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    (Original post by Mjwilson1988)
    Beads with the same mass as the woodlice.

    thank you guys is this for making sure pressure has no effect on the experiment ? aLso,, what cause the pressure, is it the organoism?


    (Original post by Lujain Al Omari)
    I'd choose glass beads, because there WOULD be something. And to make it a convincing control, use glass beads of the same number and size
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    (Original post by Hannnnah)
    The amount of effort and revision i have put into this exam better pay off!
    I feel the same way - I dislike how half of it is just luck of the paper though. ):
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    (Original post by bubblegummer)
    Also i'm wondering is anyone here taking Chem 5 on wednesday? :confused:
    Yeah I am edexcel unit 5. Soo hard revising for both exams
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    (Original post by MY.)
    For naked mole rat do we need to know how blood clots form ?


    Posted from TSR Mobile
    They may bring it up so its worth going over it.
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    (Original post by bubblegummer)
    Guys, how do you describe the production of genetically modified organisms (for plants, animals and microorganisms) by the use of drugs? could you please explain it to me. thanks in advance


    Also i'm wondering is anyone here taking Chem 5 on wednesday? :confused:
    I'm taking Chem 5 on Wednesday, that one isn't as frightening as Bio 5 though!

    Also, in reply to your question, did you mean the production of Drugs by using GMOs (Plants, Microorganisms and Animals)?

    Microorganisms -

    First isolate a healthy gene which codes for the protein (drug) you wish to make, such as the human insulin gene. (You can link this with the Human Genome Project, which has helped us map out all the healthy genes for each protein etc).

    Amplify the gene using the Polymerase Chain Reaction, to produce many copies of the gene.

    Insert the Gene into a Plasmid (circle of DNA commonly found in Bacteria).

    Modify the Bacteria with the plasmids (This step is awkward because the genes won't always take, however a good way of identifying which bacteria have taken up the genes is to also code a gene for antibiotic resistance too and insert that into the plasmid along with the gene for Insulin, then treat the bacteria with Antibiotics, the ones that survive are likely to be the ones who have taken the plasmid, so are the bacteria you want.)

    Place the bacteria in a vat/storage whatever thing you wanna use to allow them to reproduce. They will now begin to produce the protein (drug) you want.

    Advantages include producing large amounts of industrial enzymes cheaply and quickly, also Insulin made from GMOs which have human genes mean that the insulin made will be much more compatible with humans that, say, using Animal Insulin.

    Disadvantages are that there is a risk of the bacteria getting into the general population (this seems to get you a mark, but if we're being realistic, this would never happen because scientist are smart enough to have made these GMOs unable to live outside the lab!), and playing god is ethically questionable!

    Plants:

    Insert therapeutic gene into Bacteria/Virus to be used as a Vector and infect the plant with this vector.

    The pathogen will implant the genetic material into the plants genome for transcription. (Typically, they modify a bacteria which gives plants a type of 'plant cancer' then harvest the tumor cells because they know that these cells carry the gene for the drug).

    Using these harvested cells a new plant is grown (remember how all plant cells are Totipotent and can grow and whole new plant?)

    Now the plant will produce the drug in its fruit etc.

    Advantages being that fruit doesn't require a lot of specialised storage, and (example bananas) can be grown in parts of the world that really need the drug and can be administered without specialist help (eating the Banana gives a dose of the drug, how special!). Also, when we're talking about just modifying plants for other things, you get massive yields and more resistance to predators and such.

    Disadvantages are that some people fear that cross pollination could occur and these genes are spread across wild species which is not likely as most plants that are Genetically modified are also sterile so to prevent this, however making them sterile means they won't reproduce each yeah, thus a new supply has to be bought from the drug company which is expensive! Also, people get all freaky about eat GM crops, god knows why though.

    Animals:

    Genes coding for the desired protein are injected into a fertilised animal egg and this egg is implanted, so that the egg is carried to term and the animal produced has a genome coding for this protein.

    When this animal comes of age, and starts producing milk (for example) the protein will also be produced in the milk, making this milk a source for this drug. Companies can then sell the milk as is (with the drug in it) or purify the drug by separating it from the milk.

    Advantages of modifying animals are that, once you have modified the animal, it can reproduce and you can produce a herd or animals all able to produce the drug.

    Disadvantages is that the products from the animals are very costly typically, which can lead to a two tier system (poor people can't afford so don't get treatment, where rich people can). Also, playing God again, bla bla.

    Hope this helps, this is a heck of a post though.... sorry about that!

