91602, 91607 Extinct Species PDF

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AS 91602 (v2) Credits: 3 and/or AS91607 (v2) Credits: 3 Should we bring back an extinct NZ species?

Integrate biological knowledge to develop an informed response to a socio-scientific issue Demonstrate understanding of human manipulations of genetic transfer and its biological implications STUDENT NAME:

Kristina Baird

20/2/19

‘By stating my name above I acknowledge that my entry for AS91602, AND/OR 91607 is my own work, and any external contributions are acknowledged within the assessment.’

Declaration:

Achievement

Integrate biological knowledge to

91602 develop an informed response to a socio-scientific issue.

91607

DATE

Demonstrate understanding of human manipulations of genetic transfer and its biological implications.

Achievement with Merit

Achievement with excellence

Integrate biological knowledge to develop Integrate biological knowledge to develop a a reasoned informed response to a comprehensive informed response to a socioscientific issue. socio-scientific issue. Demonstrate in-depth understanding of human manipulations of genetic transfer and its biological implications.

Demonstrate comprehensive understanding of human manipulations of genetic transfer and its biological implications.

91602 Integrate biological knowledge to develop an informed response to a socio-scientific issue Mark Rubric

Integrates relevant biological knowledge to explain the biological concepts relating to the issue

A 

One biological and one social implication (economic, cultural or environmental) of the issue is explained

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Two different opinions or viewpoints about the issue (one for and one against) from named individuals, groups or organisations explained A personal position and one proposed personal or societal action is explained

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The personal position and proposed personal/societal action are explained by giving reasons, with supporting evidence, on why these have been chosen. An analysis and evaluation of the biological knowledge related to the issue is used to justify a personal position and proposed personal/societal action by one of:

Requirements

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● comparing the significance of the biological and/or social implications ● considering the likely effectiveness of the proposed personal/societal action ● commenting on the sources of biological knowledge used by considering ideas such as validity (date/currency, peer review status, scientific acceptance) or bias (attitudes, values, beliefs).

MARKERS GRADE:

NOT ACHIEVED

ACHIEVED

MERIT

EXCELLENCE

NOT ACHIEVED

ACHIEVED

MERIT

EXCELLENCE

MARKERS COMMENT: MODERATORS GRADE: MODERATORS COMMENT:

Biology 91607: Demonstrate understanding of human manipulations of genetic transfer and its biological implications A

M

E

Describes one manipulation for each of two genetic manipulations

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Describes two biological implications for each of the two genetic manipulations

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Explains two implications within or between the two genetic manipulations.

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Requirements

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This could include the positive and negatives of using microbes, issues with mutation, maintaining the culture of the microbes or any other impact on the health and survival of individuals. Uses biological ideas to explain how or why genetic transfer is manipulated for each of the two genetic manipulations Links biological ideas of genetic manipulation and two biological implications within or between the two. This may involve: justifying, relating, evaluating, comparing and contrasting, analysing. ●

This could include the difficulties in turning on cloning or using CRISPR to bring back an extinct species, the long term effects of genetic manipulation on the individual or any other impact on the health and survival of individuals.

MARKERS GRADE:

NOT ACHIEVED

ACHIEVED

MERIT

EXCELLENCE

NOT ACHIEVED

ACHIEVED

MERIT

EXCELLENCE

MARKERS COMMENT: MODERATORS GRADE: MODERATORS COMMENT:

