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  1. D

    BIO Doubts..here..everyone!!

    Ecology isn't hard, it's just really long. First there's food chains and webs, you gotta know things like producers and primary/secondary consumers. Then there're pyramids of biomass/energy, I never really focused on those, they don't come in exams alot. There's also water/nitrogen/carbon...
  2. D

    BIO Doubts..here..everyone!!

    http://en.wikipedia.org/wiki/Zona_pellucida Seems like some pretty in-detail stuff about fertilization. You sure we have to learn that? Well it's not in my book xD And yep, LH causes ovulation which is bursting of Graafian Folicle to release ovum into oviduct, and what remains after follicle...
  3. D

    BIO Doubts..here..everyone!!

    Yep what I meant was that it forms after bursting, but only keeps secreting progesterone if the egg was fertilized. Otherwise it's broken down.
  4. D

    BIO Doubts..here..everyone!!

    Progesterone is also made by the placenta during pregnancy, and by the corpus luteum (remains of follicle after bursting) if the egg was fertilized. [And damn I wanna get the sandwich in your avatar xD]
  5. D

    BIO Doubts..here..everyone!!

    It's a study-notes book made by my teacher, using information mainly from the official book too and from another book (can't remember the name), but don't start saying it could be wrong, I've never found any mistakes in it. Probably one of us just seems to mis-understand something..
  6. D

    BIO Doubts..here..everyone!!

    In my book it says that FSH itself develops the Graafian Follicle in the ovary till it bursts during ovulation and releases egg in oviduct. Oestrogen just repairs the uterus lining after ovulation and stimulates LH production.
  7. D

    BIO Doubts..here..everyone!!

    Actually yea I got confused, Oestrogen doesn't stimulate FSH, it stimulates LH, which is Luteinizing Hormone that causes ovulation. Now I think having oestrogen in contraceptive pills doesn't matter, since even it stimulates LH, ovulation wont occur since there're no produced eggs(no FSH due to...
  8. D

    BIO Doubts..here..everyone!!

    But Oestrogen is produced by Graafian follicles without pregnancy anyway, actually is it even produced during pregnancy?. I know progesterone stops FSH (which develops more eggs) and LH (which causes ovulation). But the presence of oestrogen too seems to cancel what progesterone does(since it...
  9. D

    BIO Doubts..here..everyone!!

    Uhm there's something confusing in contraceptive pills. It says they contain progesterone which stops secretion of LH by negative feedback mechanism, and also contains oestrogen. But doesn't oestrogen actually stimulate LH secretion?
  10. D

    BIO Doubts..here..everyone!!

    Meiosis: 1- Happens in reproductive organs (gonads [testis, ovaries, anther]) to produce gametes (haploid - half number of chromosomes, 23 in humans) 2- Causes variation due to crossing over of non-sister chromatids and independent assortment of chromosomes. Mitosis: 1-Happens in all cells for...
  11. D

    biology p61

    What do you mean by 'resetting'? And all I want is a reason why people think that bar charts are wrong. Many people here AND in my school are saying that, but none of them can give a reason. I just don't believe in saying that something 'is WRONG' just because 'it's like that' or 'it's just...
  12. D

    biology p61

    Oh I guess you finally realise that you're wrong and got nothing else to say? Good.
  13. D

    biology p61

    Agree with him about? Elaborate.
  14. D

    biology p61

    1- You ARE wrong, unless you can prove otherwise. You still haven't given us a reason why you think bar chart is wrong, but rather trying to change the subject, remember? 2-'Are you a person who just argue's about studying?' Huh..what the hell does that mean? 3-'Just go away' Hmm apparently your...
  15. D

    biology p61

    If anyone actually notices, all those who say it' s line and not bar can't even bother to say why, or give any reason whatsoever. I bet deep inside they know it's wrong, but they're just lying to themselves in hope that what they're saying will be true, since it's too late to change things. But...
  16. D

    biology p61

    1- 'It's not correct variation'? What the hell is that supposed to mean? Variation : A change or slight difference in condition, amount, or level, typically with certain limits. The areas were different in amount (number) at different time intervals, and there you go...THATS VARIATION. I don't...
  17. D

    biology p61

    My teacher already confirmed it's a bar chart. So how about you enlighten us with the reason why you THINK it's a line and not a bar, instead of repeating 'it's not a bar' over and over?
  18. D

    ADVICE

    Oh okay. Thanks alot for your encouragement :D I was wondering which subject(s) do you teach? Since I'm having some doubts in some of them..
  19. D

    ADVICE

    So according to June 2010 Grade threshold Biology paper 31 had A at 37/80 and C at 25. That means B was at (37+25)/2 = 31 Then difference is 37-31=6 And that means A* is at 37+6= 43/80 in P3? That seems so damn easy to get xD I calculated it right didn't I? ;p
  20. D

    ADVICE

    Got any advice on how to study biology paper 3 and how to practice for it? Also, do you have an idea of what's the average required mark for an A* in biology over the past years? Would be greatly appreciated if you could enlighten us ^^
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