    Edit: In my flurry of typing I made some awful spelling mistakes!
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    (Original post by jojo1995)
    thank you guys is this for making sure pressure has no effect on the experiment ? aLso,, what cause the pressure, is it the organoism?
    The pressure difference is just made by the reduction of O2, which is been taken in by the organism. As air decreases, the liquid moves to try to counter act the pressure reduction.

    The control tube is there just to try to make sure that the movement of the liquid is because there is something living in Tube A, rather than just having anything in there.
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    Can someone help me answer these for the pre-release:

    1. Naked mole rats show various adaptations to their particular environment Given an example of these adaptations exhibited by these animals.
    Behavioural adaptation:
    Physiological adaptation:
    Anatomical adaptation:
    2. Give two examples of features that help thermoregulation in most mammals that are reduced or absent in naked mole rats and explain how each operates to help achieve thermoregulation.
    3. Give one advantage and one disadvantage in being poikilothermic in comparison to homeothermy.
    4. The non-reproductive individuals in eusocial animals do not directly transfer their genes to offspring. In spite of this there must still be a genetic advantage in being eusocial – suggest what this must be.
    5. What evidence would scientists look for when searching for evidence of heart disease in naked mole rats?
    6. Suggest how extra molecules attaching to proteins might affect their structure and function.
    7. Suggest what processes would be altered by the cancer causing genes.
    8. Describe the techniques that would be used to insert the cancer causing genes into the cells of the rats.
    9. How might the immune system of immune compromised mice differ from normal mice?
    10. Name the process by which cells replicate (p14) and describe the events that take place in the main events of this process.
    11. Explain how transcription factors bring about expression of a gene (p24)
    12. Describe the procedures of a potential new anti-cancer therapy would have to go through before it could be licensed as a drug.
    13. Explain how impulses would be transmitted from the pain receptors of a rodent to its central nervous system.
    14. What is the sequence of neurones impulses would pass through, to result in withdrawing a hand from a hot stove?
    15. Describe the responses that humans would show if they were breathing air with 5% carbon dioxide, and explain how these responses are brought about.
    16. A brain deprived of oxygen will lead to a brain deprived of ATP/energy. Describe the role of oxygen in the production of ATP.
    17. Explain how populations of naked mole rats have evolved to be resistant to hypoxia.
    18. Use of modern scanning techniques has transformed our understanding of the localisation of function in the brain. Describe how FMRI can be used to study brain function and compare this with early techniques that were used to investigate brain function.
    19. From p47 why are the new prosthetics being developed at UCL less likely to damage tissues, and why is there a problem that must be overcome with these prosthetics.
    20. The queen prevents non-breeders becoming reproductive by altering the hormonal balance in the non breeders. Compare and contrast the ways in which this kind of communication differs from nervous communication.
    21. Describe the techniques and procedures that would be used to produce a DNA fingerprint from a naked mole rat
    22. Suggest why out-breeding is likely to increase the long term survival of the naked mole rat populations.
    23. In the suppression of breeding by the queen identify
    (a) the stimulus
    (b) the effector
    (c) the response for the non-breeding males
    24. From one ethical viewpoint discuss whether some of the experiments carried out on naked mole rats can be justified.
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    (Original post by Mjwilson1988)
    The pressure difference is just made by the reduction of O2, which is been taken in by the organism. As air decreases, the liquid moves to try to counter act the pressure reduction.

    The control tube is there just to try to make sure that the movement of the liquid is because there is something living in Tube A, rather than just having anything in there.
    aww thanks - youre so smart
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    (Original post by Taylor Swift)
    Anyone have a plain copy of the scientific article?
    How's everyone revising for this?? Just reading it or.. ?
    http://www.scribd.com/doc/133218797/...rnational-Only

    Also, revise AS and A2 notes related to topics in the article
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    Anyone can define myogenic please?
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    (Original post by anaab.naeem)
    Can someone help me answer these for the pre-release:

    1. Naked mole rats show various adaptations to their particular environment Given an example of these adaptations exhibited by these animals.
    Behavioural adaptation:
    Physiological adaptation:
    Anatomical adaptation:
    2. Give two examples of features that help thermoregulation in most mammals that are reduced or absent in naked mole rats and explain how each operates to help achieve thermoregulation.
    3. Give one advantage and one disadvantage in being poikilothermic in comparison to homeothermy.
    4. The non-reproductive individuals in eusocial animals do not directly transfer their genes to offspring. In spite of this there must still be a genetic advantage in being eusocial – suggest what this must be.
    5. What evidence would scientists look for when searching for evidence of heart disease in naked mole rats?
    6. Suggest how extra molecules attaching to proteins might affect their structure and function.
    7. Suggest what processes would be altered by the cancer causing genes.
    8. Describe the techniques that would be used to insert the cancer causing genes into the cells of the rats.
    9. How might the immune system of immune compromised mice differ from normal mice?
    10. Name the process by which cells replicate (p14) and describe the events that take place in the main events of this process.
    11. Explain how transcription factors bring about expression of a gene (p24)
    12. Describe the procedures of a potential new anti-cancer therapy would have to go through before it could be licensed as a drug.
    13. Explain how impulses would be transmitted from the pain receptors of a rodent to its central nervous system.
    14. What is the sequence of neurones impulses would pass through, to result in withdrawing a hand from a hot stove?
    15. Describe the responses that humans would show if they were breathing air with 5% carbon dioxide, and explain how these responses are brought about.
    16. A brain deprived of oxygen will lead to a brain deprived of ATP/energy. Describe the role of oxygen in the production of ATP.
    17. Explain how populations of naked mole rats have evolved to be resistant to hypoxia.
    18. Use of modern scanning techniques has transformed our understanding of the localisation of function in the brain. Describe how FMRI can be used to study brain function and compare this with early techniques that were used to investigate brain function.
    19. From p47 why are the new prosthetics being developed at UCL less likely to damage tissues, and why is there a problem that must be overcome with these prosthetics.
    20. The queen prevents non-breeders becoming reproductive by altering the hormonal balance in the non breeders. Compare and contrast the ways in which this kind of communication differs from nervous communication.
    21. Describe the techniques and procedures that would be used to produce a DNA fingerprint from a naked mole rat
    22. Suggest why out-breeding is likely to increase the long term survival of the naked mole rat populations.
    23. In the suppression of breeding by the queen identify
    (a) the stimulus
    (b) the effector
    (c) the response for the non-breeding males
    24. From one ethical viewpoint discuss whether some of the experiments carried out on naked mole rats can be justified.
    wow

    have you got a favorite one I could answer for you ?
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    (Original post by RnTf)
    Anyone can define myogenic please?
    - sets up a wave of depolarisation itself / depolarises itself#
    - a muscle that requires no external stimulus to make it contract
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    (Original post by jojo1995)
    wow

    have you got a favorite one I could answer for you ?
    Any...all... you know whatever you can :P
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    (Original post by Mjwilson1988)
    I'm taking Chem 5 on Wednesday, that one isn't as frightening as Bio 5 though!

    Also, in reply to your question, did you mean the production of Drugs by using GMOs (Plants, Microorganisms and Animals)?

    Microorganisms -

    First isolate a healthy gene which codes for the protein (drug) you wish to make, such as the human insulin gene. (You can link this with the Human Genome Project, which has helped us map out all the healthy genes for each protein etc).

    Amplify the gene using the Polymerase Chain Reaction, to produce many copies of the gene.

    Insert the Gene into a Plasmid (circle of DNA commonly found in Bacteria).

    Modify the Bacteria with the plasmids (This step is awkward because the genes won't always take, however a good way of identifying which bacteria have taken up the genes is to also code a gene for antibiotic resistance too and insert that into the plasmid along with the gene for Insulin, then treat the bacteria with Antibiotics, the ones that survive are likely to be the ones who have taken the plasmid, so are the bacteria you want.)

    Place the bacteria in a vat/storage whatever thing you wanna use to allow them to reproduce. They will now begin to produce the protein (drug) you want.

    Advantages include producing large amounts of industrial enzymes cheaply and quickly, also Insulin made from GMOs which have human genes mean that the insulin made will be much more compatible with humans that, say, using Animal Insulin.

    Disadvantages are that there is a risk of the bacteria getting into the general population (this seems to get you a mark, but if we're being realistic, this would never happen because scientist are smart enough to have made these GMOs unable to live outside the lab!), and playing god is ethically questionable!

    Plants:

    Insert therapeutic gene into Bacteria/Virus to be used as a Vector and infect the plant with this vector.

    The pathogen will implant the genetic material into the plants genome for transcription. (Typically, they modify a bacteria which gives plants a type of 'plant cancer' then harvest the tumor cells because they know that these cells carry the gene for the drug).

    Using these harvested cells a new plant is grown (remember how all plant cells are Totipotent and can grow and whole new plant?)

    Now the plant will produce the drug in its fruit etc.

    Advantages being that fruit doesn't require a lot of specialised storage, and (example bananas) can be grown in parts of the world that really need the drug and can be administered without specialist help (eating the Banana gives a dose of the drug, how special!). Also, when we're talking about just modifying plants for other things, you get massive yields and more resistance to predators and such.

