The document discusses the nematode C. elegans as a model organism for studying Alzheimer's disease. Some key points:
- C. elegans is a useful model organism for neurodegenerative diseases like Alzheimer's and Parkinson's due to its short lifespan, transparency, and genetic similarities to humans.
- Sydney Brenner first introduced C. elegans as a model organism in 1963 due to these advantages.
- About 38% of the C. elegans genome is genetically similar to humans, allowing researchers to study genetic pathways involved in neurodegeneration.
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DORN1
1. DORN1
DORN (Does Not Respond to Nucleotides 1), DORN1, L–Type Lectin Receptor Kinase I.9, LECRK–I.9 are synonymous. According to TAIR
database, LECRK–I.9 is involved in protein–protein interactions with RGD–containing proteins as potential ligands, role in cell wall–plasma
membrane adhesion and involved in Phytophthora resistance. The mutant dorn1 is defective in LECRK I.9. DORN1, binds ATP with high
affinity and is required for: ATP–induced calcium response, mitogen–activated protein kinase activation, gene expression. Ectopic expression of
DORN1 increased the plant response to physical wounding. Choi et.al. (2014) demonstrated that DORN1 is essential for perception of
extracellular ATP and likely plays a variety of roles in plant stress resistance ... Show more content on Helpwriting.net ...
A. tumefaciens (strain LBA4404) carrying pCAMBIA 1200 35S harboring oxDORN1 gen and A. tumefaciens (strain LBA4404) carrying
pCAMBIA 1200 35S empty vector were supplied by Dr. Kiwamu Tanaka. Agro–infiltration on N. benthamiana leaves was made following the
procedure of De Felippes and Weigel (2009) and adapting the O.D. and time of the day for agroinfiltration. Four weeks old N. benthamiana
plants were agroinfiltrated. Three days after agroinfiltration, leaves for inoculated with TSWV. A total of five greenhouse assays were performed
in order to determine the better setup to test effect of oxDORN1 on TSWV levels. The first three were to optimize the experiment, the fourth and
the fifth were to evaluate the effect. The final treatments consisted of a) N. benthamiana inoculated with buffer phosphate; b) A. tumefaciens
strain LB4404 pCAMBIA1200 empty inoculated with TSWV (O.D.600nm 0.40); c) A. tumefaciens strain LB4404 pCAMBIA1200 35s
oxDORN1 inoculated with TSWV (O.D.600nm 0.45) d) N. benthamiana inoculated with TSWV. Three plants per treatment, three leaves
agroinfiltrated (# 5, # 6, #7) and three days after were inoculated. The inoculated leaves were harvested at 3, 7 and 10 days post–inoculation
(dpi) and tested by ELISA. The results of the transient expression of oxDORN1 did not show any differences in the level of N protein
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3. Persuasive Against Animal Testing
Every year alone Europe uses 12 million animals for testing. Just think about it every 10 minutes 137 animals are hurt or abused. Laboratories
get paid to test cosmetics, soaps,and different treatments for cancer and other illness on animals. These animals include monkeys, rabbits,
hamsters, Guinea pigs, and fish. The Animal Welfare Act (AWA), which is for only the U.S.A is supposed to keep all animals safe from abuse,
but really only 5% of the animals are covered, mostly monkeys. Every day all of the animals that are not covered are abused. Animal testing is
very cruel and inhumane and it needs to stop!
Many ask why animals are used to test on. "It's the closest thing to humans that's not human," is what laboratories that get payed crazy dollars to
test on these poor animals. The animals are usually testing the toxicity of medicine. Also they test the effects of different soaps in their eyes.
Animal testing has been successful, it has created cures for 21 cancers and many illnesses, but 100's of thousands of animals had to die when
there is another way. The other way never would have touched an animal, it uses an microchips and a computer software. Its called Microfluidic
chip. It replicates the movement of the bodies organs. Different inputs go into the software and it runs the program and an output shows what
would happen in the body. Also, according to Kara Rogersm from britannica.com, "We can grow human skin cells in glass containers to use to
test toxicity." Using
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5. Model Organism: The Fruit Fly
The fruit fly Drosophila melanogaster is an extensively studied model organism. Its steadfast presence since the early 20th century, has led to
significant findings and contributions in classical genetics, various areas of biological sciences, and biomedical research. This includes the
discovery of the fundamental concept that chromosomes carry heritable traits (Pandey and Nichols, 2011). Its fully sequenced and annotated fly
genome, homology similarity to the human genome, rapid life cycle, large number of progeny, easiness of culturing, and low maintenance
expenses are the primary attributes that make it an excellent model organism convenient for study (Arias, 2008; Pandey and Nichols, 2011).
Even more so, humans and D. melanogaster share ... Show more content on Helpwriting.net ...
It is characterized by a 90% deletion in the structural gene for xanthine dehydrogenase and is deficient in activity of peroxisomal xanthine
oxidase that is pertinent for purine degradation (Beard and Holtzman, 1987). Homozygotes or hemizygotes ry506 also disrupt central nervous
system development, and have no effect on cuticle or abdominal bristle formation (Xiaofeng and Riddiford, 2008). Furthermore, juvenile
hormone (JH) at pupariation results in reexpression of the transcription factor gene, broad, in the epidermis amid adult development, but ry506
does not show the reexpression of broad. This suggests XDH is vital for JH sensitivity on the abdominal epidermis (Xiaofeng and Riddiford,
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7. What A Model Organism?
Abstract In order to understand what a model organism is, we have to take a look into one of the most widely used organisms in genetics;
Caenorhabditis elegans a nematode known for its male and hermaphrodite parts. Also known to be the most useful model organism because it is
transparent, small in size and easy to cultivate. For this experiment we will be analyzing genes that regulate biological processes. The main focus
will be what geneticists' call the forward genetic screen, this technique is used to screen mutant animals for a certain phenotype. It was started by
a man named Sydney Brenner who began with a certain phenotype and discovered mutants of that phenotype, essentially conducting a forward
genetic screen. This technique is used to study genetic pathways that regulate biological functions, allowing scientists to focus on the pathway of
the function of neurons, these neurons are what makes signals of muscle movement. This research can lead to better understanding of human
genes and how to analyze pathways that are responsible for tissue and organ function. Sydney Brenner was able to identify over 600 mutants, for
this lab we have focused on ~9 phenotypes, our given phenotype will be the Protruding vulva (PvL). Figure 1 is the C.elegans life cycle, the
understanding of the nematodes lifecycle will allow for better results, knowing the time it takes for these worms to reproduce can provide us
with the mutants we are looking for. Contents Genetic Mutation in
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9. Factors That Affect Our Soil Affects Them And Their Movements
C. elegans are a nematode a member of the phylum nematode family. They are roundworms with smooth, unsegmented skin and are about one
millimeter in length. C. elegans. The do not have a respiratory and circulatory system, but they do have a hypodermis, excretory system and
muscles.(1) They are model organisms to use in experiments because they have a short life span, which makes them manageable, they are
inexpensive, and most importantly they are transparent.(2) Therefore, whatever you do to them you will be able to see through a microscope. I
conducted a research on C. elegans to test to see how every day fertilizer that we apply to our soil affects them and their movements. When you
are putting fertilizer on your soil you are adding extra nutrients to the soil to make your yard look nicer. Although, if you are not careful you may
also be putting too much fertilizer on your soil which is raising the concentration of all the nutrients in the soil abnormally
Therefore, the reason for my experiment is to see how adding fertilizer may affect C. elegans. This research is important because, if we don't
know what happens if we add fertilizer to C. elegans environment, then we can potentially be killing them. Therefore, if we are killing the C.
elegans, then we are killing the environment itself. My hypothesis on this experiment is that NPK fertilizer will affect C. elegans negatively,
causing them to decrease in motion and repel from the fertilizer.
