How Africa Learned to Love the Cow" Check uses data to show the
convergent evolution of milk tolerance into adulthood and the genetic implications that it poses. By
using genetic information from over 43 different ethnic African groups with 470 people studied in
total, the research conducted was able to discover a never before found example of convergent
evolution in humans that is relatively recent. Lactase persistence is something easily traceable and
highly favored since the inception of sedentary grouping of human populations and animal
domestication. A few questions that arise from this then is how did lactase persistence first start and
why doesn't everyone in the population have the trait?
1. Why can individuals from only some human populations tolerate milk as adults? (biological
underpinning– how lactose tolerance works and weaning process) (continue with how some
individuals mutated, how it arises, high selective ... Show more content on Helpwriting.net ...
They would eventually have a decreased frequency in individuals who are lactose tolerant since
there would be lower selective pressure and therefore lower demand of that trait since evolutionary
there would be no favorability to keep the ability to drink milk. This would lead to increased
intolerance in subsequent generations due to availability of different food and the cessation of dairy
consumption. There is also a possibility that gene flow or other populations moving, mutation or
genetic drift, affecting the allele frequencies allele frequencies of lactase

Drosophila Melanogaster Lab Report
Abstract Genetic variation in Drosophila melanogaster and many other species is dependent upon
recombination events during Meiosis I. In previous experiments, age of females, behavioral stress,
and fluctuations in temperature has had an effect on the frequency of recombination. The purpose of
this experiment was to observe the effects of changing incubation temperature on recombination
frequency by conducting crosses in different thermal conditions of 25°C, the control, and 30°C, the
experimental. Three distinct genes on the second chromosome were observed: black body, brown
eyes, and vestigial wings. The hypothesis of this experiment was that the rate of crossing over
would be increased with elevated temperature. Additionally, gene pairings located near the
centromere of chromosome would be most vulnerable to temperature change, specifically b–vg.
Results from this experiment indicated that there was an overall increase in recombination
frequencies at 30°C. However, ... Show more content on Helpwriting.net ...
S., Boyd, J. B., Carpenter, A. T. C., Green, M. M., Nguyen, T. D., Ripoll, P., Smith, P. D. 1976.
Genetic controls of meiotic recombination and somatic metabolism in Drosophila melanogaster.
Proceeding National Academy of Science 73(11): 4140–4144.
Bownes, M., Roberts, S. 1981. Analysis of vestigialw (vgw): a mutation causing homoeosis of
haltere to wing and posterior wing duplications in Drosophila melanogaster. Journal of Embryology
and Experimental Morphology 65: 49–76.
Flagg, R. O. 2005. Carolina Drosophila Manual. Carolina Biological Supply Company, Burlington,
NC.
Grell, R. F. 1966. The meiotic origin of temperature–induced crossovers in Drosophila melanogaster
females. Genetics 54: 411–421.
Otto, S. P., Barton, N. H. 1997. The evolution of recombination: removing the limits to natural
selection. Genetics Society of America 147: 879–906.
Parsons, P. A. 1988. Evolutionary rates: effects of stress upon recombination. Biological Journal of
the Linnean Society 35:

Outcrossing
Background and Significance: The question of why some organisms reproduce via selfing while
other, often closely related species, reproduce via outcrossing is a long–standing area of interest in
evolutionary biology. It is thought that outcrossing is favored by selection when promotes
adaptation to changes in the environment. Since self–fertilization appears to have evolved recently
and in multiple lineages within Caenorhabditis, this is a particularly interesting and appropriate
organism for studying factors underlying the evolution of reproductive mode. The rate of
outcrossing vs. selfing differs significantly among strains of C. elegans, yet the underlying
evolutionary factors of this choice in reproductive strategy remain poorly understood. The goal of
this study is to dissect the role of one factor, recombination rate, in determining ... Show more
However, it must be considered that a population already well adapted to the laboratory
environment may experience outbreeding depression when elevated recombination rate is coupled
with significant outcrossing. I speculate that outbreeding depression will not be observed in these
short–term experiments with the wild isolates but will likely be observed in the N2 strain. Among
the wild isolates, I predict that the elevation of recombination rate will allow the population to adapt
more quickly to the environment, resulting in an increase in fitness after 100 generations, and this
effect will be proportional to the rate of outcrossing. Dissecting the role of a changing environment
and the degree of initial local adaptation are areas that could be explored as extensions of this

