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Advantages of using amphibians in animal experiments

Basic physiology. The basic physiology of amphibians is relatively well understood.

Amphibian diversity

Favorable phylogenies. Amphibians have phylogenies that are both well understood and

complex, which lend themselves to sophisticated experimental designs shaped by evolutionaryhistory

Wide range of habitats. Amphibians are found in a wide range of habitats and, accordingly, show

a wide range of morphological and physiological adaptations to these habitats

Sufficiently similar to mammals

Why are fruit flies used for genetics experiments?

They have a very short generation time so you can have several generations within days. They also havea high mutation rate and can easily BE mutated so you can look at a lot of different phenotypes veryeasily. Their genetics is well understood and documented too so you have a huge base of knowledge at

your fingertips. Drosophila melanogasteris a popular experimental animal because it is easily cultured inmass out of the wild, has a short generation time, and mutant animals are readily obtainable

Cell determinationDefinitionnounThe process in which a previously undifferentiated cell is already programmed to become a specific cell type byfollowing a specified path towards cell differentiation.

Supplement

Cell determination is influenced by the action of the extracellular environment and the contents of the cell's genome.When a cell is said to be determinedit means that the cell is irreversibly committed to a specific cell fate.

Gel Electrophoresis

Gel electrophoresis is a method for separation and analysis of macromolecules(DNA,RNAandproteins) and their fragments, based on their size and charge

Animal Husbandry

Animal husbandry is theagriculturalpractice ofbreedingand raisinglivestock.

Differential gene expression

cells differentiate through differential gene expression. The three postulates of differential gene

expression are as follows:

1.

Every cell nucleus contains the complete genome established in the fertilized egg. In molecular terms, the

DNAs of all differentiated cells are identical.

2.

http://www.biology-online.org/dictionary/Cell_differentiationhttp://www.biology-online.org/dictionary/Genomehttp://www.biology-online.org/bodict/index.php?title=Cell_fate&action=edithttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Proteinshttp://en.wikipedia.org/wiki/Proteinshttp://en.wikipedia.org/wiki/Proteinshttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Animal_breedinghttp://en.wikipedia.org/wiki/Animal_breedinghttp://en.wikipedia.org/wiki/Animal_breedinghttp://en.wikipedia.org/wiki/Livestockhttp://en.wikipedia.org/wiki/Livestockhttp://en.wikipedia.org/wiki/Livestockhttp://en.wikipedia.org/wiki/Livestockhttp://en.wikipedia.org/wiki/Animal_breedinghttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Proteinshttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/DNAhttp://www.biology-online.org/bodict/index.php?title=Cell_fate&action=edithttp://www.biology-online.org/dictionary/Genomehttp://www.biology-online.org/dictionary/Cell_differentiation

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The unused genes in differentiated cells are not destroyed or mutated, and they retain the potential for being

expressed.

3.

Only a small percentage of the genome is expressed in each cell, and a portion of the RNA synthesized in

the cell is specific for that cell type.

Gene probeA gene probe is a specific segment of single-strand DNA that is complementary to a desired gene.

Read more:http://www.answers.com/topic/what-is-a-gene-probe#ixzz2PBc1NjqJ

Reasons for human cloning

Infertility Curing diseases Genetic illness Replacing body parts

Against

Human rights

Religious beliefs Embryos at risk Killing embryos

Ethical objections to embryonic stem cell research

Killing human beings

The Moral Status of the Embryo According to different moral views, the embryo or fetus has asignificant moral status or a right to life

The 14 Day View The problem with the 14 day view is that it identifies us, what is

fundamentally us, with facts about our body or physical organism. Yet for many people, weare more than physical entities we are minds, or conscious minds to be more precise.

Potentiality Another objection to using cloned cells and embryos is that they are potentialpersons.

using "spare" human embryos for research means a lack of respect for the beginning of humanlife, and in the second--whether creation of embryos for research is morally worse thanexperimentation on already created, but unused human embryos

Ethical objections to therapeutic cloning

Slippery slope to reproductive cloning Although the embryo is produced in an unorthodox way, it still has the right to live

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Alzheimer's disease (AD) is a progressive neurodegenerative disorder which impairs the memory andintellectual abilities of the affected individuals. Loss of episodic as well as semantic memory is an earlyand principal feature. The basal forebrain cholinergic system is the population of neurons most affectedby the neurodegenerative process. Extracellular as well as intracellular deposition of beta-amyloid or

Abeta (Abeta) protein, intracellular formation of neurofibrillary tangles and neuronal loss are theneuropathological hallmarks of AD. In the last few years, hopes were raised that cell replacement therapywould provide cure by compensating the lost neuronal systems. Stem cells obtained from embryonic aswell as adult tissue and grafted into the intact brain of mice or rats were mostly followed by theirincorporation into the host parenchyma and differentiation into functional neural lineages

The Human Fertilisation and Embryology Authority (HFEA) is a statutory body in theUnitedKingdomthat regulates and inspects all UK clinics providingin vitro fertilisation,artificial inseminationandthe storage of humaneggs,spermorembryos. It also regulates Human Embryo research.

Human Fertilisation and Embryology Act 1990

Main article:Human Fertilisation and Embryology Act 1990

The 1990 Act provided for the establishment of the Human Fertilisation and Embryology Authority

(HFEA), an executive, non-departmental public body, the first statutory body of its type in the world. The

HFEA is the independent regulator for IVF treatment and human embryo research and came into effect

on 1 August 1991. The 1990 Act ensured the regulation, through licensing, of:

the creation of human embryos outside the body and their use in treatment and research

the use of donated gametes and embryos

the storage of gametes and embryos

An HFEA research licence is required for any activity involving the use of an embryo for research.

Polygenetic inheritance

'A single characteristic that is controlled by two or more genes' present onmany loci

Each allele of a polygenic character often contributes only a small amount to the over allphenotype. This makes studying the individual alleles difficult.

In addition environmental effects smooth out the genotypic variation to give continuous

distributionPolygenic inheritance can cause a trait to have continuous variation,which means the characteristic does not have discrete forms and instead variesgradually between two extremes. curves.