Methods: One the first day
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11. Alzheimer 's Disease And Its Effects On The Lives Of...
Introduction
Neurodegenerative diseases continue to affect the lives of millions Americans each year, with incidence and prevalence rates ever increasing.
These diseases cause degeneration or death of nerve cells in the brain. These diseases can cause a financial and emotional burden on not only
patients themselves, but also family members and care givers as well. Molecular mechanisms that underlie these diseases have remained
relatively unclear, despite much research. Understanding the mechanisms of these diseases are facilitated by utilizing model organisms to study
pathways involved in neurodegenerative diseases. One such model organism is the Caenorhabditis elegans nematode. The C. elegans
roundworm has displayed usefulness as a template to study neurodegenerative diseases in humans, including Parkinson's disease and
Alzheimer's disease.
C. elegans has shown to be a useful model for the study of Alzheimer's disease. Sydney Brenner first introduced the nematode as a model
organism in 1963 (Brenner, 1974). The small, transparent roundworm is easy for manipulation, with a life cycle of 3 days from egg to adult at 25
degrees Celsius (Brenner, 1974). It is hermaphroditic and self–fertilizing allowing for rapid production of offspring. Its lifespan is between 2 to 3
weeks, which is another beneficial feature for scientific research due to its relatively short timeframe. The C. elegans genome was completed in
1998 and showed that about 38% of worm genes have human
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13. Escherichia Coli : An Ideal Model Organism
Title : Studies of Large RNAP
NusG
70S Transcription
Translation Linking Complex Author : Dominique Gutierrez, Cristina Gutierrez
Vargas,
and Dr. Joachim Frank Abstract Escherichia coli (E.coli) is an ideal model organism. Many mechanisms found in E.coli are resembled in other
species. S10, a protein on the 30S subunit of the ribosome, is highly conserved and found in pathogens, including Pseudomonas aeruginosa,
Staphylococcus aureus, and Streptococcus pneumoniae. S10 has been shown to interact with NusG, a transcription elongation factor, linking the
translational machinery to that of transcription. The coupling ... Show more content on Helpwriting.net ...
Introduction The relatively sudden rise in antibiotic resistance has resulted in the increasing pathogenicity of bacterial infection entailing the
utilization of novel and more universal mechanisms in the development of new treatments. Both NusG and NusE/S10 are
highlyconservedandplayrolesintranscriptionandtranslation(Werner,2012).Sinceits identification as an E.coli transcription elongation factor
involved in N protein phage lambda transcriptional antitermination in 1992 (Li J., et.al), N
utilization substance G, NusG a 20.5 kDa protein has
been suggested toactasadirectphysicallinkercoupling transcription and translation (Burmann et al., 2010). Through NMR and biochemical assay
studies Mooney (2009) found that NusG has two domains connected by a flexible linker that distinctly makeupthecharacteristic functionalities of
NusG. The N
TerminalDomain,NTDcomposedof3alphahelicesand 4 beta strands that form an antiparallel sheet has a hydrophobic pocket by
which it interacts and binds to the β′ clamp helices of RNA Polymerase, RNAP. Through this
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15. Pros And Cons Of The Fruit Fly
Rationale:
Nowadays, the use of animals in vivo, such as Drosophila melanogaster, brings a lot of benefits to understanding human neurodegenerative
diseases and to the discovery of new drugs.
The fruit fly, Drosophila melanogaster, is a practical and powerful model organism that has been used in biomedical research for over a century
due to its large variety of available genetic tools, high reproductive capacity, short generation time, reduced conservation costs, a shared 75%
disease–related genes with humans and its easiness to be worked with at an ethical and legal level.
The larvae of Drosophila melanogaster are documented as being more sensitive than adults, the traditional model.
Neuro Test will take advantage of the larvae's high sensibility to create an automated technic to access motor, sensitive and cognitive function
effortlessly at a large scale and low costs.
This technic has potential to be used in the pharmaceutical industry, directly guiding clinical research and the development of new treatments,
and in the environmental toxicology studies ... Show more content on Helpwriting.net ...
Speed tests will be made with yeast paste bait (1:1 of brewer's yeast in distilled water) placed right in the center of the arena. In the learning and
memory tests, we will use a set of accessories disks alternating between black and transparent areas. The standard behavior of the larvae will be
used to test sensitive function (spatial perception). Centrophobia it's documented as a standard behavior for Drosophila melanogaster larvae,
meaning that when encountered on the center of an arena the larvae have the tendency of rushing to the periphery. But, when larvae are exposed
to certain drugs a change in this standard behavior/normal orientation is easy to detect. Videos will be obtained with a smartphone positioned
slightly above the arena, in a perpendicularly fixed
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17. Informative Speech : Product Testing On Animals
TYPE OF SPEECH: Persuasive Speech
Topic: Product testing on animals
Purpose Statement: Keep from testing cosmetics on animals.
Thesis Statement:
Animals are forced to try products. From forced eating to wearing l 'oreal makeup.
Organizational Pattern: Problem– Solution
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
Introduction
Attention Getter (Capture): Have you ever wished for a rabbit or a guinea pig?
Motivate: Most of the world's common household pets are having cosmetics tested on them.
Introduce the topic: Help save them from this cruelty.
State the thesis: These animals are forced to try products. From forced to eating food to wearing L'oreal makeup.
Preview: In the next few minutes I will... tell you what's happening to these animals and how you can help them.
Body
Main Point 1: First, the problem.
Animals are having products tested on them. Animals like birds, fish, and rabbits. Companies like Sephora 's makeup, Lubriderm lotion, and
Dove's soap. Mice are the most popular for testing in the United States. This is because mice share 98% of human DNA states (proandcon.org),
and they are easier to breed. Even though, chimpanzees share 99% of our DNA. There are only two places where animals can be tested on, the
United States and Gabon. These animals have rights just like us. It's not like they can walk away from this. They are being held against their
will. These animals have never seen the
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19. C Elegans Research Proposal Paper
Michelle Orta
C. elegans Research Proposal
Genetics Laboratory 3452 Section 501
TA: Melissa Lewallen
April 3rd, 2018 Table of Contents
Table of Contents 2
Abstract 3
Introduction 3
Research Hypothesis 3
Method 4
Expected results 4
Figure and Tables 4
Bibliography 5 Abstract This is a brief description of the hypothesis and the goals of the experiment. It should indicate what questions you, as
a researcher, will be seeking to answer.
Introduction
The nematodes Caenorhabditis elegans are hermaphrodites, meaning they have both the female and male reproductive organs. In fact, C. elegans
produce sperm that is stored in both the spermatheca and oocytes. There is an egg laying defect that can occur in C.elegans. The effect ... Show
more content on Helpwriting.net ...