    Disadvantages are that some people fear that cross pollination could occur and these genes are spread across wild species which is not likely as most plants that are Genetically modified are also sterile so to prevent this, however making them sterile means they won't reproduce each yeah, thus a new supply has to be bought from the drug company which is expensive! Also, people get all freaky about eat GM crops, god knows why though.

    Animals:

    Genes coding for the desired protein are injected into a fertilised animal egg and this egg is implanted, so that the egg is carried to term and the animal produced has a genome coding for this protein.

    When this animal comes of age, and starts producing milk (for example) the protein will also be produced in the milk, making this milk a source for this drug. Companies can then sell the milk as is (with the drug in it) or purify the drug by separating it from the milk.

    Advantages of modifying animals are that, once you have modified the animal, it can reproduce and you can produce a herd or animals all able to produce the drug.

    Disadvantages is that the products from the animals are very costly typically, which can lead to a two tier system (poor people can't afford so don't get treatment, where rich people can). Also, playing God again, bla bla.

    Hope this helps, this is a heck of a post though.... sorry about that!

    Edit: In my flurry of typing I made some awful spelling mistakes!
    Oops yeah i meant the production of drugs by using GMOs. Sorry my mistake Thank you sooo much for this!! Great explanation :") I understand better now

    i'm giving you a rep tomorrow cause i can't rate anyone now. You're bound to get an A*
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    Could someone please define oxidative stress?
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    (Original post by anaab.naeem)
    Any...all... you know whatever you can :P
    1. Naked mole rats show various adaptations to their particular environment Given an example of these adaptations exhibited by these animals.
    Behavioural adaptation: soldiers stay and fight rather than run away ???? not sure about this one ... if anyone can confirm ?
    Physiological adaptation: resistance to hypoxia ...to deal with their low oxygen envrionment
    Anatomical adaptation: huge yellow teeth for digging
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    (Original post by anaab.naeem)
    Any...all... you know whatever you can :P
    Man, I started answering the questions but the amount of time it's going to take! Especially since you've not given reference to the text where you're getting the questions from, which makes it a lot more difficult!

    Here is what I've got for the first couple of questions:

    1a) Behavioral, they work in colonies, rather than as single organisms, each with their own job, so workers work and soldiers defend despite it being risky.
    1b) Physiological - Resistant to cancer, they are able to live in highly concentrated CO2 environments (so more acidic). Resistant Enzymes etc.
    1c) Anatomical - Massive teeth to help dig, Lack of eyesight as it is dark, no fur as it is warm down there.

    2) Lack of sweat glands - Sweat evaoporates off the skin so heat is lost by evaporation.
    Lack of fur - fur typically insults, is controlled by errector pili muscles and traps air, increasing insulation.
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    (Original post by Mjwilson1988)
    Man, I started answering the questions but the amount of time it's going to take! Especially since you've not given reference to the text where you're getting the questions from, which makes it a lot more difficult!

    Here is what I've got for the first couple of questions:

    1a) Behavioral, they work in colonies, rather than as single organisms, each with their own job, so workers work and soldiers defend despite it being risky.
    1b) Physiological - Resistant to cancer, they are able to live in highly concentrated CO2 environments (so more acidic). Resistant Enzymes etc.
    1c) Anatomical - Massive teeth to help dig, Lack of eyesight as it is dark, no fur as it is warm down there.

    2) Lack of sweat glands - Sweat evaoporates off the skin so heat is lost by evaporation.
    Lack of fur - fur typically insults, is controlled by errector pili muscles and traps air, increasing insulation.
    Thanks for doing the first 2 I kind of suck at Biology (I only took it because my dad made me) and I literally can't do anything.
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    (Original post by nukethemaly)
    Could someone please define oxidative stress?
    This might be a little out of the realm of the spec I think but here is what I know:

    Oxidative stress is when cells have a build up of Oxygen Free Radicals (Those nasty little things with free, unpaired, electrons that just go about f*****g stuff up for everyone else by causing damage). These free radicals are produced by respiration and other metabolic processes and they are related to the effects of aging (as they cause damage to skin cells and their DNA), Cancers (again, messing with DNA) and loads of other bad diseases.

    Pretty much, this is the stress placed on cells by oxygen free radicals, and occurs when the amount of Oxygen free radicals being produced outweighs the amount of Antioxidants (the things that combat the radicals), produced.
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    (Original post by nukethemaly)
    Could someone please define oxidative stress?
    free radicals attach to proteins, lipids, and other structures in a cell, causing damage
 
 
 
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