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    what is the equivalent legacy unit called for ocr biology from the old spec, wanted to do some past papers but not sure what im looking for tbh. thanks in advance
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    When lactose is not present in the solution, a regulator gene is expressed and a repressor protein is formed. this binds to either lactose or the operator, obviously because lactose is absent the repressor protein can only bind to the operator, if this happens this blocks the RNA polymerase from binding to the promotor which is next to the operator. so structural genes (such as in this case beta glactosidase and lactose permease cannot be formed) and when lactose is present then the represser protein binds with lactose substrate, which changes the shape of the represser protein so that it can no longer bind with the operator hence not inhibiting the RNA polymerase binding with the promotor allowing the structural genes to be made
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    (Original post by MadMaths)
    When lactose is not present in the solution, a regulator gene is expressed and a repressor protein is formed. this binds to either lactose or the operator, obviously because lactose is absent the repressor protein can only bind to the operator, if this happens this blocks the RNA polymerase from binding to the promotor which is next to the operator. so structural genes (such as in this case beta glactosidase and lactose permease cannot be formed) and when lactose is present then the represser protein binds with lactose substrate, which changes the shape of the represser protein so that it can no longer bind with the operator hence not inhibiting the RNA polymerase binding with the promotor allowing the structural genes to be made
    Hey nice to see you again.Oh which chapter is this?
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    (Original post by ibysaiyan)
    Hey nice to see you again.Oh which chapter is this?
    Nice to see you too
    depending on which book you use: (ocr endorced) unit 2 module 1, page 113
    or
    mary jones biology 2: chapter 7 celluar control, page 101
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    (Original post by MadMaths)
    Nice to see you too
    depending on which book you use: (ocr endorced) unit 2 module 1, page 113
    or
    mary jones biology 2: chapter 7 celluar control, page 101
    Ah k oh yea ! lac operon T.T
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    (Original post by ibysaiyan)
    Ah k oh yea ! lac operon T.T
    what chapter you up to???....i need a lot of catching up to do...havnt looked at a book since jan exams....im just up to biotech
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    I'm revising biology too atm, just reviewing some of the module one stuff, seems like so long ago :/
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    (Original post by CreativeBass)
    I'm revising biology too atm, just reviewing some of the module one stuff, seems like so long ago :/
    Could you please summarise for me meiosis(an outline nothing detailed) ?
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    (Original post by MadMaths)
    what chapter you up to???....i need a lot of catching up to do...havnt looked at a book since jan exams....im just up to biotech
    almost done with chapter 11 will soon drift through 12. Mama jones aka Mary Jones.
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    (Original post by Remarqable M)
    Could you please summarise for me meiosis(an outline nothing detailed) ?
    Okay, meiosis is split into two parts:
    during prophase I - telophase I; chromsomes come together in homologous pairs forming a bivalent. non sister chromatids wrap around each other and attach at chiasmata. crossing over takes place which leads to genetic variation. the bivalents line up across equator of spindle, attach at the centromeres and random assortment of chromosomes takes place...furhter genetic variation. then they are pulled to opposite poles and chiasmata seperate. nuclear envelolpe forms around each set of chromosomes.
    prophase II - Telophase II: nuclear envelope breaks down and spindles form, chromosome condense. they arrange at the equator and chromatids are randomly assorted..more genetic variation. then centromeres divide andchromatids pulled to opposite poles and segregate. nuclear envelope forms around the haploids.

    sorry if its not a good summary, i hate meiosis and just learnt it by basically memorising it from the book, so if it seems crappy then im sorry
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    omg LOL MY COURSEWORK MARK IS TERRIBLE
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    (Original post by Ziffachan)
    omg LOL MY COURSEWORK MARK IS TERRIBLE
    What did you get ? Mines 23 that's ridiculous.
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    (Original post by ibysaiyan)
    almost done with chapter 11 will soon drift through 12. Mama jones aka Mary Jones.
    woowzaa...way ahead....ahh mama jones..lol...just for the record guys haemophilia can occur in women if the mother is the carrier and father has it.....why is it rare in women??? i think its cause that there would be no father alive with heamophilia...does anyone know a more detailed reason?...im not sure my reason is right:confused:
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    (Original post by uer23)
    What did you get ? Mines 23 that's ridiculous.
    Mine wasn't quite that bad haha, 29

    I can still get an A*

    But some little **** neg repped me saying "try harder". Try not being a little coward? Idiot.
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    (Original post by Ziffachan)
    Mine wasn't quite that bad haha, 29