Epistasis is the masking of the phenotypic effect of either one or both members of a pair ofalleles by agene or genes of a different pair of alleles. So one locus determines the color of the flower: however, theother locus controls whether or not the flower-color locus is masked or expressed.

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Discontinuous variation

This is where individuals fall into a number of distinct classes or categories, and is based on features that

cannot be measured across a complete range. You either have the characteristic or you don'tn. Such

data is called discrete (or categorical) data. Chi-squared statistical calculations work well in this case.

Discontinuous variation is controlled by alleles of a single gene or a small number of genes. The

environment has little effect on this type of variation.

Continuous variation

In continuous variation there is a complete range of measurements from one extreme to the other.

Continuous variation is the combined effect of many genes (known as polygenic inheritance) and is

often significantly affected by environmental influences. Milk yield in cows, for example, is determined

not only by their genetic make-up but is also significantly affected by environmental factors such as

pasture quality and diet, weather, and the comfort of their surroundings. When plotted as a histogram,

these data show a typical bell-shaped normal distribution curve, with the mean (= average), mode (=

biggest value) and median (= central value) all being the same.

Standard Deviation ()

This is a measure of the variability of a data set. Put simply, the taller and narrower the histogram, thelower the SD () and the less variation there is. For a low, wide, histogram, the opposite applies:

Standard Error is a refinement of this, which takes into account sample size (n). The formula is:

Sampling Error

When collecting data, it is vital that the data is reliable and reflects real differences in the

population. This can be ensured by having a large data size, but it is also necessary to ensure that

the data collected is typical of the whole population in other words, that it is randomly

collected. In the laboratory, we repeat experiments 3 times and/or pool class data. In field-work,

we use random number tables; grids laid out with tape-measures, and large numbers of quadrats

to ensure that our data are reliable and randomly collected.

N.B. It is easy to (unwittingly) introduce bias into the collection of results, and to avoid bias is an

important point to make in your answers to questions on this topic

Causes of Variation

Variation in the phenotype is caused either by the environment, by genetics, or by a combination of

the two. Meiosis and sexual reproduction introduces variation (see Ch 1), through Independent

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assortment of the parental chromosomes; through Crossing-over during Prophase I; and through

the random fertilisation that forms the zygote.

Twin studies (studies involving twins) help disentangle the relative importance of environmental

andgeneticinfluences on individual traits and behaviors. Twin research is considered a key tool

inbehavioral geneticsand related fields. Alternative groups that can also be studied based on facts about

genetic similarity include fullsiblingsin general andadoptees.

Twins are a valuable source for observation because theirgenotypesand family environments tend to be

similar. More specifically,monozygotic(MZ) or "identical"twins, share nearly 100% of their

geneticpolymorphisms, which means that most variation in pairs' traits (measured height, susceptibility to

boredom, intelligence, depression, etc.) is due to their unique experiences.Dizygotic(DZ) or "fraternal"

twins share only about 50% of their polymorphisms. Fraternal twins are helpful to study because they

tend to share many aspects of their environment (e.g., uterine environment, parenting style, education,

wealth, culture, community) by virtue of being born in the same time and place.

The classical twin design compares the similarity of indentical (identical) and fraternal (fraternal) twins.

Identical twins are almost always more similar than fraternal twins because of higher genetic similarity

coupled with the same amount of environmental similarity. By comparing many hundreds of families of

twins, researchers can then understand more about the complementary roles of genetic effects, shared

environment, and unique environment in shaping people.

Modern twin studies have shown that almost alltraitsare in part influenced bygeneticdifferences, with

some characteristics showing a strong influence (e.g.height), others an intermediate level

(e.g.intelligence quotient) and some more complexheritabilities, with evidence for different genes

affecting different aspects of the trait as in the case ofautism.

Organ

A group oftissues that perform a specific function or group of functions

System

A group oforgans that work together to carry out a particular task

Stem cells arebiological cellsfound in all multicellularorganisms, that candivide(throughmitosis)anddifferentiateinto diverse specialized cell types and can self-renew to produce more stem cells

The cell cycle, orcell-division cycle, is the series of events that take place in acellleading to itsdivision and duplication (replication)

Crossing over occurs at prophase 1 of meiosis

Metaphase 1 : The random assortment of bivalent takes place.Independent assortment of alleles takes place at anaphase 1

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Weighing Plants: Fresh vs. Dry Weight

Measuring Fresh Weight: While you can technically measure the fresh weight of plants without

harming them, the simple act of removing a plant from its growing "medium" can cause trauma

and affect the ongoing growth rate and thus your experiment. Measuring the fresh weight of

plants is tricky and should probably be saved as a final measure of growth at the end of theexperiment. Here is the process for measuring fresh weight:

1. Remove plants from soil and wash off any loose soil.

2. Blot plants gently with soft paper towel to remove any free surface moisture.

3. Weigh immediately (plants have a high composition of water, so waiting to weigh them

may lead to some drying and therefore produce inaccurate data).

Measuring dry weight: Since plants have a high composition of water and the level of water in a

plant will depend on the amount of water in its environment (which is very difficult to control),

using dry weight as a measure of plant growth tends to be more reliable. You can only capture

this data once as a final measure at the conclusion of your experiment.

1. Remove the plants from the soil and wash off any loose soil.

2. Blot the plants removing any free surface moisture.

3. Dry the plants in an oven set to low heat (100 F) overnight.

4. Let the plants cool in a dry environment (a Ziploc bag will keep moisture out) - in a humid

environment the plant tissue will take up water. Once the plants have cooled weigh them

on a scale.

5. Plants contain mostly water, so make sure you have a scale that goes down to milligrams

since a dry plant will not weight very much.

A chromosome is an organized structure ofDNAandproteinfound incells. It is a single piece of coiledDNA containing manygenes,regulatory elementsand othernucleotide sequences. A structure withinthe cell that bears the genetic material as a threadlike linearstrand ofDNA bonded to various proteins in

the nucleus ofeukaryotic cells, or as a circularstrand ofDNA (orRNA in some viruses) inthe cytoplasm ofprokaryotes and in the mitochondrion and chloroplast of certain eukaryotes.

A hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome anddetermines a particular characteristic in an organism

Functions of histones

Compacting DNA strands

Histones act as spools around which DNA winds. This enables the compaction necessary to fit the

largegenomesof eukaryotes inside cell nuclei: the compacted molecule is 40,000 times shorter than an

unpacked molecule

Remodels chromatinA stud book, also called a breed registry, is a list of all of the known individual animals in a breed.

How to extract stem cells

However, when extracting embryonic stem cells, the blastocyst stage signals when to isolate stem

cells by placing the "inner cell mass" of the blastocyst into a culture dish containing a nutrient-rich

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broth. Lacking the necessary stimulation to differentiate, they begin to divide and replicate while

maintaining their ability to become any cell type in the human body. Eventually, these

undifferentiated cells can be stimulated to create specialized cells.

Stem cell cultures

Human embryonic stem cell colony[Wikipedia]

Stem cells are either extracted from adult tissue or from a dividing zygote in a culture dish. Once

extracted, scientists place the cells in a controlled culture that prohibits them from further

specializing or differentiating but usually allows them to divide and replicate. The process of growing

large numbers of embryonic stem cells has been easier than growing large numbers of adult stem

cells, but progress is being made for both cell types

Stem cell lines

Once stem cells have been allowed to divide and propagate in a controlled culture, the collection of

healthy, dividing, and undifferentiated cells is called a stem cell line. These stem cell lines are

subsequently managed and shared among researchers. Once under control, the stem cells can be

stimulated to specialize as directed by a researcher - a process known as directed differentiation.

Embryonic stem cells are able to differentiate into more cell types than adult stem cells.

Multipotent - the ability to differentiate into a closely related family of cells. Examples includehematopoietic (adult) stem cells that can become red and white blood cells or platelets.

Chimeras

People also take issue with the creation of chimeras. A chimera is an organism that has both humanand animal cells or tissues. Often in stem cell research, human cells are inserted into animals (like

mice or rats) and allowed to develop. This creates the opportunity for researchers to see what

happens when stem cells are implanted. Many people, however, object to the creation of an

organism that is "part human"

Inbreeding isreproductionfrom thematingof parents who are closelyrelated genetically.[1]

Inbreeding

results in increasedhomozygosity, which can increase the chances of offspring being affected

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byrecessiveor deleterious traits.[2]

This generally leads to a decreasedfitnessof apopulation,[3][4]

whichis calledinbreeding depression.

Ex-situ conservation, while helpful in man's efforts to sustain and protect our environment, is rarely

enough to save a species from extinction. It is to be used as a last resort, or as a supplement to in-situ

conservationbecause it cannot recreate the habitat as a whole: the entiregenetic variationof a species,itssymbioticcounterparts, or those elements which, over time, might help a species adapt to its changing

surroundings. Instead, ex-situ conservation removes the species from its natural ecological contexts,

preserving it under semi-isolated conditions whereby natural evolution and adaptation processes are

either temporarily halted or altered by introducing the specimen to an unnatural habitat. In the case

ofcryogenicstorage methods, the preserved specimen's adaptation processes are frozen altogether. The

downside to this is that, when re-released, the species may lack the genetic adaptations and mutations

which would allow it to thrive in its ever-changing natural habitat.

Furthermore, ex-situ conservation techniques are often costly, with cryogenic storage being economically

infeasible in most cases since species stored in this manner cannot provide a profit but instead slowly

drain the financial resources of the government or organization determined to operatethem.Seedbanksare ineffective for certain plantgenerawith recalcitrant seeds that do not remain fertile

for long periods of time. Diseases and pests foreign to the species, to which the species has no natural

defense, may also cripple crops of protected plants in ex-situ plantations and in animals living in ex-situ

breeding grounds. These factors, combined with the specific environmental needs of many species, some

of which are nearly impossible to recreate by man, make ex-situ conservation impossible for a great

number of the world's endangered flora and fauna.

The IUCN Red List of Threatened Species (also known as the IUCN Red List orRed Data List),founded in 1963, is the world's most comprehensive inventory of the global conservationstatusofbiological species. TheInternational Union for Conservation of Nature(IUCN) is the world's mainauthority on the conservation status of species. A series ofRegional Red Listsare produced by countries

or organizations, which assess the risk of extinction to species within a political management unit.

In-situconservation is on-siteconservationor the conservation of genetic resources in naturalpopulations ofplantoranimalspecies, such asforest genetic resourcesin natural populations of treespecies. It is the process of protecting anendangeredplantoranimalspeciesin its naturalhabitat, eitherby protecting or cleaning up the habitat itself, or by defending the species frompredators. It is applied toconservation ofagricultural biodiversityinagroecosystemsby farmers, especially those usingunconventional farming practices. Inagriculture,in situ conservation techniques are an effective way toimprove, maintain, and use traditional or native varieties of agricultural crops. Such methodologies linkthe positive output of scientific research with farmers' experience and field work Wildlife and livestockconservation is mostly based on in situ conservation

The Advantages and Disadvantages of Zoos

1. Animals have been kept in captivity for many years and there are many advantages of zoos.

2. Firstly, in modern zoos animals are placed in enclosures which try to simulate theirnatural habitats. 3. In these enclosures they are protected from their natural predators and

well looked after. 4. The animals are provided with shelter, food and medical

attention. 5. Secondly, zoos provide the public with educational information aboutanimals. 6. They increase the publics knowledge of the dangers many animals face and the

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kind of habitats they live in. 7. Lastly, zoos often rescue animals which would have otherwise

been killed or animals in captivity which have been treated cruelly by humans.

8. On the other hand, there are also some disadvantages of zoos. 9. Campaigners argue that zoos

are cruel for animals and that the enclosures where they are kept are far too small. 10.