Overarching Research Paper
Overarching topic: Microbial metabolism and genetics
Learning outcomes:
1. Describe autotrophic, heterotrophic and mixotrophic metabolic microbial pathways in general
terms
2. List the constituents of microbial metabolism for food production and human disease
3. Summarize basic genetic exchanges (i.e. transformation, conjugation and transduction) in bacteria
4. Analyze consequences of mutation and genetic recombination
Formative and summative assessments:
1. Formative: Interactive multiple–choice testing system that gives immediate affirming or
corrective feedback to students and enables partial credit allocation for proximate knowledge,
intended to enhance learning rates.
Summative: Multiple–choice exam questions on the heterotrophs, the ... Show more content on
Helpwriting.net ...
Formative: Think–pair–share exercises on how transformation, conjugation and transduction differ
and the relationship between them.
4. Summative: Summarize basic genetic exchanges in bacteria (as described in a learning outcome)
in a Twitter format (i.e. 140–character limit).
5. Formative: Providing students with data from a mutation experiment and ask them to adequately
analyze the consequences.
Summative: Analyzing hypothetical case–studies and evaluating which mutations and genetic
recombination processes may be responsible for them.
Learning activities:
1. Short interactive lecture (15 minutes) on the topic appropriate for both visual and auditory
learners and with incorporated open–ended questions, providing sufficient explanations to help
clarify student thinking.
2. A reading assignment encompassing all the constituents microbial metabolism will be required of
students to study in depth before class, while the worksheet in class will be used to review the
knowledge they acquired and probe any "weak" points.
3. Interactive videos discussing different genetic exchange mechanisms in bacteria will be showed
to students, followed by class discussion and think–pair–share exercises to resolve any
misconceptions about these

Essay On Cosisp
I believe that CRISPR is going to, and already is revolutionizing medicine. The way we fight
disease, cure cancer, and maybe even create new humans. The editing techniques I'm about to
mention allow scientist to modify DNA sequences in the human body and.
So what is CRISPR? We first have to understand where CRISPR comes into play, and that is
genomic editing. Genome editing is where engineered nucleases are either inserted, replaced, or
deleted in a living organism's genome, and genomic editing is done with the help of the system
CRISPR. The CRISPR cas system is an RNA guided nuclease system for targeted introduction of
doubled stranded DNA cleavage. It was originally discovered in bacteria as an acquired defense
against foreign ... Show more content on Helpwriting.net ...
Other vector variations are also available to provide added convenience, such as GFP for
transfection monitoring or lenti–backbone for viral delivery. For researchers who perform mRNA
microinjection or mRNA transfection. The applications for CRISPR Cas 9 are endless.
There are two types of editing that are commonly used: homologous recombination and non–
homologous end joining(NHEJ). Homologous recombination utilizes a repair template The desired
changes, such as gene knock out, gene tagging, and specific mutations, are flanked by left and right
homologous arm sequences. Upon double cross over the desired changes integrate into the genome.
In non–homologous end joining the ends are joined together and introduce random mutations. Both
types are used to remedy double strand breaks (DSBs), but homologous recombination is highly
preferred over NHEJ because this type of editing is extremely error prone. It can delete or add
genetic information and cause chromosomal translocations.
So why aren't we using these mechanisms on humans in order to control our genetic makeup? In the
medical field we see great opportunity to treating and even curing some of the most horrible of
disease, yet we are still hesitant. Just as easy, as it will soon be, to edit genes for healing purposes
scientists, researchers, and physicians will have to embrace the uncertainty that comes with it. The
uncertainty of incorrectly placing DNA, or deleting/adding DNA that