A forward genetics screen occurs when one starts by determining a biological process of interest, produces a mutagenized population, screens
for phenotype of interest, analysis a mutant with a specific phenotype, maps the gene of interest, and conducts more screens to identify other
genes that are associated with those mutants. And a reverse screen is when one has the analysis of a gene and studies the phenotype associated
with it when it is mutated. To complete this experiment a forward genetics screen is needed. The materials needed are C. elegans, 20 plates to
place and transfer the worms, 20 mini plates to place and transfer the worms, a microscope to view the worms, a glass pipette and a piece of
platinum wire to create a worm pick, a bunsen burner to sterilize the pick, a notebook and pen to record the data obtained, and a lock to secure
our experiment. The purpose of this experiment is to obtain multiple mutagenized C. elegans and allow the P0 generation to grow to a F2
generation and observe if there were any egg laying phenotypes present. To complete this experiment, I would first place a single mutagenized
N2s in each of the POA1–POA5 plates. After 12–24 hours have passed and the eggs have been laid, I would move the 5 adult worms who were
originally placed in each of the POA1–POA5 plates to POB1–POB5 plates according to their number. After the PO generation have grown a
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21. How To Write A Persuasive Speech On Animal Testing
Good morning Queensland youth parliament and Mrs Jans, Imagine spending your entire life as a hospital patient or a prisoner. If you can do
that, then you can begin to approximate the life of an animal in a laboratory. What happens to you can range from agonizing to deadly–and you
are helpless to defend yourself. Over 7 million animals in Australia are used for scientific testing. This includes–dogs, rabbits, pigs,
chimpanzees, and much more. Using animals for testing becomes more disturbing when its effectivity is far less than its cost which includes
animal's lives, our tax dollars, and time. So ask yourself doesn't this undermine our civilization, doesn't this question our humanity, and doesn't
this throw us back to the era of Roman gladiatorial cruelty?
The question is not, can they reason, nor, can they talk. But, can they suffer? Asked James Blueberry. Which brings me to my first point that
scientific testing on defenseless animals results in emotional, physical harm and ... Show more content on Helpwriting.net ...
Firstly, I have stated that animal testing results in emotional and physical harm, then I discussed on growing scientific evidence of how
unnecessary, ineffective, and dangerous it is to use other species for the study of human diseases. What makes this even more alarming is that
57% of respondents in a survey about the ethics code of conduct were not aware that animals are used in experimental research. You can take
action to prevent more harm on animals by purchasing products from companies that are cruelty–free, write to your favourite cosmetic and
product companies which do use animals and urge them to go cruelty–free. If your high school or college conduct animal dissection, explain
how it is unethical and harmful to the environment, and that there are a multitude of superior alternatives. We have to put end on animal testing
if we want to reach the peak of human integrity and
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23. Helicase Drug Therapy Case Study
In the case of Helicase–primase drug therapy, there are drugs candidates that are already past the pre–clinical stage of development. The mode of
action for Helicase–primase drug therapies involves inhibiting viral DNA replication as by targeting down the DNA polymerase complex. In
contrast to current therapies that target the DNA pol gene either directly or through nucleoside analogs. This offers a better strategy for dealing
with a potential HSV infection in a immune–compromised host by not allowing the virus to replicate potentially resistant progeny (11). Clinical
trials have been conducted with HSV targeting drugs ASP 2151 Amenamevir, and AIC316 Pritelivir to evaluate their efficacy and safety in HSV
infections. ASP2151 is a non–nucleoside, ... Show more content on Helpwriting.net ...
Within cell culture it was shown to be 10 times more potent than Acyclovir (11). Phase I of the clinical trials showed the HSV replication was
inhibited within the tested dosing region. It was also concluded the drug stayed in its active form up to 80 hours, far greater than Acyclovir with
no reported negative side effects (1). Within the Phase II placebo controlled trial it was reported that viral sheading and lesion rates were
decreased in a dose dependent manner. Even though the trial was considered small with only 156 subjects, no adverse effects or viral resistance
was reported. Clinical isolates have remained treatable by Pritelivir, but their have be instances for resistance selected for in tissue culture (14).
As for updates for resistance, one mutation has been reported in the helicase gene although this has remained in cell culture (15). Although cell
culture does have a higher tendency to select for resistance, this dose raise the issue of utility for the novel drug down the line. AIC316 is
expected to enter into into Phase III of the clinical trials within the near future. With the clinical trials still proceeding on AIC316 safety is still
being evaluated, and strategies are still being devised. All options are being investigated such as combination therapies with current therapies to
decrease the chance of resistance
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25. Animal Testing Disadvantages
Animal testing
Recently, there is an increasing number of methods, which are used to test medicine and beauty products, are animal testing. In this case,
numerous animals are tested in the experiment. However, in laboratory tests,animal experiments still have defects that need to be solved.
Additionally, the animal testing is a defective method, but it still widely used in normal life, which is utilized to get the result of new medicines
and feedback of cosmetic products. On this basis, a number of people have started to consider whether it is inhumane to test on animal, however
other people believe this is effective for creating new medicine to heal miscellaneous diseases. This essay will discuss some advantages and
disadvantages of the animal testing. Nevertheless, most of new medicines which are created still need testing on animal. Research done by
Garattiui and Grigusschi (2017) displayed that when science and technology has not yet reached a certain level of advanced conditions, animal
experiments are still the main approach to find out the solution of diseases in treatments. There are plenty of benefits about using animal testing
to test new medicines and cosmetic products. The main advantage of animal testing to test medicine is that it can carry out more experiments in
shorter time. This is because of most of growing up period animal is shorter than human. Ostergaard et al. (2010) indicated that when using the
animal experiment to design test models, it needs
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27. C. Elegans Analysis
Dr. Bruce Wightman reeled in an overwhelming number of students, professors, and biology enthusiasts with his talk about his charming
nematodes, Caenorhabditis elegans. Dr. Wightman's experiment involved genetically analyzing a new sleep circuit in C. elegans. He initiated a
discussion about a topic all college students can relate to: sleep. Animals (including humans) love to sleep, but why? Because it allows time for
the brain to clear of any toxins, to produce new cells, and to consolidate new memories. Introducing his work, Dr. Wightman familiarized his
audience about the glamorous and underappreciated C. elegans. The nematode, C. elegans, is the first multicellular organism to have its genome
sequenced. This phenomenal organism has simply
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29. Radiation Therapy Research Paper
2.3.2 Respiratory Gating for Radiation Therapy
Respiratory gating techniques are used to track the tumor motion in uenced by respiratory cycles during external beam radiation therapy in order
to ensure tumoricidal dose to the target site while avoiding healthy normal tissue toxicity Vedam et al. (2003); Kini et al.
(2003); Ford et al. (2003); Kubo et al. (2000); Vedam et al. (2001); Mageras et al. (2001);
Wagman et al. (2001); Mageras and Yorke (2004). The word gate is referred to as a window of the respiratory cycle that is chosen to deliver the
radiation beam that maximizes the radiation dose received at the target site. The three criteria that are considered when designing the gated
region of the respiratory cycle are: The window during respiratory cycle
that ... Show more content on Helpwriting.net ...
Two important components that are considered when analyzing respiratory motion patterns are phase and displacement. The beam is red at the
target site depending on the phase or displacement windows chosen during the respiratory motion. Due to the gated technique, the overall
treatment process takes longer when compared to the conventional methods of administering radiation therapy.
