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    (Original post by justanotherindigo)
    -Cellulose microfibrils are made up of 50-80 cellulose molecules
    -A cellulose molecule is composed on beta-glucose, 1-4 glycosidic bonds and are unbranched. Hydrogen bonds occur in adjacent OH groups...

    -Microfibrils have a net-like structure
    -This arrangement ensures that plant fibres are both strong and rigid

    Yh thanks it does
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    (Original post by maryam1996)
    Both Pits and Plasmodesmata are involved in cell-to-cell transport but the difference is that in plasmodesmata both cell walls are absent (Primary and secondary cell wall) but the pit only has a secondary cell wall absent ( but primary cell wall is still present) Hope this helps
    hi where does it say this?

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    William Withering added different concentrations of digitalis to foxgloves, so did the digitalis act as something to dilute the foxgloves so it was less powerful
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    could someone please explain genetic diversity to me and also are phenotypes the result of genotypes and environment?
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    Anyone got a prediction for which core practical may come up?

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    (Original post by Randy123)
    could someone please explain genetic diversity to me and also are phenotypes the result of genotypes and environment?
    I can answer one of your questions! Genetic diversity refers to the allele frequency in a gene pool


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    (Original post by Randy123)
    could someone please explain genetic diversity to me and also are phenotypes the result of genotypes and environment?
    1. Genetic diversity is the number of alleles in a gene pool.
    2. Correct
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    (Original post by Lucy96)
    Anyone got a prediction for which core practical may come up?

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    it ll not be mineral ions...
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    Is the only difference between the primary cell wall and secondary cell wall that the secondary cell wall is lignified?

    (This reads so badly but I can't think of a better way to phrase it.)
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    (Original post by calm down)
    1. Genetic diversity is the number of alleles in a gene pool.
    2. Correct
    and a gene pool is all the alleles present in all the genes in a population
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    (Original post by Randy123)
    and a gene pool is all the alleles present in all the genes in a population
    (Original post by Chocip)
    Is the only difference between the primary cell wall and secondary cell wall that the secondary cell wall is lignified?

    (This reads so badly but I can't think of a better way to phrase it.)
    Correct, +1 to each. However to Chocip, The secondary cell wall is thicker than the primary cell wall.
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    anyone have a good definition for genotype and phenotype?
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    (Original post by Randy123)
    anyone have a good definition for genotype and phenotype?
    Genotype = the alleles a person has eg BB, Bb, or bb for eye colour

    Phenotype = the characteristics that the alleles produce eg brown eyes


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    (Original post by CoolRunner)
    Correct, +1 to each. However to Chocip, The secondary cell wall is thicker than the primary cell wall.
    so what is the difference between a gene pool and genetic diversity?
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    (Original post by Randy123)
    anyone have a good definition for genotype and phenotype?
    Genotype: It is the genetic make up of a living being. It posses a particular set of genes gained from the parents.

    Phenotype: are the traits that are physically expressed. i.e the traits are visible. Examples: Eye colour, hair colour, etc.
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    (Original post by Randy123)
    so what is the difference between a gene pool and genetic diversity?
    Isn't a gene pool the alleles that someone has? And genetic diversity is HOW diverse the alleles are in a gene pool?


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    (Original post by Randy123)
    so what is the difference between a gene pool and genetic diversity?
    The gene pool is the complete set of alleles in a species.

    Genetic diversity however, is the variation of alleles within a species.

    I hope this helps.
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    (Original post by CoolRunner)
    Genotype: It is the genetic make up of a living being. It posses a particular set of genes gained from the parents.

    Phenotype: are the traits that are physically expressed. i.e the traits are visible. Examples: Eye colour, hair colour, etc.
    core practical u expect to come? i thnk it's either for observing mitosis or totipotency! do u agree?
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    (Original post by CoolRunner)
    The gene pool is the complete set of alleles in a species.

    Genetic diversity however, is the variation of alleles within a species.

    I hope this helps.
    so if i was to define genetic diversity i would say the number of variations of alleles present in a gene pool?
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    (Original post by maryam1996)
    Both Pits and Plasmodesmata are involved in cell-to-cell transport but the difference is that in plasmodesmata both cell walls are absent (Primary and secondary cell wall) but the pit only has a secondary cell wall absent ( but primary cell wall is still present) Hope this helps
    oh okay! so pits are like REDUCED cell walls whereas with plasmodesmata there are no cell walls at all? thanks!!!
 
 
 
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