Should We Bring Back the New Zealand Haast’s Eagle:   xtinction occurs for one or multiple of three reasons:  Extinction is  defined  by  ‘the  dying  out  or  extermination  of  a  species.’ E environmental forces including natural disasters, global change, or habitat loss, or human impact such as the over use of a  species for human use, or thirdly, because of the evolutionary changes occuring in a species, for example poor reproduction,  inbreeding or  a decrease  in  the  total  population.  De-extinction  or resurrection  biology is defined as ‘the process of resurrection   he process of de-extinction involves genetics, selective breeding and reproductive  species that have died out, or gone extinct.’ T cloning technologies. (Encyclopaedia Britannica: Extinction, 5/2/2019)  The  Haast’s  Eagle  (harpagornis  Moorei)  was both the  largest  known predator  to New Zealand’s  prehistoric fauna as well as being the biggest and most dangerous eagle in the world. Maori legends  describe the Haast’s Eagle has a ‘man eating bird’ k nown as Pouakai. It is estimated that the Haast’s  Eagle went extinct relatively recently. Evidence shows that it existed when the Maori first arrived in  New Zealand just over 800 years ago and possibly even when Pakeha settlers arrived in the early  1800’s. Due to the increase in Maori and  Pakeha settlers in New Zealand and the species inability to  adapt to change, the Haast’s Eagle became extinct. Like other large carnivore predators the Haast’s  Eagle food requirements meant that they hunted over a large area. As a result of this, the birds  would of had a decreased population size. Due to the decrease in Moa population because of Maori  hunting, the Haast  Eagles  main  food  source  decreased  and also aided in the extinction of the Haast’s  Eagle. These attributes as well as the clearing of bush and reduced amount of available prey made  the Eagle prone to a loss in population size and eventually extinction. Bringing back the Haast’s  Eagle would  be  problematic  due  to  its  predatory  nature  and size. Therefore, i disagree with the idea of using biotechnology to  bring back  this  species.  Included  in  this  report, I will also be discussing the biotechnological manipulations that provide an  opportunity for how we might bring back extinct species, as well asa the  socio-scientific implications in the idea of bringing  back the Haast’s Eagle. This will include the economic, ethical, cultural, and environmental implications involved in using  biotechnology to de-extinct organisms. (NZ Birds of Prey: Haast’s Eagle: ND) My two focus questions for this report are as  followed:  Biotechnology: Through biotechnology what would the process be for bringing back the Haast Eagle?  Socio-scientific: What would the consequences (advantages/disadvantages) of bringing back the Haast Eagle? Through biotechnology what would the process be for bringing back the Haast Eagle?  There are different ways proposed of bring back extinct species. The two biotechnological manipulations I will be discussing are reproductive cloning and genome editing.  Reproductive Cloning:  Britannica defines cloning as ‘the process of generating a genetically identical copy of a cell or an organism.’C  loning is common  in nature with species that reproduce asexually without  any  genetic  alterations.  Reproductive  cloning  is  the  process  of  creating an animal that is genetically identical  to a relative donor organism through somatic cell nuclear transfer (SCNT.) The  newly created embryo is inserted back into the womb/egg of  the  donor  animal  where  it  can  then develop and be carried until  full term. One example of reproductive cloning through SCNT is Dolly the sheep, which was the first mammal cloned from  SCNT. (Britannica, 2019)  Somatic Cell Nuclear Transfer:

During  Somatic  Cell  Nuclear  Transfer,  scientists remove  a  somatic  cell (for  example  a  skin  cell) from  the organism  they wish to clone. They then extract the nucleus from the  somatic cell and transfer  it  into an egg cell, or oocyte from  a surrogate mother (a closely related  speciesto the chosen  organism) that has also had its nucleus removed while the 