The ratio between the gated beam delivery and the overall treatment time determines the eciency of the treatment called duty cycle. However,
even after the gate has been optimized for a respiratory cycle, there exists minimal tumor motion called the residual motion Berbeco et al.
(2005). To optimize the gateing technique that improves the therapeutic ecacy of radiation therapy and provides patient safety, a balance
between the two (duty cycle and residual motion) needs to be met. The location and the size of the gate are dependent on the tracking of the
target site or host organ by means of internal and external surrogates, internal and external markers or markerless
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31. Arabidopsis Thaliana
Science is a study that prides itself in being in being an intellectual subject, it would only be right that its representatives (professors in this case)
be efficient when describing subjects that have a large area to cover. This requires using easier concepts to understand and that can be applied to
a greater area. One way of doing this is through organisation. If you were a taxonomist, would you start at describing animals by every different
Genus and Species? No! You would start at their Kingdom and Phylum, then work your way down. Every one of these different species is an
excellent representation of a broader group of life. These seven are vast in the number of different species they represent.
Escherichia coli, also known as E.coli is ... Show more content on Helpwriting.net ...
80 years ago this animal was able to provide a definite proof that genes are carried on chromosomes. By editing the DNA of this animal,
scientists noticed that certain areas of the fly grew differently (a leg on its head) causing mutant flies. With this information, they were able to
understand better the cause and effect from the genetic instructions encoded within the chromosomal DNA to the structure of the adult
multicellular
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33. C. Elegan Research Paper
Introduction
C.Elegans are roundworms or threadworms that are 1mm in length and found living within soil around many parts of the world, these C. Elegans
thrive on rotting vegetation where it can survive, feeding on microbes such as bacteria, these C. Elegans are non–infectious, non–pathogenic and
non–hazardous. They are of a long cylindrical shape that looks rather tapered at each end. These worms are found in both aquatic and terrestrial
free living environment's.
C.Elegans also known as Caenorhabditis Elegans are a nematode which is a member of a phylum nematode family. Majority of these nematodes
are males the rest are known as hermaphrodites, which are a species of having both sexes to be able to keep up the reproduction at a good
balance. ... Show more content on Helpwriting.net ...
Elegans mutations are found to be well maintained within the ISS Insulin/IGF–1 pathway that can have a lead on a longer lifespan extension and
this can help with age related diseases along with the improvement of health in later life, This is very important in the understanding of these age
related neurodegenerative diseases because it will help with understanding of how people/patients could then go on to being helped with these
diseases as well as along with tumour formations patients, These functions are looked at closely by the FoxO transcription factor known as
DAF–16 using microarrays, bioinformatics predictions as well as SAGE ( serial analysis of gene expression) and DAF–16 is located
downstream from the ISS Kinase cascade. Looking at how the DAF–16 target gene along with testing its functions has been a long process of
over 10 years in the ageing
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35. Animal Experimentation For Medical And Cosmetic
Every year, more than 100,000,000 animals, containing mice, rats, frogs, dogs, cats, rabbits, hamsters, guinea pigs, monkeys, fish, and birds die
in the United States facilities for the use of chemical, food, drug, and cosmetics testing (PETA). Animal experimentation pertains to the
experiments and procedures that are performed on living animals for insight into many diseases, the effectiveness of new medications,
examining the health effects on humans because of products, environmental safety for industry and consumer products including household
cleaners, cosmetics, pharmaceuticals, food additives and agricultural and industrial chemicals (Humane Society International). Animal
experimentation for medical and cosmetic use is inhumane ... Show more content on Helpwriting.net ...
In this test rabbits are held down with clamps forcing their eyelids open, this can be for several days, this causes them to be unable to blink the
cosmetics being tested away (Holden, Constance). The LD50 or lethal dose 50 test is done to determining the dose of a chemical that is needed
to kill 50 percent of the animals that are being used in the experiment (Crooks, Richard M). In a study done by Humane Society International,
animals are regularly subjected to forced inhalation, force feeding, water and food deprivation, extended periods of being restrained, the
purposely causing burns, cuts, and other wounds to study healing processes, the infliction of pain to study its effects and how to alleviate it, and
the killing using carbon dioxide asphyxiation, breaking of necks, and decapitation (Culliton, Barbara J). This pain that is inflicted on these
animals causes the experiments that are being done on the animals to be cruel and inhumane. Because of the inhumanity many scientists have
come up with alternative testing methods that do not include animal cruelty. The legality of this practice should be seriously questioned because
on the amount of inhumanity the innocent animals receive. By using alternative testing methods scientists can get the same data about the
products being tested without including animals. In these
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37. Zebrafish Embryos
Mice and rats have been the most common model organism that used for research. Recently, the zebrafish (Danio rerio) has emerged as one of
the most popular animal model in different area of research such as developmental biology, genetics, and pharmacology (Liu et al., 2010; Eisen,
1996). Compared with other animal models, the zebrafish has numerous advantages that make them valuable as an animal model. The zebrafish
has a small size (adult ~ 1– 1.5 inches long) and short generation time (about 3 months). In ideal condition, a female zebrafish can produce 100–
200 eggs at weekly intervals, which can allow performing assays that required a large number of subjects. The zebrafish embryos undergo rapid
external developmental within 2–4 days, and
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39. Biofuels And Alternative Sources Of Energy
Introduction Biofuels, derived from living organisms rather than petroleum–laden rock, are the focus of current energy research. The need for
biofuels and alternative sources of energy will be necessary as the earth's resources begin to diminish. In cohesion with this concern, the current
uses of fossil fuels are a concern as the environment pays an incredible toll for our overuse of this resource. Many have attempted to replace
petroleum fuel with the first generation biofuels would require diverting farmland and crops for biofuel production, causing economic and
ethical problems and competing with world food supply (Zhang et. al., 2011). The production of these biofuels have a negative effect on the
environment, as a backdrop of rising crude oil prices, depletion of resources, and political instability in producing countries, only biomass has
the potential to replace the supply of an energy hungry civilization (Antoni et. al., 2007). This is proof that it is crucial to begin to create biofuels
that have a lesser negative impact that can sustain the energy demands that we have today. Currently, as seen in the table, microbes have been
proven to produce ethanol, biodiesel and hydrogen, which are all sources that can be used for producing renewable fuels. Due to their limited
demands on the environment they prove to be an excellent candidate for a successful biofuel.
Many of the biofuels produced from microbes are done so by varying organic pathways in order to
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41. Should Animals Be Used For Medical Research?
Should animals be used in medical research?
Should animals be used in medical research? Some people say that after so many historical experiences, this is beyond dispute, but I think this is
the opposite. With the medicine science and technology developed, the uses of animals in experiments are become more controversial. With the
technologies developed, human beings become more powerful and the intention to protect other creatures will be stronger and stronger. In fact,
most of the time, some medical researchers are often said to be cruel by those people who want protect the animals. The mainly reason is that the
medical researchers make the medical progress at the cost of sacrificing animals.
Some people hold the idea that we can replace the method of animal experiments, such as use the method of design model from the molecular
level. For example, in the treatment of some serious illness, using animal experiment has missed a lot of treatment. If we modified the illness in
molecular level, some diseases can be cured.