They also argue that some animals are taken out of their natural environments. 11. Problems

have arisen for animals that are faced with different climates, especially those from hot countries that

then have to survive cold winters somewhere in Europe for example. 12. Finally, not all zoos

provide their animals with the care and attention they require. 13. In some zoos animals are kept in

dirty cages, are undernourished and not given any medical treatment.

Animal Transfers

Captive breeding and considerations involved

with moving animals

Why is there any need to move animals? Successful captive breeding programmes

will ge e a e su p us d dua s o de o a a ea y popu a o s nerate surplus individuals. In order to maintain

healthy populations withincaptive environments, and to maintain genetic variability within those populations,

animal transfers are essential. It is therefore critical to have both the capability and

the facilities in place for such movements.

Record Keeping

Accurate and organised record keeping is a

fundamental requirement within captive

Legislation

Legislation covers national (including

fundamental requirement within captive most of the EU) and international (non

breeding programmes and for animal transfers

Animals have to be moved when required, for

example if new births mean the collection is

Convention for the International Trade in

Endangered Species of wild fauna and

flora (CITES).

example if new births mean the collection is

over stocked, or if an animal is an important

individual within a captive breeding

programme.

Animal transfers are initiated in a number of

wayg p s. One is through Studbook Keeperrecommendations. The studbooks list all the

individuals within a captive breeding

programme and enable appropriate groupings

of animals to be made.

Another way is through the production of

2

Wanted\Surplus lists which are circulated

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through BIAZA & EAZA (British and Irish, and

European Association of Zoos and Aquaria)

websites. There is also liaison between zoos at

Curatorial and Registrar levels

Summary References / Information

important future within Europe.

www.defra.gov.uk/foodfarm/animaltrade

/imports/iins/livebalai/index.htm

www.defra.gov.uk/animal/welfare

Animal transfers are a vital part of captive

breeding programmes.

Co-operation and good communication is

essential.

Good knowledge of and adherence to

ifi l i l ti i f d t l ( i ll www.cites.org

4

specific legislation is fundamental (especiallyhealth and trade legislation).

The final part of the process is the actual

transport this alone has many potential

issues!

STUDBOOKS

A breed registry, also known as a herdbook, studbook orregister, inanimal husbandryandthehobbyofanimal fancy, is an official list of animals within a specificbreedwhose parents are known.Animals are usually registered by their breeders when they are still young. The terms "studbook" and"register" are also used to refer to lists of male animals "standing at stud", that is, those animals actively

breeding, as opposed to every known specimen of that breed.

Inbreeding depression is the reducedfitnessin a givenpopulationas a result of breeding of relatedindividuals. It is often the result of apopulation bottleneck. In general, the higher the genetic variationwithin a breeding population, the less likely it is to suffer from inbreedingdepression. Inbreedingdepression seems to be present in most groups of organisms, but varies across mating systems.

Glycolysis (from glycose, an older term[1]

for glucose + -lysis degradation) is themetabolic pathwaythat

convertsglucoseC6H12O6, intopyruvate, CH3COCOO

+ H+. Thefree energyreleased in this process is

used to form the high-energy compounds ATP (adenosine triphosphate) and NADH (reduced

nicotinamide adenine dinucleotide).[2]

Education1)Zoos seek to educate the general public through informing visitors about conservationcrises, and inspiring them to care enough to become involved through donations or othermeans. Furthermore, they provide education material on specific animals and habitats, toincrease visitor's knowledge base about animals and their habitats. Ultimately, the idea isthat if people feel a connection or empathy for the animals, they will feel motivated to takegreater efforts toward supporting conservation, through moderating their environmental

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impact, participating in local conservation efforts, and donations to field conservation funds.This is particularly important for children, as they often spear-head family changes--forexample, the recycling movement largely grew through schools developing recyclingprograms, and educating children on the importance of recycling; the kids in turn,encouraged their parents to recycle. Children also represent the next generation of potentialconservationists.

Research1) Zoo populations provide opportunities for many different avenues of research. Inparticular, the genetic research and management of small populations is crucial formaintaining genetic diversity of zoo populations themselves. However, this research is alsohelpful in learning to manage and conserve diversity in wild populations, that are oftenincreasingly fragmented and isolated.

2)They provide observation and sampling opportunities for topics that may not be feasible inthe wild (for example, projects that require close-range observation, or fecal sampling thatmay not be possible in the wild--for example, fecal samples collected from the spider

monkeys at Brookfield Zoo before and after a stressful experience-a vet exam-are essentialto my pilot research).

3)Finally, zoo research is crucial in monitoring the welfare and health of the animalthemselves, and in making modifications to promote welfare.

However, an SEM and TEM also share some differences. The method used

in SEM is based on scattered electrons while TEM is based on transmitted

electrons. The scattered electrons in SEM are classified as backscattered or

secondary electrons. However, there is no other classification of electrons

in TEM.

The scattered electrons in SEM produced the image of the sample after the

microscope collects and counts the scattered electrons. In TEM, electrons

are directly pointed toward the sample. The electrons that pass through the

sample are the parts that are illuminated in the image.

The focus of analysis is also different. SEM focuses on the samples surfaceand its composition. On the other hand, TEM seeks to see what is inside or

beyond the surface. SEM also shows the sample bit by bit while TEM shows

the sample as a whole. SEM also provides a three-dimensional image while

TEM delivers a two-dimensional picture.

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In terms of magnification and resolution, TEM has an advantage compared

to SEM. TEM has up to a 50 million magnification level while SEM only

offers 2 million as a maximum level of magnification. The resolution of

TEM is 0.5 angstroms while SEM has 0.4 nanometers. However, SEMimages have a better depth of field compared to TEM produced images.

Another point of difference is the sample thickness, staining, and

preparations. The sample in TEM is cut thinner in contrast to a SEM

sample. In addition, an SEM sample is stained by an element that

captures the scattered electrons.

In SEM, the sample is prepared on specialized aluminium stubs and placed

on the bottom of the chamber of the instrument. The image of the sample isprojected onto the CRT or television-like screen.