Common Fruit Fly Lab Report
Introduction
Drosophila melanogaster, or the common fruit fly, is used in genetic studies due to a number of
factors. First and foremost, the similarity of D. melanogaster's genome with the human genome.
Research has shown that they share 75% of their genes with us (Prunier 2014). Secondly, they are
easily grown in large quantities as they rapidly reproduce to give many offspring from each cross.
Thirdly, it is fairly easier to conduct genomic experiments and observe both genotypes and
phenotypes using D. melanogaster due to its manageable genome size of 13,600 genes (Adams et al.
2000). In this lab we used linkage making in order to determine the location of three genes located
on the same chromosome of Drosophila melanogaster. These genes ... Show more content on
Helpwriting.net ...
D., S.E. Celniker, and R.A Holt. 2000. The genome sequence of Drosophila melanogaster. Science
287: 2185–95.
Flagg, R. O. 1979. Carolina Drosophila manual. Carolina Biological Supply Co,
Burlington, NC
Lobo, I. and K. Shaw. 2008. Thomas Hunt Morgan, Genetic recombination, and gene mapping.
Nature Education 1: 205
Prunier, R. 2015. Virtual fly genetics.
Skraastad, M., E. Van de Vosse, R. Belfroid, K. Höld, M. Vegter–van der Vlis, L.A. Sandkuijl,
E. Bakker, and G.J. van Ommen. 1992. Significant linkage disequilibrium between the Huntington
disease gene and the loci D4S10 and D4S95 in the Dutch population. Am. J. Hum. Genet. 51: 730–
735.
Sturtevant, A. H. 1913. The linear arrangement of six sex–linked factors in Drosophila, as shown by
their mode of association. Journal of Experimental Zoology 14:

Linked Genetics
Genes located on the same chromosome are linked. They can become unlinked, or separated, in
crossing over with the frequency of separation being higher the further apart the genes are on the
chromosome. The relationship between the frequency of genes separation due to crossing over and
the distance between genes is inversely proportional. That is the further the genes are away from
each–other the more likely they will cross over. The frequency of crossing over, also known as the
recombinant frequency, is directly related to the distance between genes, because the farther apart
two genes are, the more likely a crossover is to form somewhere between them. Geneticists can
utilize this to map chromosomes by doing test crosses for linked genes. ... Show more content on
Helpwriting.net ...
That's to say, if A B and C are near each, it's unlikely that a recombination event will take place
between them, and it's an order of magnitude even more unlikely that two recombination events will
take place. Most people are triple dominant, A – B – C, or triple recessive, A' – B' – C'. However,
sometimes people are A – B – C' or A – B' – C'. But virtually no one is A – B' – C. So to get the A –
B' – C genotype, there would have to be two recombination events. One between A and B and
another between B and C. To get A – B – C' and A – B' – C' you only need one recombination event.
Between B and C or A and B,

Mechanisms of Sex in Escherichia coli
The discovery of the gene transfer mechanisms could be attributed by the work of Lederberg and
Tatum back in 1946. Using Escherichia coli(E.coli) as their model, they proposed the genetic
materia of E.coli could be exhanged via sexual process. In order to prove their hypothesis, they
mutated 2 wild type E.coli strains(K12) using X–ray or ultra–violet radiation to produce Y–10 and
Y–24 mutant strains. The former was auxotrophic to threonine, leucine and thiamin whereas the
latter failed to produce biotin, phenylalanine and cystine[1]. These mutant could only survive in
mininal media plates provided that the aforementioned amino acids are supplied accordingly to each
mutant strains.
Further experimentation was conducted where they mixed ... Show more content on Helpwriting.net
...
transformation and conjugation. The former would imply the presence of unknown transforming
factors which brought about gene mutations that caused the reversion of mutant E.coli strain to wild
type strain. The latter would then suggest that random gene reassortment in new combinations
which required the fusion of bacterial cells in order to exchange genetic substances. Regrettably, no
further evidences were produced to substantiate either one of these models.
In the BIOL2202 bacteria genetics practical, our results can hardly discriminate which sex
mechanism was employed by E.coli to revert back to prototroph as the donor(JC158) and recipient
strands(AB1157) were added into a Erlenmeyer flask and mixed together to facilitate conjugation.
Besides, the reversion could also be attributed to transformation due to unknown transforming
factors which somehow mutated the gene back to wild type configuration. When mixing began, both
transformation and cell conjugation were possible, thus it was hard to differentiate which
mechanism that ultimately leads to the appearance of prototroph.
Given that there were two plausible models, Bernard Davis was able to prove that conjugation was
the underlying mechanism for the unsolved mystery via his U–tube experiment conducted in 1950.
His U–tube was designed with a separation which composed of ultrafine fritted glass disc in the
middle that would only allow

Importance Of Diversity Between Species And Species

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