From the point view of medical researchers, animals used in medical research cannot be replaced. Even if there are really a lot of alternatives to
replaced animal testing method, from the medical point of view, these methods can seldom be used for tremendous application. First of all, how
can we make people trust the new method? Then, even if the computer can make the experimental model, the final tests still need living body.
Without the living body, how do
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43. Why Companies Must Reconsider Their Use For Cosmetic Industry
Mac, Estee Roder and ). if you are woman and interested in cosmetic, you will be familiar to the name. you may be using the products or want to
get it. Cosmetic industry is the one of the hot industry in entertament. over 000 compnay release the products in the world and – 소비 시장의 결
과. when I chose the new cosmetic, I am always looking what it include and what color it is. I naver consider how the lipstic and mascara are
making. The brand are doing the animinal testing and tons of rabits and dogs are suffering for the products what we buy without any guilty. In
the 2007, EU prehibit the aninmal testing for cosmetic industry. They insists that –––.––––. I agree with EU oppinion, animal testing is the 가혹
행위 to the living –– and morlly woring and it must stop.
There are also legal reasons why companies must reconsider their use of animals in toxicity testing. Within Europe, the cosmetics industry can
no longer manufacture or market products that have undergone animal tests [2 ], and this has been followed by a geographical ban in India
[12 ], with Australia and the US possibly following suit (www.alp.org.au/cosmeticstesting ; www.congress.gov/bill/113th–congress/house–
bill/4148 ). Other regulations that govern the production and sale of chemicals, particularly in Europe, also stipulate that animal studies should
only be carried out as a last resort [3 ,13 ,14 ]. Considering that products are now developed for global marketing, businesses are being
increasingly compelled to
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45. Photosynthesis Lab Report
2. In this experiment the effects of exogenously applied RA on early neural development of zebrafish embryos were observed. It included
immunocytochemical and histochemical analysis of the developing embryos along with quantitative analysis of their anatomy. Knowing that RA
is a positional signaling molecule, they wanted to observe the changes that occur to the anatomy of the zebrafish embryos at different stages
when exposed to RA. Embryos at 50% epiboly and midgastrula stage were exposed to RA concentrations ranging from 10–9¬ to 10–6 M, and
embryos at early and late gastrula stages were exposed to RA concentrations of 10–7 M. For immuniohistochemical analysis, antibodies 4D9,
HNK–1, and MZ15 were used, HNK–1 was used as a marker of neural crest migration, MZ15 in labeling notochord tissue, and 4D9 in
identifying engrailed ... Show more content on Helpwriting.net ...
The RA treated embryos at 50 % epiboly were observed to have affected brain structures that are derived from the neural tube and affected
peripheral neural structures in the head derived from the neural crest and placods. Quantitative analysis of the anterior structures via
acetylcholinesterase stain showed that 10–9¬ M RA has little to no effect on the embryo whereas 10–8 and 10–7 M RA give rise to discernable
abnormalities. 10–6 M RA was essentially toxic. At 10–8 and 10–7 M concentrations of RA, the position of the anterior margin otocyst with
respect to the eye is roughly halved, and the notochord also moves more anteriorly. There are no significant changes in the development of the
midbrain caudal hindbrain, and otocyst, however the rhombomeres cranial to the otocyst are abnormal in most cases. With a RA concentration of
10–6 M, no structures could be discerned in the head, nearly all features were under/not developed, and the forebrain, midbrain, and hindbrain
neurons were not differentiated. Eyes and otocysts were not developed and the tail was also
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47. The Use Of Nanopolymers For Biomedical Purposes
Statement of the problem:
The driving forces behind this work are related to the increased use of nanopolymers for biomedical purposes. Charged and neutral polymers are
routinely used for gene and drug delivery. However, limited studies are performed to test their safety. Therefore, the originality of this work lies
in its attempt to evaluate the toxicity of three widely used polymers for delivery of chemotherapeutic agents. Furthermore, we aim to establish
efficient methods for nanotoxicity testing through comparing the results of three different models ( 2D, 3D invitro cell cultures and invivo
zebrafish embryo)preparing these materials for clinical application.
Abstract
Nanomaterials exhibit a wide range of applications in different aspects of human life . In biomedical fields, nanoparticles are packaged into
different nanocarriers for drug and gene delivery especially for improving the delivery of chemotherapeutic agents to tumors. However, no
sufficient data that detect their toxicity. In the present study, the toxicity of three different polymers that represent promising drug carriers will be
evaluated using 2D, 3D cell cultures and zebrafish embryos. The polymers to be studie include the well–known cationic transfection agents
Poly(ethylenimine) (PEI) and poly(ethylene glycol) (PEG) for their established cytotoxicity as well as the uncharged drug carrier material
pHPMA (i.e. poly(N–2–hydroxypropyl) methacrylamide), Poly(ethylene glycol)–b–poly(N–(2–hydroxypropyl)
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49. Describe The Importance Of Zebrafish
A small aquatic vertebrate, the zebrafish (Danio rerio) is rapidly becoming a new popular model organism in biomedical research.
The importance of Zebra Fish:
Zebrafish can be used in research as an alternative to mammalian species. It has been successfully utilized in developmental biology, a discipline
that often employs molecular biology and genetic methods. As a result of the past three decades of intensive investigation with zebrafish, this
species has become one of the favourite model organisms of geneticists. It is a complex organism with brain anatomy, neurophysiology, and
molecular characteristics like nucleotide sequence of its genes are highly similar to those of other vertebrates including mammals. On the other
hand, it is small, easy and cheap to maintain in the laboratory and has been highly amenable to high–throughput screening (e.g. forward genetic
or drug ... Show more content on Helpwriting.net ...
Zebrafish are able to withstand much higher levels of chemical mutagens that can be tolerated by rodents so it is possible and easy to induce a
much higher density of mutations in their genome.
Zebra Fish in Behavioral Study:
Zebrafish (Danio rerio) have served as animal models in behavioral neuroscience and behavior genetics for the past three decades. They are
becoming increasingly popular in biomedical research, sharing substantial genetic and physiological homology with other vertebrate species.
When assessing certain behavioral measurements, utilizing adult zebrafish models may represent another promising approach.10, 11, 12
Recent research has demonstrated the suitability of adult zebrafish to model some aspects of complex behavior. Studies of reward behavior,
learning and memory, aggression, anxiety and sleep strongly suggest that conserved regulatory processes underlie behavior in zebrafish and
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51. Roundworm Research Paper
Nematodes, also known as roundworms due to their round cross–section, are parasites that can affect both domesticated and wild animals
(Bassert and Thomas 451). The roundworms that are common in dogs are Ancylostoma caninum, Toxocara canis, and Trichuris vulpis (Bassert
and Thomas 451). The roundworms that are common in cats are Ancylostoma tubaeforme, Dirofilaria immitis, and Toxocara cati (Bassert and
Thomas 451). Dirofilaria immitis and Toxascaris leonina can affect both dogs and cats (Bassert and Thomas 451). Baylisascaris procyonis can
affect both raccoons and dogs (Bassert and Thomas 454). Roundworms can live in many of the organs and systems of the body, such as the eye,
gastrointestinal tract, urogenital system, circulatory system, ... Show more content on Helpwriting.net ...
Puppies and kittens should be dewormed in 2–week intervals from 2 weeks of age to eliminate the shedding of eggs (Bassert and Thomas 453).