On the other hand, TEM requires the sample to be prepared in a TEM grid

and placed in the middle of the specialized chamber of the microscope. The

image is produced by the microscope via fluorescent screens.

Another feature of SEM is that the area where the sample is placed can be

rotated in different angles.

TEM was developed earlier than SEM. TEM was invented by Max Knoll and

Ernst Ruska in 1931. Meanwhile, SEM was created in 1942. It was

developed at a later time due to the complexity of the machines scanning

process.

Summary:

1.Both SEM and TEM are two types of electron microscopes and are tools to

view and examine small samples. Both instruments use electrons or

electron beams. The images produced in both tools are highly magnified

and offer high resolution.

2.How each microscope works is very different from another. SEM scans

the surface of the sample by releasing electrons and making the electrons

bounce or scatter upon impact. The machine collects the scattered electrons

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and produces an image. The image is visualized on a television-like screen.

On the other hand, TEM processes the sample by directing an electron

beam through the sample. The result is seen using a fluorescent screen.

3.Images are also a point of difference between two tools. SEM images arethree-dimensional and are accurate representations while TEM pictures are

two-dimensional and might require a little bit of interpretation. In terms of

resolution and magnification, TEM gains more advantages compared to

SEM.

Read more: Difference Between TEM and SEM | Difference Between | TEM

vs SEM http://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyK

Differential centrifugation is a common procedure inmicrobiologyandcytologyused to separatecertainorganellesfrom wholecellsfor further analysis of specific parts of cells. In the process,atissuesample is firsthomogenisedto break thecell membranesand mix up the cell contents. Thehomogenate is then subjected to repeatedcentrifugations, each time removing the pellet and increasingthecentrifugal force. Finally, purification may be done throughequilibrium sedimentation, and the desiredlayer is extracted for further analysis. The homogenised sample is now ready for centrifugation inanultracentrifuge. An ultracentrifuge consists of a refrigerated, low-pressure chamber containing a rotorwhich is driven by an electrical motor capable of high speed rotation

Vegetative reproduction (vegetative propagation, vegetative multiplication, vegetative cloning) is aform ofasexual reproductionin plants. It is a process by which new individuals arise without production

ofseedsorspores. It can occur naturally or be induced byhorticulturists.

Although most plants normally reproduce sexually, many have the ability for vegetative propagation, or

can be vegetatively propagated if small pieces are subjected to chemical (hormonal) treatments. This is

becausemeristematic cellscapable ofcellular differentiationare present in many plant tissues.

Horticulturalists are interested in understanding how meristematic cells can be induced to reproduce an

entire plant.

Success rates and difficulty of propagation vary greatly. For examplewillowandcoleuscan be

propagated merely by inserting a stem in water or moist soil. On the other hand,monocotyledons,

unlikedicotyledons, typically lack avascular cambiumand therefore are harder to propagate.

Natural vegetative propagation

Natural vegetative reproduction is mostly aprocessfound inherbaceousandwoodyperennialplants, and

typically involves structural modifications of thestem, although any horizontal, underground part of a plant

(whether stem, leaf, orroot) can contribute to vegetative reproduction of a plant. Most plant species that

survive and significantly expand by vegetative reproduction would be perennial almost by definition, since

