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Meiosis Watch

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    I know that meiosis produces gametes which each have 23 chromosomes but if meiosis produces 4 haploid cells which are the gametes or do they make 2 copies of gametes? So if one is a sperm cell and the other is an egg cell and what are the other two for?
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    So the egg and the sperm fuse during fertilisation. So you've got one cell with 2 pairs now, then the pairs double, and then half to produce two copies of the cell that is a fuse of sperm and egg
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    (Original post by Daydreamer3)
    I know that meiosis produces gametes which each have 23 chromosomes but if meiosis produces 4 haploid cells which are the gametes or do they make 2 copies of gametes? So if one is a sperm cell and the other is an egg cell and are the other two for?
    all 4 are gametes

    all 4 are either sperm or all 4 are either eggs (ova) depending on whether it was a male or female body that produced them

    in terms of "copies" all 4 are genetically different.

    hope that helped
    Spoiler:
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    remember sperm is produced all the time so meiosis happens alot over and over again


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    (Original post by alkaline.)
    all 4 are gametes

    all 4 are either sperm or all 4 are either eggs depending on whether it was a male or female body that produced them

    Spoiler:
    Show


    remember sperm is produced all the time so meiosis happens alot over and over again

    But why would you need 4 sperms and egg? Is it because our body is made up of loads of sperm and eggs and only when fertilised an egg and sperm from a male and a female join. But there is still loads of sperm and egg left in the male and female?
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    (Original post by That'sGreat)
    So the egg and the sperm fuse during fertilisation. So you've got one cell with 2 pairs now, then the pairs double, and then half to produce two copies of the cell that is a fuse of sperm and egg
    That's confusing....
    So an egg and sperm each have 23 chromosomes so when they fertillise the cell has 46 chromosomes, 23 from each. Why would the pairs double and half because meiosis occurs to produce the egg and sperm cell so it cant happen after fertilisation??....
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    (Original post by alkaline.)
    all 4 are gametes

    all 4 are either sperm or all 4 are either eggs (ova) depending on whether it was a male or female body that produced them

    in terms of "copies" all 4 are genetically different.

    hope that helped
    Spoiler:
    Show




    remember sperm is produced all the time so meiosis happens alot over and over again



    How are all 4 cells produced genetically different? Is it because when the chromosomes were pairing up, each chromosome paired with a different one?
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    (Original post by Daydreamer3)
    But why would you need 4 sperms and egg? Is it because our body is made up of loads of sperm and eggs and only when fertilised an egg and sperm from a male and a female join. But there is still loads of sperm and egg left in the male and female?
    you have way more than 4:
    I think women have around 300 000 eggs at puberty and men produce sperm everyday so god knows how many they have (millions).

    Our body isn't made up of gametes, haploid cells only exists in our sex organs because their purpose is reproduction.
    The rest of your body as it stands is diploid, all your other cells have full sets of chromosomes.

    I don't really understand what you mean by the part in bold, could you please clarify?
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    (Original post by alkaline.)
    you have way more than 4:
    I think women have around 300 000 eggs at puberty and men produce sperm everyday so god knows how many they have (millions).

    Our body isn't made up of gametes, haploid cells only exists in our sex organs because their purpose is reproduction.
    The rest of your body as it stands is diploid, all your other cells have full sets of chromosomes.

    I don't really understand what you mean by the part in bold, could you please clarify?
    Ohh right I understand now and the part in bold is what you already explained about women have 300,000 eggs and so on.

    So when does meiosis take place?
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    (Original post by Daydreamer3)
    Ohh right I understand now and the part in bold is what you already explained about women have 300,000 eggs and so on.

    So when does meiosis take place?
    In females it starts when they are in the womb. When a female is born it doesn't happen, she is born with all the eggs she'll ever have.
    In males, meiosis only occurs after/at puberty and from there it happens constantly.
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    (Original post by alkaline.)
    In females it starts when they are in the womb.
    In males, meiosis only occurs after/at puberty and from there it happens constantly.
    Ohh okay thank you!!

    Do you know when and where mitosis occurs when it is needed for growth? So what is it actually growing?
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    (Original post by Daydreamer3)
    Ohh okay thank you!!

    Do you know when and where mitosis occurs when it is needed for growth? So what is it actually growing?
    you can google these questions for better answers lol

    From what I know, it occurs all over the body wherever cells are needed so skin, heart, stomach cells etc. Skin cells only have a lifespan of a couple of weeks.

    What is actually growing? Imagine a cell as a slice of play dough. If you keep adding slices of play dough the mass will grow right? So when certain cells die or are damaged then your body makes new ones to replace them

    Remember mitosis happens in the nucleus so cells that don't have a nucleus won't replace themselves by mitosis for example red blood cells.

    Mitosis is also involved in the growth of an embryo.
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    (Original post by alkaline.)
    you can google these questions for better answers lol

    From what I know, it occurs all over the body wherever cells are needed so skin, heart, stomach cells etc. Skin cells only have a lifespan of a couple of weeks.

    What is actually growing? Imagine a cell as a slice of play dough. If you keep adding slices of play dough the mass will grow right? So when certain cells die or are damaged then your body makes new ones to replace them

    Remember mitosis happens in the nucleus so cells that don't have a nucleus won't replace themselves by mitosis for example red blood cells.

    Mitosis is also involved in the growth of an embryo.
    Aha its only when google hasn't been able to give me what I need, I come to TSR.
    Can you please explain how mitosis is involved in the growth of an embryo because that is what am confused about. I read that "The new cell then divides over and over again by mitosis" but why does it divide? Is it to produce all the cells in our body to eventually form an individual?
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    (Original post by Daydreamer3)
    Aha its only when google hasn't been able to give me what I need, I come to TSR.
    Can you please explain how mitosis is involved in the growth of an embryo because that is what am confused about. I read that "The new cell then divides over and over again by mitosis" but why does it divide? Is it to produce all the cells in our body to eventually form an individual?
    it's not only mitosis, extracellular material is used to make the embryo as well. Yes you're right, it divides to eventually make an individual, remember the play dough thing I said, a whole human isn't just one cell:

    Remember by definition, layers of cell make up tissues and tissues make up our organs. Therefore cells divide by mitosis so they are genetically identical but then they specialise into stomach cells skin cells etc.
    This is also why every nucleus in your body actually has the genetic information to be any other cell despite being specialised for it's own environment.

    I can't really get into how they specialise/differentiate more without getting to A level Standard biology.

    This might help http://www.pregnancy-baby-care.com/a...velopment.html
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    (Original post by alkaline.)
    it's not only mitosis, extracellular material is used to make the embryo as well. Yes you're right, it divides to eventually make an individual, remember the play dough thing I said, a whole human isn't just one cell:

    Remember by definition, layers of cell make up tissues and tissues make up our organs. Therefore cells divide by mitosis so they are genetically identical but then they specialise into stomach cells skin cells etc.
    This is also why every nucleus in your body actually has the genetic information to be any other cell despite being specialised for it's own environment.

    I can't really get into how they specialise/differentiate more without getting to A level Standard biology.

    This might help http://www.pregnancy-baby-care.com/a...velopment.html
    Thank you very much!
 
 
 
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