Dams can be dewormed or given monthly anthelmintic or heartworm preventatives before breeding (Bassert and Thomas 453). Prevention
Control Feces removal and cleaning the kennels should be done daily to prevent infection (Bassert and Thomas 454). Sandboxes should be
covered when they are not being used (Bassert and Thomas 454). Stopping pica in children, removing feces, enforcing leash laws, and using
proper hygiene and handwashing can help prevent infection in owners (Bassert and Thomas 454). Prognosis Public Health Significance
Prognosis is good with treatment in animals that are not extremely debilitated. Young children living with puppies or kittens may be susceptible
to visceral larva migrans (VLM) and ocular larva migrans (OLM) (Bassert and Thomas 452–453). The child ingests the second stage larvae
(infective) which migrates through the lung or liver (VLM) or the eye (OLM) (Bassert and Thomas 453). Parents need to be cautious of places
where children can ingest the infective eggs, such as playgrounds with dog or cat feces and uncovered sandboxes (Bassert and Thomas
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53. Animal Testing and Researching Essay
Animal Testing and Researching
Animal testing is supported by some, but opposed to others. The growing number of animals used in research differs among the different
countries. The fruit fly and nematode are the most used animal in testing. However, the most common mammals used in animal research are
mice and rats. Shaved albino rabbits and guinea pigs suffer severe testing for skin irritancy and eye irritancy. Though the usage of non–human
primates are outlawed in some countries, the U.S. still finds the need to use them. The U.S. government uses tax dollars for testing pesticides
and flourine products on animals.
Animal testing has been a subject of controversy throughout the years. Though it may seem like a ?cruel and unusual ... Show more content on
Helpwriting.net ...
These small rodents are easy to handle and raise, thus used in large proportions. Mice and rats can be tested for various results. Since mice share
ninety–nine percent of their genes with humans, believe it or not, they are considered the ?prime model of inherited human disease?. In addition
to genetics, rats and mice are used to understand how different organisms interact with each other in the same environment. (Wikipedia) They
are used for the study of human cancers and testing of new treatments because of its immunodeficiency status, allowing human tumors to be
grafted on without rejection. (UCCA) Some rats are even used for studies of brain function, commonly memory and social behavior. The safety
of drugs, vaccines, chemicals, and products are also tested on mice. (Wikipedia)
Though rats may seem like the most popular lab animal, the most animals used in testing are actually invertebrates, especially the fruit fly,
Drosophila melanogaster, and the nematode, Caeharbabditis elegans. These, like rats, are very cost efficient and can be studied in a large
number. Their short life cycle also makes it convenient for genetic studies. Many invertebrate species are not protected under animal research
legislation, so the number of invertebrates used in research is unknown. (Wikipedia)
Shaved albino rabbits and guinea pigs are generally used for skin irritancy testing. Though test tests
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55. Natural and Sexual Selection of Vestigial and Wild Type...
Natural and Sexual Selection of Vestigial and Wild Type Drosophila melanogaster
Abstract
In this experiment, vestigial flies as well as wild type flies were used to create some diversity as well as test one of our hypotheses. Our
hypotheses are as follows; 1) The wild type flies will have a greater relative fitness compared to the vestigial flies based on only sexual
selection. The wild type has a relative fitness of 1 since it has fully functional wings. Vestigial Winged flies are not as sexually appealing since
their wings are not functional and the wing movement is a vital part of their mating ritual. 2) The vestigial fly will have a greater relative fitness
when considering both sexual and natural selection. With the presence of ... Show more content on Helpwriting.net ...
With the presence of natural selection (fly paper hanging from top of cage) posing a larger threat to the wild flies b/c they can fly better, this will
allow vestigial flies to prosper better.
Materials and Methods
To set up this experiment, two twenty–five gallon aquariums, 3 petri–dishes, 200 flies, rotten bananas, and yeast were used. The bananas chosen
to be an accelerant for the growth of the yeast and were frozen so they would be easier to cut. The yeast was used because the drosophila
melanogaster prefer this as a food source. The vestigial and wild type flies were sexed (to determine their sex), sorted, and counted. An initial
population size of 100 total flies was decided so that it would be easier to determine the phenotypic percentage of the total population. Fly paper
was placed in one of the sets of cages to impose a method of natural selection as well as the sexual selection which is being solely tested by the
other set of cages.
It was decided that there would be 80 vestigial flies and 20 wild type flies to total to an initial population of 100 drosophila. Next, the flies were
anesthetized flies using Fly Nap. The flies were counted out to reach desired ratio, sexing the flies making sure there are equal amounts of males
and females to be sure there is ample individuals to allow successful mating. The fly's food was prepared by taking a frozen rotten banana,
cutting it in half, mashing up the banana meat, and mixing yeast into it. The
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57. Caenorhabditi Elegans Research Paper
Dauer Stage Development in C. elegans
Yirui Chen
Caenorhabditi elegans?has become an important organism in which to study processes that go awry in human diseases since over 50 yeas ago
when Sydney Brenner had the foresight to develop the nematode (round worm)?Caenorhabditis elegans?as a genetic model for understanding
questions of developmental biology and neurobiology. There are several attractive features that make Caenorhabditi elegans?an ideal organism
for the study of gene regulation and function. First of all, C. elegans is a eukaryote, which means that it shares cellular and molecular structures
and control pathways with higher organisms. At least 38% of the C. elegans protein–coding genes have predicted orthologous in the human
genome, ... Show more content on Helpwriting.net ...
Mutations in the daf–2 insulin receptor?like gene or the downstream age–1 phosphoinositide 3–kinase gene extend adult lifespan by two to
threefold. To identify tissues where this pathway regulates aging and metabolism, we restored daf–2 pathway signaling to only neurons, muscle,
or intestine. Insulin–like signaling in neurons alone was sufficient to specify wild–type lifespan, but muscle or intestinal signaling was not.
However, restoring daf–2 pathway signaling to muscle rescued metabolic defects, thus decoupling regulation of lifespan and metabolism. These
findings point to the nervous system as a central regulator of animal longevity. (Wolkow et.al,
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59. A Model Organism Is A Non Human Species
A model organism is a non–human species that is extensively studied to understand particular biological phenomena, with the expectation that
discoveries made in the organism model will provide insight into the workings of other organisms. Model organisms are in vivo models and are
widely used to research human disease when human experimentation would be unfeasible or unethical. This strategy is made possible by the
common descent of all living organisms and the conservation of metabolic and developmental pathways and genetic material over the course of
evolution. Studying model organisms can be informative, but care must be taken when extrapolating from one organism to another.
In researching human disease, model organisms allow for better understanding the disease process without the added risk of harming an actual
human. The species chosen will usually meet a determined taxonomic equivalency to humans, so as to react to disease or its treatment in a way
that resembles human physiology as needed. Although biological activity in a model organism does not ensure an effect in humans, many drugs,
treatments and cures for human diseases are developed in part with the guidance of animal models. There are three main types of disease
models: homologous, isomorphic and predictive. Homologous animals have the same causes, symptoms and treatment options as would humans
who have the same disease. Isomorphic animals share the same symptoms and treatments. Predictive models are similar
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61. How Mutagens Affect Our Organism Caenorhabditis Elegans (...