http://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://en.wikipedia.org/wiki/Microbiologyhttp://en.wikipedia.org/wiki/Microbiologyhttp://en.wikipedia.org/wiki/Microbiologyhttp://en.wikipedia.org/wiki/Cell_biologyhttp://en.wikipedia.org/wiki/Cell_biologyhttp://en.wikipedia.org/wiki/Cell_biologyhttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Tissue_(biology)http://en.wikipedia.org/wiki/Tissue_(biology)http://en.wikipedia.org/wiki/Tissue_(biology)http://en.wikipedia.org/wiki/Homogenization_(biology)http://en.wikipedia.org/wiki/Homogenization_(biology)http://en.wikipedia.org/wiki/Homogenization_(biology)http://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Centrifugationhttp://en.wikipedia.org/wiki/Centrifugationhttp://en.wikipedia.org/wiki/Centrifugationhttp://en.wikipedia.org/wiki/Centrifugal_force_(fictitious)http://en.wikipedia.org/wiki/Centrifugal_force_(fictitious)http://en.wikipedia.org/wiki/Centrifugal_force_(fictitious)http://en.wikipedia.org/wiki/Equilibrium_sedimentationhttp://en.wikipedia.org/wiki/Equilibrium_sedimentationhttp://en.wikipedia.org/wiki/Equilibrium_sedimentationhttp://en.wikipedia.org/wiki/Ultracentrifugehttp://en.wikipedia.org/wiki/Ultracentrifugehttp://en.wikipedia.org/wiki/Ultracentrifugehttp://en.wikipedia.org/wiki/Asexual_reproductionhttp://en.wikipedia.org/wiki/Asexual_reproductionhttp://en.wikipedia.org/wiki/Asexual_reproductionhttp://en.wikipedia.org/wiki/Seedhttp://en.wikipedia.org/wiki/Seedhttp://en.wikipedia.org/wiki/Seedhttp://en.wikipedia.org/wiki/Sporehttp://en.wikipedia.org/wiki/Sporehttp://en.wikipedia.org/wiki/Sporehttp://en.wikipedia.org/wiki/Horticulturehttp://en.wikipedia.org/wiki/Horticulturehttp://en.wikipedia.org/wiki/Horticulturehttp://en.wikipedia.org/wiki/Meristemhttp://en.wikipedia.org/wiki/Meristemhttp://en.wikipedia.org/wiki/Meristemhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Willowhttp://en.wikipedia.org/wiki/Willowhttp://en.wikipedia.org/wiki/Willowhttp://en.wikipedia.org/wiki/Coleushttp://en.wikipedia.org/wiki/Coleushttp://en.wikipedia.org/wiki/Coleushttp://en.wikipedia.org/wiki/Monocotyledonhttp://en.wikipedia.org/wiki/Monocotyledonhttp://en.wikipedia.org/wiki/Monocotyledonhttp://en.wikipedia.org/wiki/Dicotyledonhttp://en.wikipedia.org/wiki/Dicotyledonhttp://en.wikipedia.org/wiki/Dicotyledonhttp://en.wikipedia.org/wiki/Vascular_cambiumhttp://en.wikipedia.org/wiki/Vascular_cambiumhttp://en.wikipedia.org/wiki/Vascular_cambiumhttp://en.wikipedia.org/wiki/Biological_processhttp://en.wikipedia.org/wiki/Biological_processhttp://en.wikipedia.org/wiki/Biological_processhttp://en.wikipedia.org/wiki/Herbaceous_planthttp://en.wikipedia.org/wiki/Herbaceous_planthttp://en.wikipedia.org/wiki/Herbaceous_planthttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Perennial_planthttp://en.wikipedia.org/wiki/Perennial_planthttp://en.wikipedia.org/wiki/Perennial_planthttp://en.wikipedia.org/wiki/Plant_stemhttp://en.wikipedia.org/wiki/Plant_stemhttp://en.wikipedia.org/wiki/Plant_stemhttp://en.wikipedia.org/wiki/Roothttp://en.wikipedia.org/wiki/Roothttp://en.wikipedia.org/wiki/Roothttp://en.wikipedia.org/wiki/Roothttp://en.wikipedia.org/wiki/Plant_stemhttp://en.wikipedia.org/wiki/Perennial_planthttp://en.wikipedia.org/wiki/Woodhttp://en.wikipedia.org/wiki/Herbaceous_planthttp://en.wikipedia.org/wiki/Biological_processhttp://en.wikipedia.org/wiki/Vascular_cambiumhttp://en.wikipedia.org/wiki/Dicotyledonhttp://en.wikipedia.org/wiki/Monocotyledonhttp://en.wikipedia.org/wiki/Coleushttp://en.wikipedia.org/wiki/Willowhttp://en.wikipedia.org/wiki/Cellular_differentiationhttp://en.wikipedia.org/wiki/Meristemhttp://en.wikipedia.org/wiki/Horticulturehttp://en.wikipedia.org/wiki/Sporehttp://en.wikipedia.org/wiki/Seedhttp://en.wikipedia.org/wiki/Asexual_reproductionhttp://en.wikipedia.org/wiki/Ultracentrifugehttp://en.wikipedia.org/wiki/Equilibrium_sedimentationhttp://en.wikipedia.org/wiki/Centrifugal_force_(fictitious)http://en.wikipedia.org/wiki/Centrifugationhttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Homogenization_(biology)http://en.wikipedia.org/wiki/Tissue_(biology)http://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Organellehttp://en.wikipedia.org/wiki/Cell_biologyhttp://en.wikipedia.org/wiki/Microbiologyhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyKhttp://www.differencebetween.net/science/difference-between-tem-and-sem/#ixzz2Phc3KhyK

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specialized organs of vegetative reproduction, like seeds of annuals, serve to survive seasonallyharsh

conditions. A plant that persists in a location through vegetative reproduction of individuals over a long

period of time constitutes aclonal colony.

In a sense, this process is not one of "reproduction" but one of survival and expansion of biomass of the

individual. When an individualorganismincreases in size via cell multiplication and remains intact, the

process is called "vegetative growth". However, in vegetative reproduction, the new plants that result are

new individuals in almost every respect except genetic. Of considerable interest is how this process

appears to reset theaging clock.[3]

[edit]Artificial vegetative propagation

Vegetative propagation of particularcultivarsthat have desirable characteristics is very common practice.

Reasons for preferring vegetative rather than sexual means of reproduction vary, but commonly include

greater ease and speed of propagation of certain plants, such as many perennial root crops and vines.

Another major attraction is that the resulting plant amounts to a clone of the parent plant and accordingly

is of a more predictable quality than most seedlings. However, as can be seen in many variegatedplants,

this does not always apply, because many plants actually arechimerasand cuttings might reflect the

attributes of only one or some of the parent cell lines. Man-made methods of vegetative reproduction are

usually enhancements of natural processes, but they range from rooting cuttings tograftingand artificial

propagation by laboratorytissue culture.

perennating organ

In plants, that part of abiennial plantor herbaceous perennial that allows it to survive the

winter; usually a root, tuber, rhizome, bulb, or corm.

Largest:

CytoplasmCell membrane/wallNucleusEndoplasmatic reticulumGolgi aparatusChloroplastMitochondriaVacuoleLysosomeCentrioleMicrotubules/MicrofilamentsRibosome

http://en.wikipedia.org/wiki/Seasonhttp://en.wikipedia.org/wiki/Seasonhttp://en.wikipedia.org/wiki/Seasonhttp://en.wikipedia.org/wiki/Clonal_colonyhttp://en.wikipedia.org/wiki/Clonal_colonyhttp://en.wikipedia.org/wiki/Clonal_colonyhttp://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Plant_senescencehttp://en.wikipedia.org/wiki/Plant_senescencehttp://en.wikipedia.org/wiki/Vegetative_reproduction#cite_note-3http://en.wikipedia.org/wiki/Vegetative_reproduction#cite_note-3http://en.wikipedia.org/wiki/Vegetative_reproduction#cite_note-3http://en.wikipedia.org/w/index.php?title=Vegetative_reproduction&action=edit&section=4http://en.wikipedia.org/w/index.php?title=Vegetative_reproduction&action=edit&section=4http://en.wikipedia.org/w/index.php?title=Vegetative_reproduction&action=edit&section=4http://en.wikipedia.org/wiki/Cultivarhttp://en.wikipedia.org/wiki/Cultivarhttp://en.wikipedia.org/wiki/Cultivarhttp://en.wikipedia.org/wiki/Variegationhttp://en.wikipedia.org/wiki/Variegationhttp://en.wikipedia.org/wiki/Variegationhttp://en.wikipedia.org/wiki/Chimera_(genetics)http://en.wikipedia.org/wiki/Chimera_(genetics)http://en.wikipedia.org/wiki/Chimera_(genetics)http://en.wikipedia.org/wiki/Graftinghttp://en.wikipedia.org/wiki/Graftinghttp://en.wikipedia.org/wiki/Graftinghttp://en.wikipedia.org/wiki/Plant_tissue_culturehttp://en.wikipedia.org/wiki/Plant_tissue_culturehttp://en.wikipedia.org/wiki/Plant_tissue_culturehttp://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006904.htmlhttp://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006904.htmlhttp://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006904.htmlhttp://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006904.htmlhttp://en.wikipedia.org/wiki/Plant_tissue_culturehttp://en.wikipedia.org/wiki/Graftinghttp://en.wikipedia.org/wiki/Chimera_(genetics)http://en.wikipedia.org/wiki/Variegationhttp://en.wikipedia.org/wiki/Cultivarhttp://en.wikipedia.org/w/index.php?title=Vegetative_reproduction&action=edit&section=4http://en.wikipedia.org/wiki/Vegetative_reproduction#cite_note-3http://en.wikipedia.org/wiki/Plant_senescencehttp://en.wikipedia.org/wiki/Organismhttp://en.wikipedia.org/wiki/Clonal_colonyhttp://en.wikipedia.org/wiki/Season