    I can still get an A*

    But some little **** neg repped me saying "try harder". Try not being a little coward? Idiot.
    :lol: in this thread? or somewhere else?
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    (Original post by MadMaths)
    woowzaa...way ahead....ahh mama jones..lol...just for the record guys haemophilia can occur in women if the mother is the carrier and father has it.....why is it rare in women??? i think its cause that there would be no father alive with heamophilia...does anyone know a more detailed reason?...im not sure my reason is right:confused:
    Alright as far as i can recall the reason behind it is because its sex-linked disease and so as a result you dont get X^hX^h the fetus doesn't survive so in a womans case she is a carrier but for males .
    Ok i haven't looked into the book myself i hope someone clarifies on this.
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    (Original post by Ziffachan)
    Mine wasn't quite that bad haha, 29

    I can still get an A*

    But some little **** neg repped me saying "try harder". Try not being a little coward? Idiot.
    Hahah lol.
    yep all you need to get is 1005 in f215 and 100% in f214.
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    Use of genetic engineering:
    Golden Rice.
    Vitaimin A or Retinol is important part of a balanced diet.It synthesizes rodophsin which stimulates the working of rod cells in the retina lack of this causes Color blindness.It is present in great quantity in meats especially liver.People depending on rice or vegetarians can overcome this by eating carrots, which cant be widely available.To overcome this a new breed of GM rice is made.These have greater quantity of B-carotene makes Vit.A.

    Xeno-Transplantationuppose if someones vital organ such as liver,kidney or heart is damaged and not capable enough it can be replaced by transplanting animal organ but here is where human immune response kicks in. human antibodies attach to the pig cells receptor (glycoprotein) only if a particular sugar is present. This sugar is made by enzyme GGTA1 so to overcome refusal scientists have located this gene and removed it off the pigs genome.Again this whole process has flaws within it.Some are ethical/religious based other alot more complex.
    Few complex ones to be noted are:
    1) what if a virus from pig enters the host body?2)yet a risk of rejection as there might be more receptors complementary to the antibodies.3)The organ doesn't survive for much long. 4)Would customizing (lol) pigs organ make it less efficient by any means?

    -----------------------------------------------------------------
    Genetic Therapy(GT): Treatment of a disease by changing the genes of an organism.


    GT is used in to treat CF and SCID (Severe Combined immunodeficiency disease).

    CF: Is a recessive linked disease caused by the fauly genes in chromosome 9.It is caused by deletion of 3 bases (one codon hence one amino acid) in the allele.In a normal person this "normal" CFTR allele codes for a transporter chain:p: (which is also CFTR wanna know the full name?lol Cystic fibrosis transmembrane conductance regulator) which is found around the lung pathway and around the alveoli.Under normal conditions CFTR removes Cl ions to the outside of the cell hence a water potential gradient forms from in to the outiside(Reminds me of Loop of henle and Distal convoluted tubule lol curses ocr).This makes the mucus more thin.So that cilia could easily waft it through.
    Since CF is a recessive disease so there is a greater chance of curing a carrier person as only one alleles need to be replaced.However practically it hasn't given out much piece of sweetness.
    Liposomes (balls of lipid with DNA) had these "normal" genes inserted into them ,these were then sprayed as a nasal spray the idea was to get them through the lipid membrane and replace faulty ones.It was successful but the cell lifetime was pretty short on another hand viruses were injected which caused side effects to some recipients.
    -----------------------------------------------------------------
    Somatic Gene therapy: Is treatment in which a non-reproducing cell is treated such that the person is cured but his offspring would still carry.
    Germ Line therapy: Is where sex cells are treated which later become gametes to a possible zygote.




    End of SHAPTER 11.
    Things to make a note of: Names!!! yep thats it make sure you know what goes where.... let me post few down.
    Genome: Sets of all the genes in an organism or a population of organisms.
    Genetic Engineering: Use of technology to change the genetic material of an organism.
    Electrophoresis (GRRRR like 70% of the time i get confused whether to say electrophoreosis or electrophoresis the way i overcome it by imaging the 'pho' bit to a photon lol): Method of sequencing down a genome.

    Then comes the words starting with 'P'! yep grrr XDxDX
    Primer:20 base pair long initaites PCR
    Promoter:Place in lac operon where rna polymerase sits.(ch:7)
    Probe: 100 b.p long which detect start of a particular gene.
    Restriction Enzymes: Enzymes which cut through dna in a stick way (lol).
    Reverse Transcriptase:mrna to DNA enzymes.
    Annealing: Process where primers + Dna occurs.
    PCR:Temperatures to be noted:
    1) Denatuing dba and breaking it into 2 strands requires: 95C
    2)annealing : 65C
    3)Dna Polymerization:72C

    END OF SHAPTER 11/ I hope all this stays fit within my synapses ................................ ................................ ................................ ................................ .......................
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    (Original post by ibysaiyan)
    Hahah lol.
    yep all you need to get is 1005 in f215 and 100% in f214.
    1005? I worked it out as about 135 lol...

    But yeah I think 135/150 is just about achievable
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    (Original post by Remarqable M)
    :lol: in this thread? or somewhere else?
    Yep haha, in here on my post where I said my coursework mark is awful

    Little *******
 
 
 
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