Caenorhabditis elegans Proposal
Josephine Sinamano
Janak Sunuwar
November 6, 2015 Table of Contents
Abstract...........................................................................................1
Introduction......................................................................................1
Specific Aims....................................................................................5
Methods..........................................................................................6
Projected Results...............................................................................7
Discussion........................................................................................7
Bibliography....................................................................................
Abstract
Throughout the years scientists and researchers have done many studies that pertain to how mutagens cause mutations in genes. They have also
studied these mutations to see if they transfer to the next generation or whether the DNA repairs the mutation before it gets passed on. In this lab
we will be looking at the mutagen ethyl methanesulfonate (EMS) and how it will affect our organism Caenorhabditis elegans (C. elegans). EMS
is known to be mutagenic and carcinogenic because it can produce significant levels of alkylation at oxygens of guanine and in the DNA
phosphate groups. It can also produce GC to AT transition mutations and vice versa. There has also been evidence that EMS is able to break
chromosomes (Sega). We hypothesize that when we expose the C. elegans to the EMS, a mutation will occur on the DNA that will cause a
phenotype to occur in the organism that is different from the wild type. Our goal is to be able to locate the mutation on a gene, and match it to
other kingdoms to see if they are homologous to other genes. This is beneficial to us as humans
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63. Model Organisms Essay
During the course of the past thirty years, the study of model organisms has become more significant in the study of embryological
development. A model organism is a species that is easy to cultivate and monitor in a laboratory environment and is used to represent broad
groups of organisms. Examples of successful and important model organisms include the Ascidia, Zebrafish, and Medeka species. Through
intense researching of these organisms, scientists have been able to gain valuable insight into the developmental processes of many complex
vertebrates, including humans.
Model organisms are used to study embryonic development for several reasons. These organisms have shared characteristics including short life
spans and generation ... Show more content on Helpwriting.net ...
2001).
Through research of the embryonic development of the ascidians, scientists were able to better understand the vertebrate gene function and
regulatory networks of several processes. The ascidia genes involved in the formation of the notochord, which were shown to be analogous to
those of tadpoles, and were consequently mapped in order to obtain information regarding gene function in vertebrates. In addition, the
developmental processes in ascidia embryogenesis were studied in great detail, leading to advances in the conception of the regulatory network's
involvement in governing notochord differentiation and also the process leading to the formation of the tail (Corbo et al. 2001).
The zebrafish, another marine model organism, was also selected due to its short life cycle and rapid embryological development. Moreover, the
zebrafish have nearly transparent embryo cells, making the embryos easily accessible, and allowing developmental events to be easily observed.
As a result of numerous similarities in development when compared to other vertebrates, the zebrafish has solidified its position as a model
organism. Most importantly, the zebrafish is an effective model organism because both experimental embryologic methods and genetic analysis
can be easily applied to it (Grunwald and Eisen 2002).
Due to experimentation with the zebrafish, scientists have been able to gain insight into the formation and function of individual tissues, organ
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65. Essay on Animal Testing
Every year, animals are subjected to cruel and unnecessary experimentation. According to the USDA, between 1990–1997 research labs
registered with the USDA reported killing at least 12,895,885 dogs, cats, primates, guinea pigs, hamsters, rabbits, bears, armadillos, squirrels,
wild rodents and other species. This doesn't include non USDA registered labs (Wikianswers). Lab animals are cut up and tortured to death all
in the name of science. How can we as fellow animal species continue to allow this to happen? Animal testing is a callous and barbaric practice.
It is unreliable, and there are newer ways to test products that do not involve slaughtering animals. Animals have no voice and cannot defend
themselves, so we need to take a stand ... Show more content on Helpwriting.net ...
Yet there have been many tests where different species have different reactions to the same chemical. According to the Humane Society, Only
50–70% agreement between rat and mouse test results for the same chemicals (Animals in Research). Obviously different chemicals are
going to react differently in different species. So how can we expect to know how a human will react if most animals react differently? One of
the most famous examples of inaccurate testing would be the release of Thalidomide as a safe sedative for pregnant or breastfeeding women.
Despite extensive animal testing which showed that the drug was safe, thousands of children were born with severe birth defects. Another
example would be Clioquinol. Supposedly, this drug cured diarrhea, but in humans it actually caused it, and in severe cases, death (CAAT–
Against Animal Testing). It is also thought that animal testing will help find a cure for cancer. Billions of dollars have been spent, and so far
there is nothing to show for it. According to the National Cancer Institute there are two main reasons why animals do not accurately help with
cancer research. 1. Animals and humans do not get the same diseases. As a result, animal research focuses on artificially inducing symptoms of
human cancer and attempting to treat those symptoms. 2. Experimental drugs and treatments that have been found effective on animal models
will not necessarily work in people (CAAT–Against Animal
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67. Roundworm Essay
Roundworms are smooth–skinned, unsegmented worms with a long cylindrical body shape tapered at the ends. They include free–living and
parasitic forms and have many different ecological roles. My research paper sheds light on roundworms and specifically Caenorhabditis elegans
and the major studies done using this worm. C. elegans is a non–hazardous, non–pathogenic and non–parasitic organism. It is small and grows to
about 1 mm in length. It lives in the soil in many parts of the world, where it survives by feeding on microbes such as bacteria. It is of no
economic importance to man. However there has been a great amount of effort invested into the study of this worm which is elaborated in my
thesis. Introduction Roundworms are parasites that can infect people. They usually live in the intestines. There are different kinds of worms that
can cause infection, and they can range in length from 1 millimeter to 1 meter. Most often, eggs, or larvae, live in the soil and get into the body
when you get them on your hands and then touch your mouth. Some can also get into the body through the skin. Like other parasitic ... Show
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elegans has a short life cycle. From egg to egg takes about 3 days, about the same time needed for genetic crosses in yeast. Its life span is around
2 to 3 weeks under suitable living conditions. Compared to the use of other model organisms, such as mice, the short life cycle of C. elegans
reduces the experimental cycle and facilitates biological study. What is unique to this organism is that wild–type individuals contain a constant
959 cells. The position of cells is constant as is the cell number. It is transparent. It is easy to track cells and follow cell lineages. The complete
cell lineage, depicting which cells are derived from which, was completed in the 1980s by John Sulston. This provides a great tool for research
on how genes influence cell fate. These traits enable the study of the biology of a single cell in an intact, living
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69. Why Shouldn T Animal Testing Be Banned?
Today, animal testing is an issue that often occurs throughout the world. There are people who believe animal testing should always be permitted
for research, while others are convinced that these cruel animal examinations should be banned. Opponents argue that animal testing helps gain
knowledge about human diseases, and for testing potential human treatments. Adversary also trusts that Animal testing is beneficial for
furthering pharmaceutical, medical and cosmetic industries. With this in mind, various people argue that animal testing should be authorized due
to beneficial purposes, however; there is evidence explaining as to why the protesters are wrong on many levels.
To begin, people in society believe animal testing should not be banned. There are
many ... Show more content on Helpwriting.net ...
To clarify, Computer models such as, virtual reconstructions of human molecular structures, can predict the toxicity of substances without
invasive experiments on animals. Sophisticated computer models do show the various interactions between cells, tissues, and organs (etc). This
explains why the opponent's opinion is imprecise.