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Under this is cytokinesis differences not mitosis. we are studying this now so i should know.

plant cells:

1.no centrioles

2. form a cell plate at which a new cell wall forms

3. in telophase, phragmoplast (actin myosin microtubules a.k.a. cell plate) forms in center of cell

4. have a cell wall

5. nuclear and cell division found in special regions called meristems

animal cells:

1. centrioles

2. form a cleavage furrow during cytokinesis

3. contractile ring forms approximately midway between the 2 nuclei of the dividing cell

4. no cell wall

5. cells divide everywhere, all the time

In plants

Thespindle fibres are formed by the centrosomes not the cenrioles.The centrioles come to the MTCs (micro tubules organising centers) which are present in the centrosomes which make up the spindle fiberson which the chromosomes are held.

Centromere- The strongest and thinnest region of a chromosome, to which the spindle fiber is attachedduring mitosis. the centromere is the point on the chromosome at which chromatids are held together andto which the spindle fibers attach during cell division. the centromere is visible during cell division as aconstriction along the length of a contracted chromosome.

Do the centrioles disappear during the telophase of mitosis?

On the handout my teacher gave, it said that the centrioles disappear during the

telophase of mitosis along with the spindle fibers. In my book, however, it only

mentions the spindle fibers disappearing, and the picture of the centrioles are stillthere on the diagram of telophase. Thank you in advance.

The spindle fibers do indeed disappear as microtubules depolymerize, but thecentrioles,

as microtubule organizing centers, do not disappear. Indeed, as cytokinesis is completed late in

telophase, each daughter cell contains one of the centrioles that participated in the mitotic division just

completed. During interphase centriole replication occurs. Specifically, at a certain point in G1, the two

centrioles of each pair, which lie at right angles to one another, separate by a few micrometers. During S

phase, a daughter centriole begins to grow near the base of each mother centriole and at a right angle to

it. The elongation of the daughter centriole is usually completed by G2. The two centriole pairs thus

created remain close together in a single centrosomal complex until the beginning of M phase when the

complex splits in two and the two halves begin to separate. Each centrosome now nucleates its own

radial array of microtubules called an aster. The two asters, which initially lie side by side and close to the

nuclear envelope, move apart. By late prophase, the microtubules that interact between the two asters

preferentially elongate as the two asters move apart along the outside of the nucleus. In this way a bipolarmitotic spindle is rapidly formed. Subsequently, the breakdown of the nuclear envelope enables spindle

microtubules to interact with the chromosomes. Trust me, the centrioles NEVER disappear!

Apoptosis (pron.:/ptoss/also pron.:/epptoss/)[2][3]

is the process ofprogrammed cell

death(PCD) that may occur inmulticellular organisms.[4]

Biochemicalevents lead to characteristic cell

changes (morphology) and death. These changes includeblebbing, cell

shrinkage,nuclearfragmentation,chromatin condensation, andchromosomalDNAfragmentation. (See

alsoapoptotic DNA fragmentation.)

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1. Tail / flagellum;

{To swim / to propel it} to the {egg / ovum / vitelline membrane};

2. Small(er) size;

Makes it easier for it to swim / to aid mobility / makes it possible

to produce them in large numbers;3. Haploid number of chromosomes / only one of each chromosome

/ (only) 23 chromosomes rather than 46;

So {normal / diploid} number restored at fertilisation;

4. Acrosome / sac of enzymes; To digest way (in)to egg;

5. Mitochondria; Energy for swimming / eq;

Why large numbers of sperms are produced?

(Produces) {biological / genetic} variation;

No two sperms the same;

Many sperms do not reach egg / increases chances offertilising eggs;Selection for {fittest / eq} sperm;Some sperms defective; 2

Markingpoint

Prokaryotic cell Eukaryotic cell

1 Smaller Larger ;

2 Do not have a nucleus / nucleolus/ have a nucleoid

Have a nucleus / nuclear envelope /nucleolus (allow description) / nonucleoid ;

3 Do not have membrane-bound

organelles / absence of namedorganelle

Have membrane-bound organelles /

presence of named membrane-boundorganelle ;

-

4 Smaller / 70S ribosomes Larger / 80S ribosomes ;

5 Mesosomes / description of

infoldings

No mesosomes ;

6 Circular DNA Linear DNA ;

-

7 No histones / chromosomes Histones / chromosomes ;

8 Murein / mucopeptide /peptidoglycan cell walls / no

cellulose

Cellulose cell walls (if present) ;

9 Flagellum with no microtubules /

eq / reference to basal structure

Flagellum with microtubules / 9+2

arrangement / reference to basalstructure ;

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Explain how the acrosin is released from the acrosome

idea of stimulus e.g. Receptors contact with zona pellucid

acrosome swells

vesicle/acrosome fuses

with sperm cell surface membrane/ exocytosis

Explain the importance of packaging different parts of eukaryotic cells into organelles

Enables different functions to be carried out in different areas. The organelles have theirown compartment,

What arguments might be presented for and against keeping animals in captivity in zoos?