rest of the oocyte is discarded. There are two ways in which scientists can transfer the DNA from the somatic cell into the  enucleated egg cell. During the first  method, the nucleus of  the somatic cell is removed via the use of a needle and then  injected into  the  egg  cell.  During  this  method,  the  newly  manipulated  egg cell is then developed into an embryo in a test tube  before being injected back into the surrogate mother. Once injected back into the surrogate mother’s womb, the nucleus of  the cell is then reprogrammed by the eggs cytoplasmic factors such as proteins and mRNAs that function during the early  development to become a zygote (fertilized egg) nucleus. Ultimately the egg cell is carried until full term where the created  organism which as an identical genetic make up as the organism with the donated somatic cell. (Somatic Cell Nuclear Transfer: Embryology 26/3/2019) (Learn.Genetics: Click and Clone NA)  Advantages/disadvantages of SCNT:  There are some disadvantages involved in the use of SCNT to re introduce an extinct species back into the world. One of  these disadvantages.  Studies have also discovered a high  risk  of  disease  transmission  in techniques such as SCNT where procedures are carried out  outside of a living organism. This is known as in vitro, where “experiments in cellular biology are conducted outside of organisms  or cells.” ( The Marshall Protocol Knowledge Base: ND) Diseases such as BVDV (Bovine viral diarrhea virus) which is a bovine  pathogen which causes reproductive  disorders  and  respiratory  diseases,  which  are  common  in  cloned  cattle.  A  second  disadvantage which results from in vitro experiments is that researches are unable to correctly replicate  the  cellular  conditions unique to the organism. For example, by removing the newly fertilised egg from the host mother and growing the  embryo in  a microbiological  culture,  the  conditions  will  not reflect the conditions of those in a Haast Eagle. (The EFSA Journal:  2009) In relation to using Somatic Cell Nuclear Transfer to de-extent the Haast Eagle, reproductive cloning through the  use of  Somatic Cell  Nuclear  Transfer would not work due to the fact that the related species is not large enough to carry a Haast's  eagles egg. The Haast eagle is believed to of migrated from Australia as the Little Eagle and the Booster Eagle. Due to many  factors the the species evolved over time from a size of roughly 40-55 cm in length to being recognized as the largest eagle  to ever exist.  Due to this  fact, the  use  of  Somatic  Cell  Nuclear  Transfer would not work in cloning the Haast Eagle as it would  not be physically possible for either the Little Eagle or Booster Eagle to carry a Haast Eagle. (Live Science: Tiny Eagle Evolved into Huge Beast that Barely Flew NA)  There are also advantages involved with reproductive cloning through the  process of SCNT such as the curing of diseases and having the ability to  breed  ideal  livestock.  However,  in  relation  to  using SCNT  to  revive  the  Haast Eagle, the disadvantages outway  the  benefits.  Therefore  I  believe  that because the risks involved in reproductive cloning, that we should not  use this technique  to bring  back  the  Haast  Eagle  from extinction. (EFSA  Journal: 2009)  Genome Editing:  Genome  editing  (or  also  known  as  gene  editing)  is  a  series  of  biotechnology  that  allows  scientists  the  ability  to  alter  an  organism’s  D.N.A.  These techniques allow genetic material  to be added, removed, or  altered at  particular  locations on the target de-extinct D.N.A. (U.S. National  Library of Medicine: August 2017)  CRISPR/Cas9:  CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats) is  a  gene-editing  tool  used  in  genome  editing  in  organisms.  It  involves  using  a  guide  R.N.A.  to  match  a  desired  target  gene, and CRISPR/Cas9  which  is  an  endonuclease  (enzyme  which  specialises  in  separating  nucleotides) which then allows the double stranded D.N.A. to split to allow  modifications to occur. (Encyclopedia Britannica: Gene Editing: 21/12/18) 