As one can see, animal testing has played a controversial topic throughout the world. Many people overlook the different aspects of animal
testing. There are some who think animal testing is beneficial for our society, while there are others who know animal experimentation is wrong.
Opponents argue that animal testing helps gain knowledge about human diseases, and for testing potential human treatments. But animal
experimentation does not benefit the animals themselves, it harms them. Clearly,
Organs
on
Chips, SenCee Tox, and sophisticated computer models as alternatives to animal testing, are determined more accurate than using
helpless animals as experimentation dummies. Various people argue that animal testing should be authorized due to beneficial purposes. Little
do they know, there is evidence to prove their opinions
are
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71. Wnt/Β-Catenin Signaling Pathway Analysis
Introduction Sea urchin embryos have been studied as model organisms for over 100 years. This organism is a great resource because of its
straightforward artificial spawning, fertilization, and its embryo optical transparency. Also, the sea urchin simple organization makes it great to
study morphogenetic movements and effects (Hardin et al., 1995). The ability of an organism to function normally is dependent on all the cells
of its different organs communicating effectively with their surroundings. This occurs via signal transduction pathways. The Wnt/ß–catenin
signaling pathway is one of these signal transduction pathways that direct two important development events for body plan organization;
animal–vegetal (AV) axis pattering and germ layer specification. ... Show more content on Helpwriting.net ...
In the absence of Wnt, cytoplasmic β–catenin protein is constantly degraded by the action of the Axin complex. β–catenin protein binds to the
Axin complex where is phosphorylated by CK1 and GSK3 and this results in its proteasomal degradation and prevents it from reaching the
nucleus to activate Wnt target gene expression (He et al., 2004). The Wnt/β–Catenin pathway is activated when a Wnt ligand binds to the
receptors Frizzled (Fz) and LRP5/6 (low–density lipoprotein receptor–related protein 5/6) The formation of a likely Wnt–Fz–LRP6 complex,
together with the recruitment of the protein Dishevelled (Dvl), results in β–catenin phosphorylation and stabilization, which then, accumulates
and travels to the nucleus to activates Wnt target gene expression (Figure 1b) (MacDonald et al.,
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73. Zebra Shark Research Paper
Make a Copy: Survival of a Species
The Stegostoma fasciatum (zebra shark) is an endangered species found in Indo–Pacific oceans1. The species has been observed for migratory
behavior and in recent years, for cases of parthenogenesis– a form of asexual reproduction in which the embryos are not fertilized. The species
reproduces sexually in its natural habitat. Cases of parthenogenesis have been observed in captive females, isolated from any males of the same
species or related species. The switch from sexual reproduction to asexual reproduction has been observed in the absence of mates and stressful
environments in several species such as Aetobatus narinari (eagle ray)2. The occurrence of parthenogenesis in captive S. fasciatum is likely a
survival mechanism which ensures the development of future generations for evolutionary purposes. ... Show more content on Helpwriting.net ...
fasciatum in the Burj Al Arab aquarium in Dubai3. At the time, the hatchling was thought to have been the result of hybridization of a
Carcharhinus melanopterus or sperm storage from prior mating. The former had never been recorded and the latter seemed impossible as the
female had been in captivity for six years3. The same female shark had produced eggs in 2006, which curatorial staff had discarded. When the
same female went through another egg cycle in 2007, the decision was made to leave the eggs to test for parthenogenesis3. Tissue samples were
collected from two deceased embryos, each from 2007 and 2008, as well as from the neonate who died 80 days after hatching, to determine
whether the embryos were hybrids or parthenogenetically reproduced. The tests confirmed that the embryos were diploid zygotes with higher
homozygosity than the mother– a result of automictic terminal fusion
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75. This Essay Will Explore The Benefit Of Animals Being Used
This essay will explore the benefit of animals being used in biomedical research, the actions implemented to protect animal welfare as well as
other viable options to minimize harm to animals. Science experiments using animals have created a foundation for advances in biomedical
sciences. Animals used in medical sciences can be traced back to 384–322 BCE in Greek writings of Aristotle followed by Erasistratus, 304–358
BCE (Dey). Some of the most rudimentary knowledge known to man now was found through animal experimentation. Such as the fact that
arteries contain blood which was proven by Galen (130–200 AD) when he revealed the arteries of live animals. Vaccines to protect against
smallpox, a very contagious disease, using cowpox cultures ... Show more content on Helpwriting.net ...
The principle of the 3R's derived from support of the Universities Federation for Animal Welfare for Russell and Burch's Principles of humane
experimental technique (1959) to be published (Bayvel). The 3R's work well in combination with many organizations on–site, nationally and
worldwide that monitor research for best practice. Animal models in experimentation serve in an imperative role. Currently, substances intended
for human use (drugs or devices) must be tested in an animal model first to determine if they must be adjusted, denied or approved. Research
conducted on diseased animals provide insight to progression of similar diseases in humans, improve knowledge of biological responses to
various substances and devices. They also result in the production of various products such as food additives, agrochemicals, vaccines, implants
and pharmaceuticals. It has been estimated that more than 1,200,000 species of animals have been described, but 97% of the animals used for
biomedical purpose belong to only 10 of them. They are rat, mouse, rabbit, chicken, dog, guinea pig, pig, hamster, monkey, and cat(Pal).
Roughly, 95% of studies are conducted in mice (Dey). A different species is used only when it is a more closely matching system to the
equivalent in humans. Many things must be considered when choosing a model for research; availability, anatomic characteristics, stage of life,
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77. Ethanol And Alternative Sources Of Energy
Abstract Due to energy and environmental concerns, producing fuels from renewable energy sources has seen advancements, especially through
collecting biofuels produced from microbes. Many of the biofuels produced from microbes are done so by different pathways in order to
generate fatty acid branched–chain esters (FABCEs) and branched fatty acid branched–chain esters (BFABCEs), which are promising
isopentenols. These can be produced via multiple pathways, the leucine and valine pathway as well as the fatty acid pathway. Another and main
source pathway producing biofuels, which produces isopentyl diphosphate (IPP) and dimethylallyl dipho–sphate (DMAPP), are the 2–methyl–
(D)–erythritol–4–phosphate (MEP) and mevalonate–dependent (MVA) ... Show more content on Helpwriting.net ...
This is proof that it is crucial to begin to create biofuels that have a lesser negative impact that can sustain the energy demands that we have
today. Currently, as seen in the table, microbes have been proven to produce ethanol, biodiesel and hydrogen, which are all sources that can be
used for producing renewable fuels. One of the various types of ethanol produced are C5 alcohols also referred to as isopentenols and other 5
branched carbon alcohols. As Connor and Liao suggest Higher chain alcohols (C3–C5) contain a high energy density, and are compatible with
the current infrastructure as they are less hygroscopic. These alcohols (iso–propanol, 1–propanol, 1–butanol, isobutanol, 3–methyl–1–butanol,
2–methyl–1–butanol, isopentenol) can be blended with gasoline and also have potential to be used as replacements, as 1–butanol has already
been shown to perform well in conventional gasoline engines (Connor; Liao, 2009). There is some controversy about how current biofuels are
not efficient at low temperature; however, FABCEs and BFABCEs have low freezing points, which can allow for the biofuel to have greater
performance (Tao et. al, 2015). As previously mentioned, isopentenols have properties, which mirror those of octane and
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