For: role in academic research. Captive breeding with careful use of studbooks to maintain genetic

diversity: reintroduction programs: education

Against: isoloation of animals from family groups. Limted area for living.

Alternatives: Provide species with the safe and most naturalistic environment. Some foundations belives

wildlife belongs in the wild, they conserve species in their natural habitat

Some welfare of animals in zoo is poor as they exhibit stereotypic behaviours such as repetive pacing up

and down and chewing bars. Keeping animals in captivity can, and does, cause immense mental

suffering to the species put on display for our pleasure.

Zoochosis is the term used to describe the stereotypical behaviour of animals in captivity.Stereotypic behaviour is defined as a repetitive, invariant behaviour pattern with no obvious goal orfunction. Stereotypic behaviour is not seen in animals in the wild and is understood to be abnormal and istherefore a negative factor in conservation captive breeding.

Examples of this can be seen at most zoos in such behaviours as:-

Bar Biting, Neck Twisting, Tongue Playing, Excessive Grooming Head Bobbing, Coprophagia, Swaying/Pacing/Circling Excessive Grooming, Vomiting, Self Mutilation

In a2001 studyof 257 captive Giraffe and Okapi in 49 US institutions, it was found that 80% exhibitedsome form of stereotypic behavior.

And the Causes?

Separation from natural habitat Loss of life in normal social groups

Enforced idleness Drugs and medical fertility control

http://dx.doi.org/10.1016/S0168-1591(01)00137-Xhttp://dx.doi.org/10.1016/S0168-1591(01)00137-Xhttp://dx.doi.org/10.1016/S0168-1591(01)00137-Xhttp://dx.doi.org/10.1016/S0168-1591(01)00137-X

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Direct control by humans Caging - a totally alien environment

They believe animals should be bred in protected habitats in the wild

Animals are exhibited on the basis of their crown pulling power rather than on their endangered status.Animals are kept in inappropriate conditions both in terms of physical, mental and social being. Capture

of animal for exhibition may deplete wild populations

Reintroduction of species to the wild cannot be guaranteed.

Peripheral arteries are thearteries(specificallyarteriolesandcapillaries) which are farthest fromtheheart(mouth,hands, and feet).

Features of a good study salters pg 23

Intrinsic rhythm is therateat which theheartbeats with no interference from theCentral NervousSystem.Cellsofcardiac muscle, when left to themselves, will beat atvariablerates. The heart has

twostructures, theSinus nodeand theAtrial ventricular nodethat even out the rate of all thecardiactissue. The rate provided by these two structures is around 100bpm.

The fact that our hearts usually beat at around 60-80 bpm is due to the influence oftheparasympathetic nervous system, specifically theVagus Nerve, which innervated the heart andconstantly sends messages to slow down the rythm. Thesympathetic, oradrenergicnervous system,also innervated the heart and can push the rate up way past the normal rate of 100 bpm.

Genetic counseling

Interpretation of family and medical histories to assess the chance of disease occurrence or

recurrence.

Education about inheritance, testing, management, prevention, resources

Counseling to promote informed choices and adaptation to the risk or condition.

Evidence for the fluid mosaic model salters pg 66-68

Gated channel

channel through a membrane that can be opened or closed by chemical orelectrical events.

The Human Genome Project (HGP) is an internationalscientific researchproject with a primary goal ofdetermining the sequence of chemical base pairs which make up DNA, and of identifying and mappingthe approximately 20,00025,000genesof thehuman genomefrom both a physical and functional

standpoint.[1]

CF is most common amongCaucasians; 4% of people of European descentcarriesoneallelefor CF.

Locus: A parituclar position on a chromosomeHomologous chromosomes: Homologous chromosomes are chromosome pairs, one from each parent,that are similar in length, gene position andcentromerelocation.

Dominant allele: The allele that comes into expression in the phenotype even it was present singleHeterzogous: If the wo alleles coding for a characteristic are differentCarrier:A heterozygous individual bearing an unexpressed defective gene.

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People living with cystic fibrosis face a lifelong challenge of paying for medications, nutrition

supplements, respiratory equipment, physician services, and various other medical expenses. Even

with health insurance to cover some of the costs, the expenses of treatment can be devastating to any

family's budget. If you find the cost of treatment is giving your wallet a squeeze, there are places you

can turn to for help.

Health Insurance

Health insurance coverage is an absolute must-have for people with cystic fibrosis. If you are having

problems getting insurance elsewhere, government programs are available that may be able to help if

you meet eligibility requirements.

Ethical and social issues relating to use of PGID

Who has right to decide if tests should be performed

Implications of medical cost / embryo has rights / disagreement over next step

Issues relating to confidentiality of parents child

Idea that some other abnormality might be found / paternal DNA doesnt match / other family

members have the right to know

False negative

Possible problems in future e.g.: future employment / insurance

Reasons for regulating authorities for human embroyos

Gives guiding on what can be done and what cannot

Idea of setting ethical legal aspects

Judging what is acceptable / follow a code of practices

To ensure the source of embryo is proper and acceptable eg: spare embryo from ivf clinics

To decide the maximum age of the embryo that it could be used

Follow ethical framework

Stopping cloning of humans

Unessacary repeating of resource

To discuss the ethical issues associated with the use of stem cells and make decisions

People involved in embryo research

Able to understand the science and recognize what is possible, benefits and risks. Judge in an

informed manner.

People not involved in embryo research

Ehist

Provides the view of the society. Balanced alternative view

Present the view of those who may object to embryo research, present reasons against their use

eg. Religious reasons

http://cysticfibrosis.about.com/od/resourcesandsupport/a/healthinsurance.htmhttp://cysticfibrosis.about.com/od/resourcesandsupport/a/healthinsurance.htmhttp://cysticfibrosis.about.com/od/resourcesandsupport/a/healthinsurance.htm