The CRISPR/Cas9 process consists of two molecules to create a mutation within a DNA sequence. This involves deleting  and/or  adding  the  base  sequence  to  obtain  the  desired  sequence.  The  first  key  molecule  involved  in  the  process  of  CRISPR/Cas9 is the enzyme Cas9 that acts as scissors to cut the double stranded DNA at specific locations in the genome to  allow for sections of the DNA to then be added or removed. The second key molecule is the guide RNA. In the diagram above,  the CRISPR ‘spacer’ sequences are first transcribed into short RNA sequences (otherwise known as crRNAs or CRISPR RNAs)  These newly created RNA sequences are used to guide the system to matching sequences of DNA. Above in the diagram, the  target DNA, once found, Cas9 is able to bind itself to the DNA sequence and cuts it, thus turning off the targeted gene.  The guide RNA is created to find and attach itself to a specific DNA sequence. The RNA bases are complementary to those of  the target DNA sequence in the genome. This makes  sure  that  the  guide RNA  will only bind to the desired target sequence of  DNA and no other regions  of the genome. The Cas9 enzyme follows the guide RNA to the same location on the genome and  makes a cut across both strands of the DNA. Once the DNA has been cut, the cell recognises that there has been damage to  the DNA  and  attempts  to repair it. Scientists can then use techniques such as DNA repair machinery to introduce changes to  one or multiple genes in the genome. (The Wall Street Journal: Meet the Scientists Bringing Extinct Species Back From the  Dead, 11/10/2018)  In relation to using CRISPR/Cas9 in the resurrection of the Haast Eagle, the process would be similar to the de extinction of  the passenger pigeon. Similar to them, the  DNA  of  the  Haast  Eagle  is  not  fully  in tact  and is fragmented due to the age of the  bird and thus does not overlap perfectly causing many mismatches in the base pairings on the genome. These are referred to  as false mutation. With this  in  mind,  scientists would need to  consider using  the  “Little  Eagle”  genome  in  order  to  properly  map the Haast Eagles DNA. This is possible because of the two  birds  are  related  and  share  similar  DNA  sequences.  This  will  allow  scientists  to  find  where  DNA  fragments  overlap despite  the mismatched base pairs. We can then find enough fragments  to gain  a  “depth coverage”  where  we can  thenhave many DNA  fragments  that align  in the  same  region  of  the  genome.  In  relation  to  a  Haast  Eagle, we would need to process and find  overlaps in both the remaining Haast Eagle DNA and its relative  the Little Eagle. In order to edit the genome of the Little Eagle,  we can use a method that involves primordial germ cells (PGC)  - a cell that  will become a sex cell. During this  process,  the  embryo PGC’s are removed from the Little Eagle and allowed to  grow  in  a  controlled  environment  with  the  right  nutrients.  During this part, scientists will then be able to make alterations  to sections of the genome. These alterations are done through  the use of CRISPR/Cas9. Scientists will have the ability to inject  the Cas9 enzyme into the developing embryo of the LittleEagle  to  attach  to  the  desired  genome  and  cut  at  the  target  sites  across the DNA. The newly restored DNA from the Haast Eagle  can now be added to the host birds genome. Here the DNA will  begin  to  repair  the cut through a process of homologous  recombination.  Once complete,  the Little Eagle will now have  its DNA overwritten with the Haast Eagles DNA. Thus resulting  in  a  mix  of  the  two  organisms.  (Revive  and  Restore:  De  Extinction in Detail, N.D)    Advantages/disadvantages of genome editing for de-extinction:  One general disadvantage of using genome editing for the de-extinction is the loss of genetic diversity. Genetic diversity is  defined as the total number of genetic characteristics within the genetic makeup of a species. This is what keeps an entire  species from being wiped out by a singular virus if none of them have natural immunities. Having a lack of genetic diversity  within a newly  re  introduced  species like the  Haast Eagle  would  also  result  in  the lack of mutations that occur. A species will  adapt and change in  result  to their environment, however, if genetic diversity is lost due to the excessive cloning of a species,  then there are no mutations to allow the  newly cloned group to  survive  a  sudden  change  in  environment  or  a newly  introduced disease. (wiseGEEK: N.D.) 

A second disadvantage to using genome editing for the de-extinction of the Haast Eagle is the fact that the revived species  will be a combination of both the Haast Eagle and Little Eagles genetic material. By adding the Haast Eagles harvested DNA  to that of the Little Eagles, the resulting organism would have both the characteristics common to the Haast Eagle as well as  the Little  Eagle.  This  is  a disadvantage as scientists ...